CN106640004A - Calculating method and device of steam thermal parameter of steam-injection boiler outlet - Google Patents

Abstract

The invention discloses a calculating method and device of a steam thermal parameter of a ground gas conveying pipeline boiler outlet. The calculating method comprises the steps that calculation parameters are obtained, and the calculation parameters comprise the temperature and dryness fraction of steam at a steam-injection wellhead, a ground pipeline parameter and a ground pipeline external environment parameter; according to the calculation parameters, the heat loss amount of the steam from the steam-injection boiler outlet to the steam-injection wellhead is calculated iteratively; and under the condition of ignoring the change of the pressure and the gravity in a ground pipeline, an energy control equation is built according to the energy balance law, and the dryness fraction of the steam of the steam-injection boiler outlet is determined.

Description

The computational methods and its device of the steam thermal parameter of outlet of steam boiler

Technical field

The present invention relates to the field of heavy oil thermal recovery in field of petroleum exploitation, more particularly to a kind of steam injection of ground gas transmission line The computational methods and its device of the steam thermal parameter of boiler export.

Background technology

Viscous crude refers to that viscosity is more than 50mps (mpas), or degassed crude viscosity under reservoir temperature under formation condition For the high viscosity heavy crude of 1000 to 10000mps.Because viscosity of thickened oil is big, therefore mobile performance is poor, or even at some Can not flow under reservoir condition, to the exploitation of viscous crude difficulty is brought.In the oil exploitation in oil field, due to viscous crude have it is special High viscosity and high-solidification point characteristic, the poor fluidity in reservoir and pit shaft, conventional exploitation recovery ratio is low, i.e., cannot ensure just Normal economic flow rate.In order to ensure rational recovery ratio, recover the oil often through the viscosity for reducing crude oil.

Steam injection heating exploitation viscous crude technology can reduce Viscosity of Heavy Crude Oil, improve mobility ratio, reduce residual oil saturation, carry High oil displacement efficiency.High temperature and high pressure steam used by steam injection heating exploitation viscous crude technology is produced in steam injection station, is then passed through Surface line is delivered to well head, then injects stratum by pit shaft by well head.Unavoidably there is heat in migration process in steam Loss, in order to ensure that reaching shaft bottom steam retains higher mass dryness fraction, reaches preferable steam injection efficiency, outlet of steam boiler steam heat The design of force parameter is most important.

Existing method is to calculate well head steam parameter by starting point of outlet of steam boiler, and then calculates steam arrival shaft bottom When thermodynamic parameter, the invention provides the pressure, temperature, mass dryness fraction and steam injection speed needed for a kind of known well head steam, in advance Calculation realizes under the conditions of the well head steam parameter that boiler export steam needs pressure, temperature, the mass dryness fraction for reaching, and calculates in steam injection During whole surface line steam parameter change, provide reliable basis for the design of Boiler Steam injection parameter.

The content of the invention

It is an object of the invention to provide a kind of calculating of the steam thermal parameter of the outlet of steam boiler of ground gas transmission line Method and its device, can determine the steam thermal parameter of outlet of steam boiler, so as to design for Boiler Steam injection parameter Reliable basis are provided.

To reach above-mentioned purpose, the present invention provides a kind of computational methods of the steam thermal parameter of outlet of steam boiler, bag Include：

Calculating parameter is obtained, the calculating parameter includes：Steam injection well head steam pressure, temperature, mass dryness fraction, surface line ginseng Number, surface line external environment parameter；

According to the calculating parameter, the heat loss amount of outlet of steam boiler to steam injection well head steam is iterated to calculate；

Ignore and energy hole equation is set up according to energy balance law under conditions of pressure in surface line, Gravity changer, Determine the mass dryness fraction of steam at surface line outlet of steam boiler.

As one kind preferred embodiment, the heat loss amount's bag for calculating outlet of steam boiler to steam injection well head steam Include：

Set the default heat insulation layer hull-skin temperature on the pipeline；

The pipeline entire thermal resistance is calculated by the default heat insulation layer hull-skin temperature, is calculated by the pipeline entire thermal resistance Pipeline gas transmission is along journey heat loss；Heat insulation layer hull-skin temperature is calculated along journey heat loss according to the pipeline gas transmission；

Iterate, when the heat insulation layer hull-skin temperature calculated value and setting value meet the first predetermined accuracy, it is determined that The pipeline insulation layer hull-skin temperature, to obtain the heat loss of outlet of steam boiler to steam injection well head steam.

As one kind preferred embodiment, using the heat waste in following computing formula unit of account length surface line Lose：

In above formula, q be the unit time in, in unit length surface line in heat loss, unit kilocalorie/(hour Rice)；T_sFor vapor (steam) temperature, degrees Celsius；T_aFor environment temperature, degrees Celsius；R is total in unit length surface line Thermal resistance value, unit (meters per hour degree Celsius)/kilocalorie；

By the product of the heat loss in the numerical value of the material calculation and the unit length surface line, it is determined that described Heat loss in surface line.

As one kind preferred embodiment, the calculating surface line entire thermal resistance includes：

Entire thermal resistance R of surface line, is calculated according to following formula：

In above formula, R be surface line thermal resistance value, R₁For steam in surface line and the thermal resistance of liquid film layer heat convection Value, R₂For steam in surface line and the thermal resistance value of schmutzband heat convection, R₃For the thermal resistance value of the heat transfer of tube wall, R₄For exhausted The thermal resistance value of thermosphere heat transfer, R₅For thermal resistance value of the surface line to the forced-convection heat transfer of air, unit is that (rice is little When degree Celsius)/kilocalorie；h_fFor liquid film layer convection transfer rate, h_pFor schmutzband convection transfer rate, h_fcFor heat insulation layer appearance The hot coefficient of forced convection on face, unit is kilocalorie/(square meters per hour degree Celsius)；λ_pFor the heat conduction system of surface line Number, kilocalorie/(meters per hour degree Celsius)；r_iFor surface line inside radius, r_oFor surface line outer radius, r_insOutside for heat insulation layer Radius, unit is rice；

Wherein, surface line includes the heat convection and pipe of heat insulation layer outer surface to air to the forced-convection heat transfer of air The radiation heat transfer of outer wall to air；

The convection transfer rate h of the heat insulation layer outer surface to air_fc', its computing formula is as follows：

In above formula, λ_aFor the thermal conductivity factor of air, unit kilocalorie/(meters per hour degree Celsius)；Re is Reynolds number, is passed through Following formula is calculated：

Re=ν_aD_s/υ_a

In above formula, ν_aFor wind speed, unit meter per second；υ_aFor the kinematic viscosity of air, unit square meter per second；D_sFor heat insulation layer External diameter, unit rice；Wherein C, n are chosen according to Re according to pre-defined rule；

The radiation heat transfer coefficient h of pipe outer wall to air_fc", its computing formula is as follows：

In above formula, ε is the outer blackness of tube wall, nondimensional number；T_aFor average temperature of air, degrees Celsius；T_wOutside for heat insulation layer Wall temperature, degrees Celsius.

As one kind preferred embodiment, heat insulation layer hull-skin temperature is calculated using following computing formula：

In above formula, h_fFor liquid film layer convection transfer rate, h_pFor schmutzband convection transfer rate, λ_pLeading for surface line Hot coefficient, kilocalorie/(meters per hour degree Celsius)；r_iFor surface line inside radius, r_oFor surface line outer radius, r_insFor thermal insulation Layer outer radius, unit is rice；Q be the unit time in, in unit length surface line in heat loss, unit kilocalorie/(little When rice)；T_sFor vapor (steam) temperature, degrees Celsius；T_wFor heat insulation layer outside wall temperature, degrees Celsius.

As one kind preferred embodiment, it is described to be included according to energy balance law calculating mass dryness fraction step：

Set up following energy hole equation：

By steam injection well head steam quality x |_Z=L=x_uAs primary condition, above-mentioned equation is solved, obtain outlet of steam boiler Steam quality calculation expression formula

So as to the steam quality of boiler export calculates formula and is：

In above formula, q be unit chronomere length surface line in steam heat loss, unit kilocalorie/(hour rice)； Z is the distance for calculating position and boiler export, unit rice；G be saturated vapor mass flow, unit kg/hr；L_vFor vaporization Latent heat, kcal/kg；x_uFor steam injection well head (surface line end) steam quality, dimensionless；

Above-mentioned latent heat of vaporization L_vThe difference of the heat content of heat content and saturation water for dry saturated steam, its computing formula is：

L_v=273 × (374.15-T)^0.38=h_g-h_l；

h_lFor the heat content of saturation water, unit kcal/kg, its computing formula is：

h_lFor the heat content of saturation water, unit kcal/kg；Its computing formula is：

h_g=12500+1.88T-3.7 × 10^-6T^3.2

In above formula, T is vapor (steam) temperature, degrees Celsius.

To reach above-mentioned purpose, the present invention also provides a kind of computational methods of the steam thermal parameter of outlet of steam boiler, Including：

Calculating parameter is obtained, the calculating parameter includes：Steam injection well head steam pressure, temperature, mass dryness fraction, steam injection speed, ground Facial canal line parameter, surface line external environment parameter, material calculation；

According to the calculating parameter, the heat loss amount of outlet of steam boiler to steam injection well head steam is calculated；

According to the calculating parameter, the controlling party of steam drop gradient in surface line is set up by the law of conservation of momentum Journey, determines surface line optional position vapor (steam) temperature and pressure；

Pipeline infinitesimal section is divided in the surface line length according to the material calculation, and sets up energy hole side Journey, using the steam injection well head steam quality as primary condition, by the heat loss, pressure, the mass dryness fraction iterative calculation that intercouple, it is determined that The mass dryness fraction of steam at outlet of steam boiler.

As one kind preferred embodiment, boiler export is taken for the origin of coordinates, steam is Z axis side along pipeline flow direction To according to principle of conservation of momentum, setting up the governing equation of steam drop gradient in surface line：

According to the governing equation, whole surface line is divided into some material calculations with numerical method, each meter Calculation step length is △ z, and above formula is integrated in each section；

Order

v_m=(v_out+v_in)/2

Obtain the computing formula for determining surface line optional position steam pressure：

In above formula, p_inFor the steam pressure of the porch of each material calculation of surface line, unit MPa；p_outFor ground The steam pressure in the exit of each material calculation of facial canal line, unit MPa；f_mFor the coefficient of frictional resistance of moist steam fluid, Dimensionless；ρ_mFor the density of moist steam fluid, unit kilograms per cubic meter；ν_mFor the average speed of moist steam fluid, unit rice/ Second；v_inFor the vapor (steam) velocity of the porch of each material calculation of surface line, unit meter per second；v_outEach for surface line The vapor (steam) velocity in the exit of material calculation, unit meter per second；G is acceleration of gravity, unit rice/square second；r_iFor gas transmission line Internal diameter, unit rice；A is flow section, unit square rice；G for moist steam fluid mass flow, unit Kilograms Per Second；

The ρ_mThe averag density computing formula of saturation moist steam is as follows：

ρ_m=H_gρ_g+(1-H_g)ρ_l

ρ in above formula_lFor the density of saturation water, it is as follows with the relational expression of vapor (steam) temperature T：

ρ_l=0.9967-4.615 × 10^-5T-3.063×10^-6T²

ρ in above formula_gFor the density of saturated vapor, its computing formula is as follows：

ρ_g=5.9 × 10^-4+3.2×10^-4(T/100)^4.5

In above formula, T is vapor (steam) temperature, degrees Celsius；P is steam pressure, unit MPa；

F in above formula_mFor the coefficient of frictional resistance of moist steam, it is according to saturation moist steam under average pressure and mean temperature Reynolds number Re determines；

H_gFor the volumetric quality of saturated vapor, its computing formula is as follows：

In above formula, x is steam quality, nondimensional number；ρ_gFor the density of saturated vapor, unit kilograms per cubic meter；ρ_lIt is full With the density of water, unit kilograms per cubic meter.

As one kind preferred embodiment, steam is saturation moist steam in surface line, calculates any position of surface line The formula for putting vapor (steam) temperature is：

T_in=195.94p_in ^0.225-17.8

In above formula, T_inFor the vapor (steam) temperature of the porch of each material calculation of surface line, degrees Celsius；p_inFor The steam pressure of the porch of each material calculation of surface line, unit MPa.

As one kind preferred embodiment, the mass dryness fraction for determining steam at outlet of steam boiler is comprised the following steps：

Set the default mass dryness fraction drop in the pipeline infinitesimal section；

Mass dryness fraction is calculated according to energy balance law, is iterated, when pipeline infinitesimal section mass dryness fraction drop calculated value and setting When meeting the second predetermined accuracy between value, the mass dryness fraction drop of the pipeline infinitesimal section is determined；

Cycle calculations determine the mass dryness fraction of steam at outlet of steam boiler to whole surface line.

As one kind preferred embodiment, it is described to be included according to energy balance law calculating mass dryness fraction step：

Set up following energy hole equation：

By steam injection well head steam quality x |_Z=L=x_uAs primary condition, above-mentioned equation is solved, obtain surface line any Position steam quality calculation expression formula

Wherein：

C₁=G (h_g-h_l)

So as to boiler export steam quality calculates formula and is：

In above formula, h_gFor the enthalpy of saturated vapor, unit kcal/kg；h_lFor the enthalpy of saturation water, unit kcal/kg；X is Steam quality, nondimensional number；G is acceleration of gravity, unit rice/square second；G be steam injection well head steam displacement, unit kilogram/little When；Q be the unit time in, unit length of pipeline heat loss, unit kilocalorie/(hour rice)；ρ_mFor saturation moist steam density, list Position kilograms per cubic meter；A is line cross-section product, unit square rice；θ be pipeline inclination angle, unit degree；

The ρ_mThe averag density computing formula of saturation moist steam is as follows：

ρ_m=H_gρ_g+(1-H_g)ρ_l

ρ in above formula_lFor the density of saturation water, it is as follows with the relational expression of vapor (steam) temperature T：

ρ_l=0.9967-4.615 × 10^-5T-3.063×10^-6T²

ρ in above formula_gFor the density of saturated vapor, its computing formula is as follows：

ρ_g=5.9 × 10^-4+3.2×10^-4(T/100)^4.5

In above formula, T is vapor (steam) temperature, degrees Celsius；P is steam pressure, unit MPa；

H_gFor the volumetric quality of saturated vapor, its computing formula is as follows：

In above formula, x is steam quality, nondimensional number；ρ_gFor the density of saturated vapor, unit kilograms per cubic meter；ρ_lIt is full With the density of water, unit kilograms per cubic meter.

To reach above-mentioned purpose, the present invention also provides steam thermal parameter computing device in a kind of ground steam injection pipeline, wraps Include：

Parameter acquisition module, for obtaining calculating parameter, the calculating parameter includes：Steam injection well head steam pressure, temperature, Mass dryness fraction, surface line parameter, surface line external environment parameter；

Heat loss determining module, for according to the calculating parameter, iterative calculation outlet of steam boiler to steam injection well head to be steamed The heat loss amount of vapour；

Mass dryness fraction determining module, for fixed according to energy balance under conditions of pressure in surface line, Gravity changer is ignored Rule sets up energy hole equation, determines the mass dryness fraction of steam at outlet of steam boiler.

To reach above-mentioned purpose, the present invention also provides steam thermal parameter computing device in a kind of ground steam injection pipeline, wraps Include：

Parameter acquisition module, for obtaining calculating parameter, the calculating parameter includes：Steam injection well head steam pressure, temperature, Mass dryness fraction, steam injection speed, surface line parameter, surface line external environment parameter, material calculation；

Heat loss determining module, for according to the calculating parameter, iterative calculation outlet of steam boiler to steam injection well head to be steamed The heat loss amount of vapour；

Pressure and temp determining module, for according to the calculating parameter, being set up in surface line by the law of conservation of momentum The governing equation of steam drop gradient, determines surface line optional position vapor (steam) temperature and pressure；

Mass dryness fraction determining module, for pipeline infinitesimal section to be divided in the surface line length according to the material calculation, And set up energy hole equation, using the steam injection well head steam quality as primary condition, by the heat loss that intercouples, pressure, Mass dryness fraction is iterated to calculate, and determines the mass dryness fraction of steam at outlet of steam boiler.

The features and advantages of the invention are：The computational methods of the steam thermal parameter of outlet of steam boiler of the present invention, By obtaining steam injection well head steam pressure, temperature, mass dryness fraction, steam pressure in the surface line is carried out into numerical analysis, set up Steam determines steam along the pressure of surface line arbitrfary point, so that it is determined that injection boiler goes out along surface line pressure equation The steam thermal parameter of mouth, so as to provide reliable basis for the design of Boiler Steam injection parameter.

Further, because the calculating of the heat loss, mass dryness fraction is based on the function of temperature, injection boiler of the present invention The accurate temperature of above-mentioned acquisition is relied in the steam thermal parameter of outlet, according to energy balance law, energy hole side is set up Journey, by cycle calculations the heat loss and mass dryness fraction value of the steam of outlet of steam boiler on surface line are solved, therefore, the application is obtained The heat loss and mass dryness fraction value precision of the steam of the outlet of steam boiler for obtaining is also higher.

With reference to explanation hereinafter and accompanying drawing, only certain exemplary embodiments of this invention is disclose in detail, specify the original of the present invention Reason can be in adopted mode.It should be understood that embodiments of the present invention are not so limited in scope.In appended power In the range of the spirit and terms that profit is required, embodiments of the present invention include many changes, modifications and equivalent.

The feature for describing for a kind of embodiment and/or illustrating can be in same or similar mode one or more It is combined with the feature in other embodiment used in individual other embodiment, or substitute the feature in other embodiment.

It should be emphasized that term "comprises/comprising" refers to the presence of feature, one integral piece, step or component when using herein, but and It is not excluded for the presence of one or more further features, one integral piece, step or component or additional.

Description of the drawings

In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing The accompanying drawing to be used needed for having technology description is briefly described, it should be apparent that, drawings in the following description are only this Some embodiments of invention, for those skilled in the art, without having to pay creative labor, can be with root Other accompanying drawings are obtained according to these accompanying drawings.

The step of Fig. 1 is a kind of computational methods of the steam thermal parameter of outlet of steam boiler in the embodiment of the present invention is schemed；

The step of Fig. 2 is a kind of computational methods of the steam thermal parameter of outlet of steam boiler in the embodiment of the present invention is schemed；

Fig. 3 is a kind of ground steam injection pipeline structural representation in the embodiment of the present invention；

Fig. 4 is a kind of schematic diagram of the computing device of the steam thermal parameter of outlet of steam boiler in the embodiment of the present invention；

Fig. 5 is a kind of schematic diagram of the computing device of the steam thermal parameter of outlet of steam boiler in the embodiment of the present invention.

Specific embodiment

In order that those skilled in the art more fully understand the technical scheme in the application, below in conjunction with the application reality The accompanying drawing in example is applied, the technical scheme in the embodiment of the present application is clearly and completely described, it is clear that described enforcement Example is only some embodiments of the present application, rather than the embodiment of whole.Based on the embodiment in the application, this area is common The every other embodiment that technical staff is obtained on the premise of creative work is not made, should all belong to guarantor of the present invention The scope of shield.

It should be noted that when element is referred to as " being arranged at " another element, it can directly on another element Or can also there is element placed in the middle.When an element is considered as " connection " another element, it can be directly connected to To another element or may be simultaneously present centering elements.Term as used herein " vertical ", " level ", " left side ", For illustrative purposes only, it is unique embodiment to be not offered as " right side " and similar statement.

Unless otherwise defined, all of technology used herein and scientific terminology and the technical field for belonging to the present invention The implication that technical staff is generally understood that is identical.The term for being used in the description of the invention herein is intended merely to description tool The purpose of the embodiment of body, it is not intended that of the invention in limiting.Term as used herein "and/or" includes one or more The arbitrary and all of combination of related Listed Items.

Fig. 1 is referred to, is a kind of step of steam thermal parameter computational methods in ground steam injection pipeline in the embodiment of the present invention Rapid figure.A kind of computational methods of the steam thermal parameter of outlet of steam boiler of the present invention, comprise the steps：

S10, acquisition calculating parameter, the calculating parameter includes：Steam injection well head steam pressure, temperature, mass dryness fraction, surface line Parameter, surface line external environment parameter；

S12, according to the calculating parameter, iterate to calculate the heat loss amount of outlet of steam boiler to steam injection well head steam；

S14, under conditions of pressure in surface line, Gravity changer is ignored energy hole is set up according to energy balance law Equation, determines the mass dryness fraction of steam at outlet of steam boiler.

Specifically, it is described according to the calculating parameter, iterate to calculate the heat waste of outlet of steam boiler to steam injection well head steam Vector (step S12) includes：

First, the default heat insulation layer hull-skin temperature on the pipeline is set；In the present embodiment, the pipe is being set During default heat insulation layer hull-skin temperature on line, the temperature value of the steam that can be measured according to steam injection well head being set, example Temperature such as steam injection well head steam is 300 degrees Celsius, then can set heat insulation layer hull-skin temperature as less than steam injection well head steam The a certain numerical value of temperature, for example, can be 200 degrees Celsius, be beneficial to the number of times for reducing iteration.

Again the pipeline entire thermal resistance is calculated by the default heat insulation layer hull-skin temperature, refers to Fig. 3, surface line by Can be respectively air film layer, heat insulation layer, tube wall, schmutzband, liquid film layer within outer；Wherein, calculating ground is carried out according to following formula Entire thermal resistance R of pipeline：

In above formula, R be surface line thermal resistance value, R₁For steam in surface line and the thermal resistance of liquid film layer heat convection Value, R₂For steam in surface line and the thermal resistance value of schmutzband heat convection, R₃For the thermal resistance value of the heat transfer of tube wall, R₄For exhausted The thermal resistance value of thermosphere heat transfer, R₅For thermal resistance value of the surface line to the forced-convection heat transfer of air, unit is that (rice is little When degree Celsius)/kilocalorie；h_fFor liquid film layer convection transfer rate, h_pFor schmutzband convection transfer rate, h_fcFor heat insulation layer appearance The hot coefficient of forced convection on face, unit is kilocalorie/(square meters per hour degree Celsius)；λ_pFor the heat conduction system of surface line Number, kilocalorie/(meters per hour degree Celsius)；r_iFor surface line inside radius, r_oFor surface line outer radius, r_insOutside for heat insulation layer Radius, unit is rice.

Certainly, when the structure of surface line is different, corresponding its surface line thermal resistance value R can also make adaptive changing Become, here is omitted.

In the present embodiment, surface line includes that heat insulation layer outer surface is right to air to the forced-convection heat transfer of air Stream heat exchange and the radiation heat transfer of pipe outer wall to air；Specifically：

The convection transfer rate h of the heat insulation layer outer surface to air_fc', its computing formula is as follows：

In above formula, λ_aFor the thermal conductivity factor of air, unit kilocalorie/(meters per hour degree Celsius)；Re is Reynolds number, is passed through Following formula is calculated：

Re=ν_aD_s/υ_a

In above formula, ν_aFor wind speed, unit meter per second；υ_aFor the kinematic viscosity of air, unit square meter per second；D_sFor heat insulation layer External diameter, unit rice；Wherein C, n are chosen according to Re according to pre-defined rule.

In the present embodiment, parameter C, n can be chosen according to Re according to table 1.

Table 1

Re	5-80	80-5×103	5×103-5×104	>5×104
					C	0.81	0.625	0.197	0.023
n	0.40	0.46	0.6	0.8

In the present embodiment, the radiation heat transfer coefficient h of pipe outer wall to air_fc", its computing formula is as follows：

In above formula, ε is the outer blackness of tube wall, nondimensional number；T_aFor average temperature of air, degrees Celsius；T_wOutside for heat insulation layer Wall temperature, degrees Celsius.

In the present embodiment, default heat insulation layer hull-skin temperature can be first passed through and calculates pipe outer wall extremely using above-mentioned formula The radiation heat transfer coefficient h of air_fc", then the radiation heat transfer coefficient h for passing through pipe outer wall to air_fc" calculate the total of surface line Thermal resistance R.

Then, pipeline gas transmission is calculated along journey heat loss q by pipeline entire thermal resistance R；Wherein it is possible to using following meter Calculate heat loss q in formula unit of account length surface line：

In above formula, q be the unit time in, the heat loss in unit length surface line, unit kilocalorie/(hour rice)； T_sFor vapor (steam) temperature, degrees Celsius；T_aFor environment temperature, degrees Celsius；R is the entire thermal resistance in unit length surface line Value, unit (meters per hour degree Celsius)/kilocalorie.

In the present embodiment, it is according to the above-mentioned pipeline gas transmission for calculating along journey heat loss q then public using following calculating Formula calculates the calculated value of heat insulation layer hull-skin temperature：

In above formula, h_fFor liquid film layer convection transfer rate, h_pFor schmutzband convection transfer rate, λ_pLeading for surface line Hot coefficient, kilocalorie/(meters per hour degree Celsius)；r_iFor surface line inside radius, r_oFor surface line outer radius, r_insFor thermal insulation Layer outer radius, unit is rice；Q be the unit time in, in unit length surface line in heat loss, unit kilocalorie/(little When rice)；T_sFor vapor (steam) temperature, degrees Celsius；T_wFor heat insulation layer outside wall temperature, degrees Celsius.

Finally iterate, when the heat insulation layer hull-skin temperature calculated value and setting value meet the first predetermined accuracy, The pipeline insulation layer hull-skin temperature is determined, to obtain the heat loss of outlet of steam boiler to steam injection well head steam.

In the present embodiment, first predetermined accuracy can require to be set according to available accuracy, and described first is pre- The value for determining precision set is less, and comparatively, the heat insulation layer hull-skin temperature of acquisition is more accurate, correspondingly, the pipe of acquisition The precision of the heat loss of line is also higher.

In sum, the process for iterating specifically includes：By setting heat insulation layer hull-skin temperature, phase is obtained The entire thermal resistance answered, by the entire thermal resistance corresponding heat loss is obtained, and by the heat loss of the acquisition heat insulation layer is obtained Hull-skin temperature calculated value.

In the present embodiment, it is described to ignore fixed according to energy balance under conditions of pressure in surface line, Gravity changer Rule sets up energy hole equation, and determining the mass dryness fraction (step S13) of steam at outlet of steam boiler includes：

Due to not considering surface line pressure, Gravity changer, it is possible to ignore the change of saturated vapor kinetic energy, potential energy. Therefore following energy hole equation is set up according to energy balance law：

Due to

H=h_gx+h_l(1-x)=L_vx+h_l

So

By steam injection well head steam quality x |_Z=L=x_uAs primary condition, above-mentioned equation is solved, obtain outlet of steam boiler Steam quality calculation expression formula

In above formula, q be unit chronomere length surface line in steam heat loss, unit kilocalorie/(hour rice)； Z is the distance for calculating position and boiler export, unit rice；G be saturated vapor mass flow, unit kg/hr；L_vFor vaporization Latent heat, kcal/kg；x_uFor steam injection well head (surface line end) steam quality, dimensionless.

Wherein, boiler export steam quality calculating formula is obtained during z=0 is：

Above-mentioned latent heat of vaporization L_vThe difference of the heat content of heat content and saturation water for dry saturated steam, unit kcal/kg；At this In embodiment, latent heat of vaporization L_vComputing formula be：

L_v=273 × (374.15-T)^0.38=h_g-h_l；

h_lFor the heat content of saturation water, unit kcal/kg, its computing formula is：

h_lFor the heat content of saturation water, unit kcal/kg；Its computing formula is：

h_g=12500+1.88T-3.7 × 10^-6T^3.2

In above formula, T is vapor (steam) temperature, degrees Celsius.

Fig. 2 is referred to, is a kind of computational methods of the steam thermal parameter of outlet of steam boiler in the embodiment of the present invention Block diagram, steam thermal parameter computational methods comprise the steps in ground steam injection pipeline of the present invention：

Step S20, acquisition calculating parameter, the calculating parameter includes：Steam injection well head steam pressure, temperature, mass dryness fraction, steam injection Speed, surface line parameter, surface line external environment parameter, material calculation.

In this step, the surface line parameter includes：Surface line external diameter, internal diameter, length, outer wall blackness, heat conduction Coefficient, heat insulation layer thickness, insulation material thermal conductivity factor.The surface line external environment parameter includes：Air conduction coefficient, wind Speed, air movement viscosity, environment temperature.In addition, the calculating parameter can also include：Steam injection well head steam displacement.

Step S22, according to the calculating parameter, iterate to calculate the heat loss of outlet of steam boiler to steam injection well head steam Amount；

In this step, first, the default heat insulation layer hull-skin temperature on the pipeline is set；In the present embodiment, When the default heat insulation layer hull-skin temperature on the pipeline is set, the temperature value of the steam that can be measured according to steam injection well head come Set, for example the temperature of steam injection well head steam is 300 degrees Celsius, then can set heat insulation layer hull-skin temperature as less than note The a certain numerical value of vapour well head vapor (steam) temperature, for example, can be 200 degrees Celsius, be beneficial to the number of times for reducing iteration.

Again the pipeline entire thermal resistance is calculated by the default heat insulation layer hull-skin temperature, refers to Fig. 3, surface line by Can be respectively air film layer, heat insulation layer, tube wall, schmutzband, liquid film layer within outer；Wherein, calculating ground is carried out according to following formula Entire thermal resistance R of pipeline：

In above formula, R be surface line thermal resistance value, R₁For steam in surface line and the thermal resistance of liquid film layer heat convection Value, R₂For steam in surface line and the thermal resistance value of schmutzband heat convection, R₃For the thermal resistance value of the heat transfer of tube wall, R₄For exhausted The thermal resistance value of thermosphere heat transfer, R₅For thermal resistance value of the surface line to the forced-convection heat transfer of air, unit is that (rice is little When degree Celsius)/kilocalorie；h_fFor liquid film layer convection transfer rate, h_pFor schmutzband convection transfer rate, h_fcFor heat insulation layer appearance The hot coefficient of forced convection on face, unit is kilocalorie/(square meters per hour degree Celsius)；λ_pFor the heat conduction system of surface line Number, kilocalorie/(meters per hour degree Celsius)；r_iFor surface line inside radius, r_oFor surface line outer radius, r_insOutside for heat insulation layer Radius, unit is rice.

Certainly, when the structure of surface line is different, corresponding its surface line thermal resistance value R can also make adaptive changing Become, here is omitted.

In the present embodiment, surface line includes that heat insulation layer outer surface is right to air to the forced-convection heat transfer of air Stream heat exchange and the radiation heat transfer of pipe outer wall to air；Specifically：

The convection transfer rate h of the heat insulation layer outer surface to air_fc', its computing formula is as follows：

In above formula, λ_aFor the thermal conductivity factor of air, unit kilocalorie/(meters per hour degree Celsius)；Re is Reynolds number, is passed through Following formula is calculated：

Re=ν_aD_s/υ_a

In above formula, ν_aFor wind speed, unit meter per second；υ_aFor the kinematic viscosity of air, unit square meter per second；D_sFor heat insulation layer External diameter, unit rice；Wherein C, n are chosen according to Re according to pre-defined rule.

In the present embodiment, parameter C, n can be chosen according to Re according to table 1.

Table 1

Re	5-80	80-5×103	5×103-5×104	>5×104
					C	0.81	0.625	0.197	0.023
n	0.40	0.46	0.6	0.8

In the present embodiment, the radiation heat transfer coefficient h of pipe outer wall to air_fc", its computing formula is as follows：

In above formula, ε is the outer blackness of tube wall, nondimensional number；T_aFor average temperature of air, degrees Celsius；T_wOutside for heat insulation layer Wall temperature, degrees Celsius.

In the present embodiment, default heat insulation layer hull-skin temperature can be first passed through and calculates pipe outer wall extremely using above-mentioned formula The radiation heat transfer coefficient h of air_fc", then the radiation heat transfer coefficient h for passing through pipe outer wall to air_fc" calculate the total of surface line Thermal resistance R.

Then, pipeline is calculated along journey heat loss q by pipeline entire thermal resistance R；Wherein it is possible to public using following calculating Heat loss q in formula unit of account length surface line：

In above formula, q be the unit time in, in unit length surface line in heat loss, unit kilocalorie/(hour Rice)；T_sFor vapor (steam) temperature, degrees Celsius；T_aFor environment temperature, degrees Celsius；R is total in unit length surface line Thermal resistance value, unit (meters per hour degree Celsius)/kilocalorie.

In the present embodiment, according to the above-mentioned pipeline for calculating along journey heat loss q, then using following computing formula meter Calculate the calculated value of heat insulation layer hull-skin temperature：

In above formula, h_fFor liquid film layer convection transfer rate, h_pFor schmutzband convection transfer rate, λ_pLeading for surface line Hot coefficient, kilocalorie/(meters per hour degree Celsius)；r_iFor surface line inside radius, r_oFor surface line outer radius, r_insFor thermal insulation Layer outer radius, unit is rice；Q be the unit time in, in unit length surface line in heat loss, unit kilocalorie/(little When rice)；T_sFor vapor (steam) temperature, degrees Celsius；T_wFor heat insulation layer outside wall temperature, degrees Celsius.

Finally iterate, when the heat insulation layer hull-skin temperature calculated value and setting value meet the first predetermined accuracy, The pipeline insulation layer hull-skin temperature is determined, to obtain the heat loss amount of outlet of steam boiler to steam injection well head steam.

In the present embodiment, first predetermined accuracy can require to be set according to available accuracy, and described first is pre- The value for determining precision set is less, and comparatively, the heat insulation layer hull-skin temperature of acquisition is more accurate, correspondingly, the pipe of acquisition The precision of the heat loss of line is also higher.

In sum, the process for iterating specifically includes：By setting heat insulation layer hull-skin temperature, phase is obtained The entire thermal resistance answered, by the entire thermal resistance corresponding heat loss is obtained, and by the heat loss of the acquisition heat insulation layer is obtained Hull-skin temperature calculated value.

Step S24, according to the calculating parameter, steam drop gradient in surface line is set up by the law of conservation of momentum Governing equation, determines surface line optional position vapor (steam) temperature and pressure；

In this step, in order to set up the Mathematical Modeling that steam flows in surface line, hypothesis below is done：

1., steam injection well head steam parameter (steam injection speed, pressure, temperature and mass dryness fraction) keeps constant；

2., flowing of the steam in surface line is one-dimensional steady flow.In the ideal case, steam and water are uniformly mixed Close, flow velocity is identical, steam water interface can be regarded as homogeneous (uniform) fluid.

Based on above-mentioned it is assumed that taking boiler export for the origin of coordinates, steam is Z-direction along pipeline flow direction, according to dynamic Amount conservation principle, sets up the governing equation of steam drop gradient in surface line：

According to the governing equation, whole surface line is divided into some material calculations with numerical method, each meter Calculation step length is △ z, and above formula is integrated in each section；

When prediction is along the pressure distribution of whole surface line, whole surface line is divided into some with numerical method Section, each segment length is △ z, and above formula is integrated in each section.

Due to

So

Order

v_m=(v_out+v_in)/2

Then have

So as to obtain the computing formula for determining surface line optional position steam pressure：

In above formula, p_inFor the steam pressure of the porch of each material calculation of surface line, unit MPa；p_outFor ground The steam pressure in the exit of each material calculation of facial canal line, unit MPa；f_mFor the coefficient of frictional resistance of moist steam fluid, Dimensionless；ρ_mFor the density of moist steam fluid, unit kilograms per cubic meter；ν_mFor the average speed of moist steam fluid, unit rice/ Second；v_inFor the vapor (steam) velocity of the porch of each material calculation of surface line, unit meter per second；v_outEach for surface line The vapor (steam) velocity in the exit of material calculation, unit meter per second；G is acceleration of gravity, unit rice/square second；r_iFor gas transmission line Internal diameter, unit rice；A is flow section, unit square rice；G for moist steam fluid mass flow, unit Kilograms Per Second.

The ρ_mThe averag density computing formula of saturation moist steam is as follows：

ρ_m=H_gρ_g+(1-H_g)ρ_l

ρ in above formula_lFor the density of saturation water, it is as follows with the relational expression of vapor (steam) temperature T：

ρ_l=0.9967-4.615 × 10^-5T-3.063×10^-6T²

ρ in above formula_gFor the density of saturated vapor, its computing formula is as follows：

ρ_g=5.9 × 10^-4+3.2×10^-4(T/100)^4.5

In above formula, T is vapor (steam) temperature, degrees Celsius；P is steam pressure, unit MPa；

F in above formula_mFor the coefficient of frictional resistance of moist steam, it is according to saturation moist steam under average pressure and mean temperature Reynolds number Re determines.

Wherein, coefficient of frictional resistance f_mCalculation have various, present embodiment is simultaneously not specifically limited.Specifically, Coefficient of frictional resistance f_mCalculating can adopt Orkiszewski methods, spray coefficient of friction can be according to gas Reynolds number (Re)_g Calculated with liquid film relative roughness, concrete formula is as follows

In above formula, D be gas transmission line diameter, unit rice；v_sgFor gas superficial flow velocity, v_sg=Q_g/ A, unit is meter per second.

Experiment shows that between 0.001～0.5, concrete numerical value needs according to N liquid film relative roughness during spray_wWith under Face formula is calculated：

In above formula, σ be mean temperature, average pressure under liquid film surface tension, units Newtons/rice.

Work as N_wWhen≤0.005, have：

Work as N_w>When 0.005, have：

μ_g=(0.36T+88.37) × 10^-4

In above formula, μ_gFor saturated vapor viscosity, rice pascal second；μ_lWater viscosity, rice pascal second are steamed for saturation；T is Vapor (steam) temperature, degrees Celsius.

In the present embodiment, H_gFor the volumetric quality of saturated vapor, its computing formula is as follows：

In above formula, x is steam quality, nondimensional number；ρ_gFor the density of saturated vapor, unit kilograms per cubic meter；ρ_lIt is full With the density of water, unit kilograms per cubic meter.

In the present embodiment, steam is saturation moist steam in surface line, calculates surface line optional position steam temperature The formula of degree is：

T_in=195.94p_in ^0.225-17.8

In above formula, T_inFor the vapor (steam) temperature of the porch of each material calculation of surface line, degrees Celsius；p_inFor The steam pressure of the porch of each material calculation of surface line, unit MPa.

Step S26, pipeline infinitesimal section is divided in the surface line length according to the material calculation, and set up energy Governing equation, using the steam injection well head steam quality as primary condition, by the heat loss, pressure, the mass dryness fraction iteration meter that intercouple Calculate, determine the mass dryness fraction of steam at outlet of steam boiler.

Because the heat loss of surface line causes the reduction of saturated vapor energy (including potential energy and interior energy), so as to cause to steam The reduction of vapour mass dryness fraction, simultaneously because in pipeline pressure change, cause the change of saturated vapor kinetic energy.So as to flat according to energy Homeostasis is restrained, and sets up following energy hole equation：

By steam injection well head steam quality x |_Z=L=x_uAs primary condition, above-mentioned equation is solved, obtain surface line any Position steam quality calculation expression formula

Wherein：

C₁=G (h_g-h_l)

In above formula, h_gFor the enthalpy of saturated vapor, unit kcal/kg；h_lFor the enthalpy of saturation water, unit kcal/kg；X is Steam quality, nondimensional number；G is acceleration of gravity, unit rice/square second；G be steam injection well head steam displacement, unit kilogram/little When；Q be the unit time in, unit length of pipeline heat loss, unit kilocalorie/(hour rice)；ρ_mFor saturation moist steam density, list Position kilograms per cubic meter；A is line cross-section product, unit square rice；θ be pipeline inclination angle, unit degree.

Wherein, boiler export steam quality calculating formula is obtained during z=0 is：

The ρ_mThe averag density computing formula of saturation moist steam is as follows：

ρ_m=H_gρ_g+(1-H_g)ρ_l

ρ in above formula_lFor the density of saturation water, it is as follows with the relational expression of vapor (steam) temperature T：

ρ_l=0.9967-4.615 × 10^-5T-3.063×10^-6T²

ρ in above formula_gFor the density of saturated vapor, its computing formula is as follows：

ρ_g=5.9 × 10^-4+3.2×10^-4(T/100)^4.5

In above formula, T is vapor (steam) temperature, degrees Celsius；P is steam pressure, unit MPa；

H_gFor the volumetric quality of saturated vapor, its computing formula is as follows：

In above formula, x is steam quality, nondimensional number；ρ_gFor the density of saturated vapor, unit kilograms per cubic meter；ρ_lIt is full With the density of water, unit kilograms per cubic meter.

Specifically, in step S26, the mass dryness fraction for determining steam at outlet of steam boiler is comprised the following steps：

S260, the default mass dryness fraction drop set in the pipeline infinitesimal section；

When the drop of the mass dryness fraction in the pipeline infinitesimal section is set, can based on experience value be set, be beneficial to reduction and change The number of times in generation.For example, the scope that mass dryness fraction is reduced in pre- fixed step size is obtained through statistics, the mass dryness fraction drop may be selected in the system A certain numerical value in the range of meter acquisition.Specifically, for example, through counting in hundred meters of mass dryness fraction between reduction by 0.014 to 0.18, institute State mass dryness fraction drop and may be set to 0.015.

S262, according to energy balance law calculate mass dryness fraction, iterate, when the pipeline infinitesimal section mass dryness fraction drop calculated value with When meeting the second predetermined accuracy between setting value, the mass dryness fraction drop of the pipeline infinitesimal section is determined；

Second predetermined accuracy can require to be set according to available accuracy, and the value of the second predetermined accuracy setting is got over Little, comparatively, the mass dryness fraction drop of the pipeline infinitesimal section of acquisition is more accurate.

S263, cycle calculations determine the mass dryness fraction of steam at outlet of steam boiler to whole surface line.

In the present embodiment, cycle calculations, specifically can be micro- from the first pipeline of boiler export to whole surface line First section, chooses successively, cycle calculations, until well head to well head direction.

In sum, the steam thermal parameter of boiler export is calculated in accordance with the following steps：

(1) (the p with the steam parameter of well head as zequin_i, x_i, G)；

(2) the segment length △ z of surface line one is taken, it is assumed that the mass dryness fraction drop △ x of steam in △ z length_iWith pressure drop △ p_i, Then average mass dryness fraction x of this section_avi=x_i-△x_i/ 2 and average pressure p_avi=p_i-△p_i/ 2, according to p_aviInvestigate and prosecute corresponding average full With temperature T_avi(T_avi=195.94P_avi ^0.225- 17.8) and other physical parameters ρ_l、ρ_g、μ_l、μ_g、H_g、H_l, it is subsequent calculations saturation Averag density ρ of moist steam_mWith coefficient of frictional resistance f_mCalculating prepare, according to the law of conservation of momentum and perfect gas law Calculate the pressure drop △ P in △ z length_i’.By calculated value △ P_i' and assumed value △ p_iRelatively, iterate, Zhi Dao ∣ △ P_i- △P_i’∣/△P_i<Till ε, the inlet pressure p of this section is obtained_i+1With corresponding saturation temperature T_i+1, as the initial value of next △ z. Saturation temperature T is calculated simultaneously_i+1, saturation pressure p_i+1Under enthalpy h_li+1、h_gi+1, it is that the steam quality for calculating this section is prepared.

(3) surface line hull-skin temperature T is assumed_wi, using formula h is calculated_r、h_c, so as to calculate entire thermal resistance and heat waste Lose q_i, then by heat loss q_iSubstitute into ground line spool to heat-insulation layer outer wall computation formula for thermal conduction, obtain pipeline hull-skin temperature T_wi', iterate, Zhi Dao ∣ T_wi-T_wi’∣/T_wi<Till ε, heat loss q is finally obtained_i。

(4) mass dryness fraction x of steam is calculated by energy-balance equation_i, iterate, Zhi Dao ∣ x_i+1-(x_i-△x_i)∣/(x_i-△ x_i)<ε, otherwise repeats above-mentioned (2)-(4) calculation procedure, and by calculated mass dryness fraction x_i+1As the initial mass dryness fraction of next △ z Value.

(5) a △ z are removed, repeats above-mentioned (2)-(5) calculation procedure, until whole ground line line computation is finished, managed Line optional position p_i、T_i、x_i、q_i(i=0,1 ..., N), including steam parameter at boiler export.

The meter of the steam thermal parameter of outlet of steam boiler described in present embodiment is can be seen that by above technical scheme Calculation method, by obtaining steam injection well head steam pressure, temperature, mass dryness fraction, by steam pressure in the surface line numerical value point is carried out Analysis, sets up steam along surface line pressure equation, steam is determined along the pressure of surface line arbitrfary point, so that it is determined that steam injection The steam thermal parameter of boiler export, so as to provide reliable basis for the design of Boiler Steam injection parameter.

Further, because the calculating of the heat loss, mass dryness fraction is based on the function of temperature, injection boiler of the present invention The accurate temperature of above-mentioned acquisition is relied in the computing device of the steam thermal parameter of outlet, according to energy balance law, is set up Energy hole equation, by cycle calculations the heat loss and mass dryness fraction value of the steam of outlet of steam boiler on surface line are solved, therefore, The heat loss and mass dryness fraction value precision of the steam of the outlet of steam boiler that the application is obtained is also higher.

Fig. 4 is referred to, the computing device of steam thermal parameter in a kind of ground steam injection pipeline, including：

Parameter acquisition module 20, for obtaining calculating parameter, the calculating parameter includes：Steam injection well head steam pressure, temperature Degree, mass dryness fraction, surface line parameter, surface line external environment parameter；

Heat loss determining module 22, for according to the calculating parameter, iterative calculation outlet of steam boiler to be to steam injection well head The heat loss amount of steam；

Mass dryness fraction determining module 24, under conditions of pressure in surface line, Gravity changer is ignored according to energy balance Law sets up energy hole equation, determines the mass dryness fraction of steam at outlet of steam boiler.

Fig. 5 is referred to, the computing device of steam thermal parameter in a kind of ground steam injection pipeline, including：

Parameter acquisition module 20, for obtaining calculating parameter, the calculating parameter includes：Steam injection well head steam pressure, temperature Degree, mass dryness fraction, steam injection speed, surface line parameter, surface line external environment parameter, material calculation；

Heat loss determining module 22, for according to the calculating parameter, iterative calculation outlet of steam boiler to be to steam injection well head The heat loss amount of steam；

Pressure and temp determining module 24, for according to the calculating parameter, by the law of conservation of momentum surface line being set up The governing equation of middle steam drop gradient, determines surface line optional position vapor (steam) temperature and pressure；

Mass dryness fraction determining module 26, for pipeline infinitesimal to be divided in the surface line length according to the material calculation Section, and energy hole equation is set up, using the steam injection well head steam quality as primary condition, by the heat loss, the pressure that intercouple Power, mass dryness fraction iterative calculation, determine the mass dryness fraction of steam at outlet of steam boiler.

The meter of the steam thermal parameter of outlet of steam boiler described in present embodiment is can be seen that by above technical scheme Device is calculated, by obtaining steam injection well head steam pressure, temperature, mass dryness fraction, steam pressure in the surface line numerical value point is carried out into Analysis, sets up steam along surface line pressure equation, steam is determined along the pressure of surface line arbitrfary point, so that it is determined that steam injection The steam thermal parameter of boiler export, so as to provide reliable basis for the design of Boiler Steam injection parameter.

Further, because the calculating of the heat loss, mass dryness fraction is based on the function of temperature, injection boiler of the present invention The accurate temperature of above-mentioned acquisition is relied in the computing device of the steam thermal parameter of outlet, according to energy balance law, is set up Energy hole equation, by cycle calculations the heat loss and mass dryness fraction value of the steam of outlet of steam boiler on surface line are solved, therefore, The heat loss and mass dryness fraction value precision of the steam of the outlet of steam boiler that the application is obtained is also higher.

Herein cited any digital value all include between lower limit to higher limit with the lower value of an incremented and The all values of upper value, the interval that there are at least two units between any lower value and any much higher value.For example, such as Fruit elaborates that the value of the quantity or process variable (such as temperature, pressure, time etc.) of a part is from 1 to 90, preferably from 20 To 80, more preferably from 30 to 70, then such as 15 to 85,22 are also clearly listed during purpose is to illustrate the specification and is arrived 68th, 43 to 51,30 to 32 is equivalent.For the value less than 1, suitably think that a unit is 0.0001,0.001,0.01,0.1. These are only intended to the example clearly expressed, it is believed that the numerical value enumerated between minimum and peak is possible to Combination is all expressly set forth in the specification in a similar manner.

Unless otherwise stated, all scopes all include all numerals between end points and end points.It is used together with scope " about " or " approximate " be suitable for two end points of the scope.Thus, " about 20 to 30 " are intended to cover that " about 20 to about 30 ", at least including the end points for indicating.

The all articles for disclosing and reference, including patent application and publication, for various purposes by quoting knot Together in this.The term " substantially by ... constitute " of description combination should include determined by element, composition, part or step and reality Other elements, composition, part or the step of the basic novel feature of the combination are not affected in matter.Using term "comprising" or " including " is describing the combination of element here, composition, part or step it is also contemplated that basic by these elements, composition, part Or the embodiment that step is constituted.Here by using term " can with ", it is intended to which illustrate that " can with " include is described any Attribute is all optional.

Multiple element, composition, part or step can be provided by single integrated component, composition, part or step.Alternative Ground, single integrated component, composition, part or step can be divided into detached multiple element, composition, part or step.It is used for The open "a" or "an" of description element, composition, part or step is not said to exclude other elements, composition, part Or step.

It should be understood that above description is to illustrate rather than to be limited.By reading above-mentioned retouching State, many embodiments and many applications outside the example for being provided all will be for a person skilled in the art aobvious and easy See.Therefore, the scope of this teaching should not determine with reference to foregoing description, but should with reference to claims and this The four corner of the equivalent that a little claims are possessed is determining.It is for comprehensive purpose, all articles and special with reference to including The disclosure of profit application and bulletin is all by reference to being incorporated herein.Theme disclosed herein is omitted in aforementioned claim Any aspect is not intended to abandon the body matter, also should not be considered as inventor the theme is not thought of as it is disclosed A part for subject matter.

Claims (13)

1. computational methods of the steam thermal parameter of a kind of outlet of steam boiler, it is characterised in that include：

Calculating parameter is obtained, the calculating parameter includes：Steam injection well head steam pressure, temperature, mass dryness fraction, surface line parameter, ground Facial canal line external environment parameter；

According to the calculating parameter, the heat loss amount of outlet of steam boiler to steam injection well head steam is iterated to calculate；

Ignore and energy hole equation is set up according to energy balance law under conditions of pressure in surface line, Gravity changer, it is determined that The mass dryness fraction of steam at surface line outlet of steam boiler.

2. computational methods as claimed in claim 1, it is characterised in that the calculating outlet of steam boiler is to steam injection well head steam Heat loss amount include：

Set the default heat insulation layer hull-skin temperature on the pipeline；

The pipeline entire thermal resistance is calculated by the default heat insulation layer hull-skin temperature, pipeline is calculated by the pipeline entire thermal resistance Gas transmission is along journey heat loss；Heat insulation layer hull-skin temperature is calculated along journey heat loss according to the pipeline gas transmission；

Iterate, when the heat insulation layer hull-skin temperature calculated value and setting value meet the first predetermined accuracy, it is determined that described Pipeline insulation layer hull-skin temperature, to obtain the heat loss of outlet of steam boiler to steam injection well head steam.

3. computational methods as claimed in claim 2, it is characterised in that using following computing formula unit of account length ground Heat loss in pipeline：

$q=\frac{T_s-T_a}{R}$

In above formula, q be the unit time in, in unit length surface line in heat loss, unit kilocalorie/(hour rice)；T_sFor Vapor (steam) temperature, degrees Celsius；T_aFor environment temperature, degrees Celsius；R is the thermal resistance value in unit length surface line, Unit (meters per hour degree Celsius)/kilocalorie；

By the product of the heat loss in the numerical value of the material calculation and the unit length surface line, the ground is determined Heat loss in pipeline.

4. computational methods as claimed in claim 3, it is characterised in that the calculating surface line entire thermal resistance includes：

Entire thermal resistance R of surface line, is calculated according to following formula：

$\begin{array}{c}R=\underset{i=1}{\overset{5}{\&Sigma;}}{R}_i=R_1+R_2+R_3+R_4+R_5\\ =\frac{1}{2\mathrm{\&pi;}}(\frac{1}{h_f{r}_i}+\frac{1}{h_p{r}_i}+\frac{1}{{\mathrm{\&lambda;}}_p}\ln \frac{r_o}{r_i}+\frac{1}{{\mathrm{\&lambda;}}_{ins}}\ln \frac{r_{ins}}{r_o}+\frac{1}{h_{fc}{r}_{ins}})\end{array}$

In above formula, R be surface line thermal resistance value, R₁For steam in surface line and the thermal resistance value of liquid film layer heat convection, R₂For The thermal resistance value of steam and schmutzband heat convection, R in surface line₃For the thermal resistance value of the heat transfer of tube wall, R₄Pass for heat insulation layer heat The thermal resistance value led, R₅For thermal resistance value of the surface line to the forced-convection heat transfer of air, unit is that (meters per hour is Celsius Degree)/kilocalorie；h_fFor liquid film layer convection transfer rate, h_pFor schmutzband convection transfer rate, h_fcTo force on heat insulation layer outer surface Advection heat coefficient, unit is kilocalorie/(square meters per hour degree Celsius)；λ_pFor the thermal conductivity factor of surface line, kilocalorie/ (meters per hour degree Celsius)；r_iFor surface line inside radius, r_oFor surface line outer radius, r_insFor heat insulation layer outer radius, list Position is rice；

Wherein, surface line includes the heat convection and pipe outer wall of heat insulation layer outer surface to air to the forced-convection heat transfer of air To the radiation heat transfer of air；

The convection transfer rate h of the heat insulation layer outer surface to air_fc', its computing formula is as follows：

${h_{fc}}^{\&prime;}=C\frac{{\mathrm{\&lambda;}}_a}{D_s}{\mathrm{Re}}^n$

In above formula, λ_aFor the thermal conductivity factor of air, unit kilocalorie/(meters per hour degree Celsius)；Re is Reynolds number, by following formula It is calculated：

Re=ν_aD_s/υ_a

In above formula, ν_aFor wind speed, unit meter per second；υ_aFor the kinematic viscosity of air, unit square meter per second；D_sFor heat insulation layer external diameter, Unit rice；Wherein C, n are chosen according to Re according to pre-defined rule；

The radiation heat transfer coefficient h of pipe outer wall to air_fc", its computing formula is as follows：

${h_{fc}}^{\&prime;\&prime;}=5.67\mathrm{\&epsiv;}\&lsqb;{\left(\frac{T_w+273}{100}\right)}^4-{\left(\frac{T_a+273}{100}\right)}^4\&rsqb;/(T_w-T_a)$

In above formula, ε is the outer blackness of tube wall, nondimensional number；T_aFor average temperature of air, degrees Celsius；T_wFor the outer wall temperature of heat insulation layer Degree, degrees Celsius.

5. computational methods as claimed in claim 4, it is characterised in that heat insulation layer outer surface is calculated using following computing formula Temperature：

$T_w=T_s-\frac{q}{2\mathrm{\&pi;}}(\frac{1}{h_f{r}_i}+\frac{1}{h_p{r}_i}+\frac{1}{{\mathrm{\&lambda;}}_p}ln\frac{r_o}{r_i}+\frac{1}{{\mathrm{\&lambda;}}_{ins}}ln\frac{r_{ins}}{r_o})$

In above formula, h_fFor liquid film layer convection transfer rate, h_pFor schmutzband convection transfer rate, λ_pFor the heat conduction system of surface line Number, kilocalorie/(meters per hour degree Celsius)；r_iFor surface line inside radius, r_oFor surface line outer radius, r_insOutside for heat insulation layer Radius, unit is rice；Q be the unit time in, in unit length surface line in heat loss, unit kilocalorie/(hour Rice)；T_sFor vapor (steam) temperature, degrees Celsius；T_wFor heat insulation layer outside wall temperature, degrees Celsius.

6. computational methods as claimed in claim 5, it is characterised in that described that mass dryness fraction step bag is calculated according to energy balance law Include：

Set up following energy hole equation：

$G\frac{dh}{dz}+q=0$

By steam injection well head steam quality x |_Z=L=x_uAs primary condition, above-mentioned equation is solved, obtain the steaming of outlet of steam boiler Vapour mass dryness fraction calculation expression

$x\left(z\right)=x_u+\frac{qz}{{\mathrm{GL}}_v}$

So as to the steam quality of boiler export calculates formula and is：

$x_o=x_u+\frac{qL}{{\mathrm{GL}}_v}$

In above formula, q be unit chronomere length surface line in steam heat loss, unit kilocalorie/(hour rice)；Z is Calculate the distance of position and boiler export, unit rice；G be saturated vapor mass flow, unit kg/hr；L_vIt is latent for vaporization Heat, kcal/kg；x_uFor steam injection well head (surface line end) steam quality, dimensionless；

Above-mentioned latent heat of vaporization L_vThe difference of the heat content of heat content and saturation water for dry saturated steam, its computing formula is：

L_v=273 × (374.15-T)^0.38=h_g-h_l；

h_lFor the heat content of saturation water, unit kcal/kg, its computing formula is：

h_lFor the heat content of saturation water, unit kcal/kg；Its computing formula is：

h_g=12500+1.88T-3.7 × 10^-6T^3.2

In above formula, T is vapor (steam) temperature, degrees Celsius.

7. computational methods of the steam thermal parameter of a kind of outlet of steam boiler, it is characterised in that include：

Calculating parameter is obtained, the calculating parameter includes：Steam injection well head steam pressure, temperature, mass dryness fraction, steam injection speed, ground line Line parameter, surface line external environment parameter, material calculation；

According to the calculating parameter, the heat loss amount of outlet of steam boiler to steam injection well head steam is calculated；

According to the calculating parameter, the governing equation of steam drop gradient in surface line is set up by the law of conservation of momentum, really Determine surface line optional position vapor (steam) temperature and pressure；

Pipeline infinitesimal section is divided in the surface line length according to the material calculation, and sets up energy hole equation, with The steam injection well head steam quality, by the heat loss, pressure, the mass dryness fraction iterative calculation that intercouple, determines steam injection as primary condition The mass dryness fraction of steam at boiler export.

8. computational methods as claimed in claim 7, it is characterised in that take boiler export for the origin of coordinates, steam is along pipeline stream Dynamic direction is Z-direction, according to principle of conservation of momentum, sets up the governing equation of steam drop gradient in surface line：

$-\frac{dp}{dz}={\mathrm{\&rho;}}_{m}gsin\mathrm{\&theta;}+\frac{f_m{\mathrm{GV}}_m}{2r_{i}A}-\frac{GQ}{A^{2}p}\frac{dp}{dz}$

According to the governing equation, whole surface line is divided into some material calculations with numerical method, each calculates step Length is △ z, and above formula is integrated in each section；

Order

v_m=(v_out+v_in)/2

Obtain the computing formula for determining surface line optional position steam pressure：

$p_{in}=p_{out}+\&lsqb;\frac{f_m{\mathrm{\&rho;}}_m\mathrm{\&Delta;}z{(v_{out}+v_{in})}^2}{8r_i}+{\mathrm{\&rho;}}_{m}g\sin \mathrm{\&theta;}\mathrm{\&Delta;}z+\frac{G}{A}(v_{out}-v_{in})\&rsqb;$

In above formula, p_inFor the steam pressure of the porch of each material calculation of surface line, unit MPa；p_outFor ground line The steam pressure in the exit of each material calculation of line, unit MPa；f_mIt is immeasurable for the coefficient of frictional resistance of moist steam fluid Guiding principle；ρ_mFor the density of moist steam fluid, unit kilograms per cubic meter；ν_mFor the average speed of moist steam fluid, unit meter per second；v_in For the vapor (steam) velocity of the porch of each material calculation of surface line, unit meter per second；v_outEach for surface line is calculated The vapor (steam) velocity in the exit of step-length, unit meter per second；G is acceleration of gravity, unit rice/square second；r_iFor in gas transmission line Footpath, unit rice；A is flow section, unit square rice；G for moist steam fluid mass flow, unit Kilograms Per Second；

The ρ_mThe averag density computing formula of saturation moist steam is as follows：

ρ_m=H_gρ_g+(1-H_g)ρ_l

ρ in above formula_lFor the density of saturation water, it is as follows with the relational expression of vapor (steam) temperature T：

ρ_l=0.9967-4.615 × 10^-5T-3.063×10^-6T²

ρ in above formula_gFor the density of saturated vapor, its computing formula is as follows：

ρ_g=5.9 × 10^-4+3.2×10^-4(T/100)^4.5

In above formula, T is vapor (steam) temperature, degrees Celsius；P is steam pressure, unit MPa；

F in above formula_mFor the coefficient of frictional resistance of moist steam, its Reynolds according to saturation moist steam under average pressure and mean temperature Number Re determines；

H_gFor the volumetric quality of saturated vapor, its computing formula is as follows：

$H_g=\frac{x}{x+(1-x)\frac{{\mathrm{\&rho;}}_g}{{\mathrm{\&rho;}}_l}}$

In above formula, x is steam quality, nondimensional number；ρ_gFor the density of saturated vapor, unit kilograms per cubic meter；ρ_lFor saturation water Density, unit kilograms per cubic meter.

9. computational methods as claimed in claim 8, it is characterised in that steam is saturation moist steam in surface line, calculates ground The formula of facial canal line optional position vapor (steam) temperature is：

T_in=195.94p_in ^0.225-17.8

In above formula, T_inFor the vapor (steam) temperature of the porch of each material calculation of surface line, degrees Celsius；p_inFor ground line The steam pressure of the porch of each material calculation of line, unit MPa.

10. computational methods as claimed in claim 9, it is characterised in that the mass dryness fraction of steam at the determination outlet of steam boiler Comprise the following steps：

Set the default mass dryness fraction drop in the pipeline infinitesimal section；

Mass dryness fraction is calculated according to energy balance law, is iterated, when the pipeline infinitesimal section mass dryness fraction drop calculated value and setting value it Between when meeting the second predetermined accuracy, determine the mass dryness fraction drop of the pipeline infinitesimal section；

Cycle calculations determine the mass dryness fraction of steam at outlet of steam boiler to whole surface line.

11. computational methods as claimed in claim 10, it is characterised in that described that mass dryness fraction step is calculated according to energy balance law Including：

Set up following energy hole equation：

$G\&lsqb;(h_g-h_l)\frac{dx}{dz}+\frac{{\mathrm{dh}}_l}{dp}\frac{dp}{dz}+(\frac{{\mathrm{dh}}_g}{dp}-\frac{{\mathrm{dh}}_l}{dp})\frac{dp}{dz}x+\frac{G^2}{A^2}\frac{1}{{\mathrm{\&rho;}}_m}\frac{d}{dz}\left(\frac{1}{{\mathrm{\&rho;}}_m}\right)+g\sin \mathrm{\&theta;}\&rsqb;+q=0$

By steam injection well head steam quality x |_Z=L=x_uAs primary condition, above-mentioned equation is solved, obtain surface line optional position Steam quality calculation expression formula

$x\left(z\right)=e^{-\frac{C_2}{C_1}(-(L-z\left)\right)}\&lsqb;-\frac{C_3}{C_2}{e}^{\frac{C_2}{C_1}(-(L-z\left)\right)}+x_u+\frac{C_3}{C_2}\&rsqb;$

Wherein：

C₁=G (h_g-h_l)

$C_2=G\&lsqb;(\frac{{\mathrm{dh}}_g}{dp}-\frac{{\mathrm{dh}}_l}{dp})\frac{dp}{dz}\&rsqb;$

$C_3=q+G\&lsqb;\frac{{\mathrm{dh}}_l}{dp}\frac{dp}{dz}+\frac{G^2}{A^2}\frac{1}{{\mathrm{\&rho;}}_m}\frac{d}{dz}\left(\frac{1}{{\mathrm{\&rho;}}_m}\right)\&rsqb;$

So as to boiler export steam quality calculates formula and is：

$x_o=e^{\frac{C_2}{C_1}L}\&lsqb;-\frac{C_3}{C_2}{e}^{\frac{C_2}{C_1}(-L)}+x_u+\frac{C_3}{C_2}\&rsqb;$

In above formula, h_gFor the enthalpy of saturated vapor, unit kcal/kg；h_lFor the enthalpy of saturation water, unit kcal/kg；X is steam Mass dryness fraction, nondimensional number；G is acceleration of gravity, unit rice/square second；G be steam injection well head steam displacement, unit kg/hr；q For in the unit time, unit length of pipeline heat loss, unit kilocalorie/(hour rice)；ρ_mFor saturation moist steam density, unit thousand Gram/cubic metre；A is line cross-section product, unit square rice；θ be pipeline inclination angle, unit degree；

The ρ_mThe averag density computing formula of saturation moist steam is as follows：

ρ_m=H_gρ_g+(1-H_g)ρ_l

ρ in above formula_lFor the density of saturation water, it is as follows with the relational expression of vapor (steam) temperature T：

ρ_l=0.9967-4.615 × 10^-5T-3.063×10^-6T²

ρ in above formula_gFor the density of saturated vapor, its computing formula is as follows：

ρ_g=5.9 × 10^-4+3.2×10^-4(T/100)^4.5

In above formula, T is vapor (steam) temperature, degrees Celsius；P is steam pressure, unit MPa；

H_gFor the volumetric quality of saturated vapor, its computing formula is as follows：

$H_g=\frac{x}{x+(1-x)\frac{{\mathrm{\&rho;}}_g}{{\mathrm{\&rho;}}_l}}$

In above formula, x is steam quality, nondimensional number；ρ_gFor the density of saturated vapor, unit kilograms per cubic meter；ρ_lFor saturation water Density, unit kilograms per cubic meter.

Steam thermal parameter computing device in a kind of 12. ground steam injection pipelines, it is characterised in that include：

Parameter acquisition module, for obtaining calculating parameter, the calculating parameter includes：It is steam injection well head steam pressure, temperature, dry Degree, surface line parameter, surface line external environment parameter；

Heat loss determining module, for according to the calculating parameter, iterative calculation outlet of steam boiler to be to steam injection well head steam Heat loss amount；

Mass dryness fraction determining module, for being built according to energy balance law under conditions of pressure in surface line, Gravity changer is ignored Vertical energy hole equation, determines the mass dryness fraction of steam at outlet of steam boiler.

Steam thermal parameter computing device in a kind of 13. ground steam injection pipelines, it is characterised in that include：

Parameter acquisition module, for obtaining calculating parameter, the calculating parameter includes：It is steam injection well head steam pressure, temperature, dry Degree, steam injection speed, surface line parameter, surface line external environment parameter, material calculation；

Heat loss determining module, for according to the calculating parameter, iterative calculation outlet of steam boiler to be to steam injection well head steam Heat loss amount；

Pressure and temp determining module, for according to the calculating parameter, by the law of conservation of momentum steam in surface line being set up The governing equation of pressure drop gradient, determines surface line optional position vapor (steam) temperature and pressure；

Mass dryness fraction determining module, for pipeline infinitesimal section to be divided in the surface line length according to the material calculation, and builds Vertical energy hole equation, using the steam injection well head steam quality as primary condition, by the heat loss, pressure, the mass dryness fraction that intercouple Iterative calculation, determines the mass dryness fraction of steam at outlet of steam boiler.