CN106052006A - Temperature and humidity weak correlation control method for air conditioning system - Google Patents

Abstract

The invention relates to a temperature and humidity weak correlation control method for an air conditioning system. The method is characterized by comprising the following steps that firstly, the supply air temperature is controlled by adjusting the evaporation temperature or condensation temperature of a heat exchanger; and secondly, and the supply air humidity is controlled by adjusting the duration time of moisture absorption or moisture liberation of the heat exchanger. Compared with air adjusting device control strategies in issued patents or other documents, the method has the following advantages that firstly, the characteristic of weak correlation of the heat transfer and mass transfer processes of the heat-mass weak coupling heat exchanger is brought into full play, so that the independent temperature-humidity control flexibility of the temperature and humidity weak correlation control air conditioning system is improved, and high efficiency of the air conditioning system is fully guaranteed; and secondly, the control strategy is different from the previous control strategy which takes temperature control or humidity control as the principal thing, simultaneous control over temperature and humidity is realized, and thus the air supply comfort level of the air conditioning system is greatly improved.

Description

Air conditioning system humiture weak rigidity control method

Technical field

The present invention relates to the control method of a kind of conditioner, utilize caloic weak coupling transmission to change particularly to one The air conditioning system that hot device builds, in order to realize its wind pushing temperature (sensible heat transfer ability) and air-supply water capacity (latent heat disposal ability) The independent requirement controlled and the control method that designs.

Background technology

The material with moisture absorbing is coated in the surface of heat exchanger, and may make up one can be carried out efficiently air latent heat The heat exchanger processed.Finned tube exchanger in traditional vapor compressing refrigeration system is replaced with this surface-coated and has dehumidizer Heat exchanger hereinafter referred to as dehumidification heat exchange, form a kind of efficient fresh air dehumidifier hereinafter referred to as adsorption and dehumidification machine, had Following conditioner such as, Chinese patent CN 1864033A, CN 101171459A, it may be assumed that at one containing multiple heat exchange In the vapor-compression refrigerant cycle of device, at least a heat exchanger is dehumidification heat exchange, utilizes dehumidification heat exchange to carry out air Humidity regulation, the heat exchanger or the other air conditioning system that recycle other carry out temperature regulation to air.

Aforesaid hygroscopic agent coating heat exchanger, in published patent or other document, it is significantly characterised by main Want or be served only for processing the humidity load of new wind, and the sensible heat load of new wind and latent heat load need nonetheless remain for extra heat transmission equipment or Person's air conditioning system goes to process.Hence in so that the space that whole air conditioning system takies is big, the initial cost of system is high, and system controls numerous Trivial.Therefore, the heat exchanger that the caloic weak coupling of such issues that prior art proposes a kind of solution in succession is transmitted, and based on this Room air conditioner designed by class heat exchanger, had both met the requirement efficiently processing latent heat load, also met efficiently process aobvious The requirement of thermic load；Both improve the comfortableness of air-supply, maintain again whole air conditioning system compact conformation.But at actual motion During using, often face the change of air conditioning condition and deviate original design conditions, if conservative control can not be carried out, The performance of the most whole air conditioning system will severe exacerbation.

Summary of the invention

For defect of the prior art, it is an object of the invention to provide a kind of sky that air conditioning system is realized conservative control Adjusting system humiture weak rigidity control method.

For solving above-mentioned technical problem, one air conditioning system humiture weak rigidity control method of the present invention, it is characterised in that Comprise the steps:

Step 1, the evaporating temperature of regulation heat exchanger or condensation temperature are to realize the control to wind pushing temperature；

Step 2, the moisture absorption of regulation heat exchanger or the persistent period of moisture releasing are to realize the control to blasting humidity.

Preferably, ε-NTU method is used to determine evaporating temperature or condensation temperature T_evap, evaporating temperature or condensation temperature T_evapFull Foot:

T_out=T_in-(T_in-T_evap)(1-e^-NTU)

Wherein, T_outFor wind pushing temperature, T_inFor heat exchanger inlet temperature, T_evapFor evaporation or condensation temperature, NTU is heat exchange Device number of transfer units.

Preferably, heat exchanger heat transfer unit number NTU meets:

$NTU=\frac{hA}{G_a{C}_{p,a}}$

Wherein, G_aFor the mass flow of handled air, C_p,aFor the specific heat capacity of handled air, h is air side sensible heat pair The stream coefficient of heat transfer, A is air side heat exchange area.

Preferably, step 2 includes:

Step 2.1, equal moisture absorption rate when setting upAnd the curve linear relationship between the persistent period τ of moisture absorption or moisture releasing；

Step 2.2, equal moisture absorption rate when determining

Step 2.3, determines blasting humidity.

Preferably, in step 2.1, the time equal moisture absorption rate of unit mass hygroscopic agentMeet:

${\stackrel{\‾}{w}}_n=\frac{\underset{j=1}{\overset{n}{\Σ}}{\mathrm{\ρ}}_a\×Q_a\×({\mathrm{di}}_j-{\mathrm{do}}_j)\×t_0}{m\×n\×t_0}$

Wherein, ρ_aRepresent air intake density, Q_aRepresent intake, (di_j-do_j) represent that the humidity of jth heat exchanger both sides passes The difference of sensor reading, m represents the gross mass of hygroscopic agent coated on heat exchanger, and n represents positive integer, t₀Represent that epidemic disaster passes The data collection interval of sensor；

The persistent period τ of moisture absorption or moisture releasing meets:

τ=n × t₀。

Preferably, step 2.2, equal moisture absorption rate when determiningMeet:

$\stackrel{\‾}{w}={\mathrm{\Δw}}_t/\mathrm{\τ}$

Wherein, Δ w_tThe representation unit quality hygroscopic agent total hygroscopic capacity in the persistent period τ of moisture absorption or moisture releasing, τ represents Moisture absorption or the persistent period of moisture releasing.

Preferably, in step 2.2, the unit mass hygroscopic agent total hygroscopic capacity Δ in the persistent period τ of moisture absorption or moisture releasing w_tMeet:

$\stackrel{\‾}{w}=\frac{w1-w2}{\mathrm{\τ}}(1-e^{-k\×\mathrm{\τ}})$

Wherein, w1 represents that, under evaporating state, unit mass hygroscopic agent reaches water capacity during saturated moisture absorption；W2 represents Under condensing state, unit mass hygroscopic agent reaches water capacity during saturated moisture absorption；K represents moisture absorption rate constant.

Preferably, in step 2.3, according to time equal moisture absorption rate determine blasting humidity d_ao, blasting humidity d_aoMeet:

$\stackrel{\‾}{w}=G_a(d_{ai}-d_{ao})/m$

Wherein, G_aRepresent the air quantity by vaporizer；M represents the gross mass of hygroscopic agent coated on heat exchanger；d_aiTable Show the water capacity of evaporator air.

The present invention has following excellent relative to the conditioner control strategy in published patent or other document Point:

(1) give full play to caloic weak coupling heat exchanger heat transfer and the feature of mass transport process weak rigidity, thus both improve temperature Humidity weak rigidity controls air conditioning system and realizes the motility of independent temperature-humidity control and fully ensured that again the height of described air conditioning system Effect property；

(2) described control strategy different from the past based on temperature control or the control plan based on humid control Slightly, but achieve humiture and control simultaneously, thus drastically increase the air-supply comfortableness telling air conditioning system.

Accompanying drawing explanation

By the detailed description non-limiting example made with reference to the following drawings of reading, the further feature of the present invention, Purpose and advantage will become more apparent upon.

Fig. 1 is the time equal moisture absorption rate curve chart of air conditioning system humiture weak rigidity control method hygroscopic agent of the present invention；

Fig. 2 is that the time equal moisture absorption rate curve experiments of air conditioning system humiture weak rigidity control method hygroscopic agent of the present invention is surveyed Examination schematic diagram.

Detailed description of the invention

Below embodiments of the invention are elaborated: the present embodiment is carried out under premised on technical solution of the present invention Implement, give detailed embodiment and concrete operating process.It should be pointed out that, to those of ordinary skill in the art For, without departing from the inventive concept of the premise, it is also possible to make some deformation and improvement, these broadly fall into the guarantor of the present invention Protect scope.

First the present invention regulates evaporating temperature or condensation temperature meets the requirement of wind pushing temperature (sensible heat load)；Then basis Under specified temp, the time equal moisture absorption rate curve of hygroscopic agent determines that moisture absorption/moisture releasing process duration is to meet blasting humidity The requirement of (latent heat load).

Specifically, the present invention is realized by the following method:

First, determine, according to ε-NTU method or other experimental technique, evaporating temperature Te met required for wind pushing temperature, Wherein the sensible heat convection transfer rate h of air side can be according to empirical equation corresponding to the heat exchanger structure used or other simulation Software calculates.

Described ε-NTU method can be expressed as:

T_out=T_in-(T_in-T_evap)(1-e^-NTU), wherein T_outFor leaving air temp, T_inFor heat exchanger inlet temperature, T_evapFor Evaporation or condensation temperature, NTU is heat exchanger heat transfer unit number, and NTU can be defined by following formula,

G_aFor the mass flow of handled air, C_p,aFor the specific heat capacity of handled air, h is air side Sensible heat convection transfer rate, A is air side heat exchange area.

Second, according to required air-out humidity, equal moisture absorption rate when calculating corresponding by following formula

$\stackrel{\‾}{w}=G_a(d_{ai}-d_{ao})/m_s$

Wherein Ga is the air quantity by vaporizer, kg/s；Ms is the gross mass of hygroscopic agent coated on heat exchanger, kg； Dai refers to the water capacity of evaporator air, and dao is the air-supply water capacity of requirement, kg/kg dry air.Then look up the first step On average moisture absorption rate curve (such as Fig. 1) corresponding to evaporating temperature Te obtained byThe corresponding moisture absorption process persistent period τ。

Average moisture absorption rate of the present inventionRefer to that the unit mass hygroscopic agent total hygroscopic capacity in time τ is with used The ratio of time τ, can be defined by following formula,

Wherein Δ w_tThe representation unit quality hygroscopic agent total hygroscopic capacity in time τ.Especially, moisture absorption is told The Δ w of agent_tThe change of t in time can be estimated by following formula,

Δw_t=Δ w_∞×(1-e^-k×t), wherein Δ w_∞Representation unit quality hygroscopic agent maximum possible in a cycle Hygroscopic capacity, k represents moisture absorption rate constant.Described circulation refer to hygroscopic agent two duties periodically repeat moisture absorption and Moisture releasing process, one of them duty refer to described heat exchanger as vaporizer, evaporating temperature is Te, and inlet temperature is Ta1, enters Wind water capacity is da1, and water capacity when now unit mass hygroscopic agent reaches saturated moisture absorption is w1；Another duty refers to institute Stating heat exchanger as condenser, condensation temperature is Tc, and inlet temperature is Ta2, and air intake water capacity is da2, and now hygroscopic agent reaches Water capacity during saturated moisture absorption is w2.Therefore,

Δw_∞=w1-w2

According to above rational analysis, average moisture absorption rate of the present inventionCan be estimated by following formula,When the time, τ was shorter (such as τ ＜ 10 minutes),Can be further simplified as,

$\stackrel{\‾}{w}=k(w1-w2)(1-0.5\×k\×\mathrm{\τ})$

It addition, described average moisture absorption rateCan also be measured by experimental technique, it is assumed that described heat to be measured The quality of hygroscopic agent coated on matter weak coupling transmission heat exchanger is m, and the method that average moisture absorption rate curve is set up is as follows, as Shown in Fig. 2:

1, according to required evaporating temperature Te and condensation temperature Tc, respectively by the first thermal source 1 and the water outlet of Secondary Heat Source 2 Temperature is set to Te and Tc, the intake Qa used by setting measurement, inflow Qw, and sets the data acquisition of Temperature Humidity Sensor 6 Time interval is t0；

2, open the second valve 4, the hot water that temperature is Tc is passed through in heat exchanger to be measured, continue about 10 minutes；

3, close the second valve 4, open the first valve 3, the cold water that temperature is Te is passed through in heat exchanger to be measured, now treats Survey heat exchanger and be used as vaporizer, the record temperature sensor 5 of heat exchanger both sides and reading Ti, n and the di of humidity sensor 6, n, To, n and do, n, and record this process duration τ₁；

4, close the first valve 3, open the second valve 4, the hot water that temperature is Tc is passed through in heat exchanger to be measured, now treats Survey heat exchanger and be used as condenser, the record temperature sensor 5 of heat exchanger both sides and reading Ti, n and the di of humidity sensor 6, n, To, n and do, n, and record process duration τ₂；

5, it is repeated in process 3 and process 4, measures at least 3 circulations；

6, according to following formula calculating heat exchanger to be measured as the time equal moisture absorption rate of unit mass hygroscopic agent during vaporizer,

${\stackrel{\‾}{w}}_n=\frac{\underset{j=1}{\overset{n}{\Σ}}{\mathrm{\ρ}}_a\×Q_a\×({\mathrm{di}}_j-{\mathrm{do}}_j)\×t_0}{m\×n\×t_0}$

Wherein ρ_aRepresent air intake density, Q_aRepresent intake, (di_j-do_j) represent jth heat exchanger both sides humidity sensor The difference of device reading, m represents the gross mass of hygroscopic agent coated on heat exchanger, and n represents positive integer, t₀Represent epidemic disaster sensing The data collection interval of device.ρ in formula_aUnit time kg/m³,Q_aUnit time m³The unit of/s, do and di is that kg/kg does Air, t₀Unit is the second (s), and the unit of m is kg.Calculate respectively when n-th is measuredThus obtain τ=n × t₀In time The time equal moisture absorption rate of unit mass hygroscopic agentBy obtained each groupRepresent in coordinate diagram, can be formed Average moisture absorption rate curve as shown in Figure 1.

One of humiture weak rigidity control strategy of the present invention is characterised by: when the sensible heat load of air conditioner load increases Add and time latent heat load is constant, the constant persistent period (C → B mistake in such as Fig. 1 having only to reduce moisture absorption process of evaporating temperature Journey)；When sensible heat load is constant, when latent heat load increases, need first to reduce evaporating temperature and meet the requirement of wind pushing temperature, then root According to blasting humidity requirement, under new evaporating temperature, select (A → C the mistake in such as Fig. 1 of corresponding moisture absorption process persistent period Journey)；When sensible heat load reduces, when latent heat load also reduces, need first to improve evaporating temperature and meet the requirement of wind pushing temperature, then According to blasting humidity requirement, under new evaporating temperature, select (B → A the mistake in such as Fig. 1 of corresponding moisture absorption process persistent period Journey).

Above the specific embodiment of the present invention is described.It is to be appreciated that the invention is not limited in above-mentioned Particular implementation, those skilled in the art can make a variety of changes within the scope of the claims or revise, this not shadow Ring the flesh and blood of the present invention.In the case of not conflicting, the feature in embodiments herein and embodiment can any phase Combination mutually.

Claims (8)

1. an air conditioning system humiture weak rigidity control method, it is characterised in that comprise the steps:

Step 1, the evaporating temperature of regulation heat exchanger or condensation temperature are to realize the control to wind pushing temperature；

Step 2, the moisture absorption of regulation heat exchanger or the persistent period of moisture releasing are to realize the control to blasting humidity.

Air conditioning system humiture weak rigidity control method the most according to claim 1, it is characterised in that use ε-NTU method Determine evaporating temperature or condensation temperature T_evap, evaporating temperature or condensation temperature T_evapMeet:

T_out=T_in-(T_in-T_evap)(1-e^-NTU)

Wherein, T_outFor wind pushing temperature, T_inFor heat exchanger inlet temperature, T_evapFor evaporation or condensation temperature, NTU is that heat exchanger passes Hot cell number.

Air conditioning system humiture weak rigidity control method the most according to claim 2, it is characterised in that heat exchanger heat transfer list Unit number NTU meets:

Wherein, G_aFor the mass flow of handled air, C_p,aFor the specific heat capacity of handled air, h is that air side sensible heat convection current is changed Hot coefficient, A is air side heat exchange area.

Air conditioning system humiture weak rigidity control method the most according to claim 1, it is characterised in that step 2 includes:

Step 2.1, equal moisture absorption rate when setting upAnd the curve linear relationship between the persistent period τ of moisture absorption or moisture releasing；

Step 2.2, equal moisture absorption rate when determining

Step 2.3, determines blasting humidity.

Air conditioning system humiture weak rigidity control method the most according to claim 4, it is characterised in that in step 2.1, single The time equal moisture absorption rate of position quality hygroscopic agentMeet:

Wherein, ρ_aRepresent air intake density, Q_aRepresent intake, (di_j-do_j) represent that the humidity sensor of jth heat exchanger both sides is read The difference of number, m represents the gross mass of hygroscopic agent coated on heat exchanger, and n represents positive integer, t₀Represent temperature and relative humidity Data collection interval；

The persistent period τ of moisture absorption or moisture releasing meets:

τ=n × t₀。

Air conditioning system humiture weak rigidity control method the most according to claim 4, it is characterised in that step 2.2, determines Time equal moisture absorption rateMeet:

Wherein, Δ w_tThe representation unit quality hygroscopic agent total hygroscopic capacity in the persistent period τ of moisture absorption or moisture releasing, τ represent moisture absorption or The persistent period of moisture releasing.

Air conditioning system humiture weak rigidity control method the most according to claim 6, it is characterised in that in step 2.2, single The position quality hygroscopic agent total hygroscopic capacity Δ w in the persistent period τ of moisture absorption or moisture releasing_tMeet:

Wherein, w1 represents that, under evaporating state, unit mass hygroscopic agent reaches water capacity during saturated moisture absorption；W2 represents in condensation Under state, unit mass hygroscopic agent reaches water capacity during saturated moisture absorption；K represents moisture absorption rate constant.

Air conditioning system humiture weak rigidity control method the most according to claim 4, it is characterised in that in step 2.3, root According to time equal moisture absorption rate determine blasting humidity d_ao, blasting humidity d_aoMeet:

Wherein, G_aRepresent the air quantity by vaporizer；M represents the gross mass of hygroscopic agent coated on heat exchanger；d_aiRepresent and steam Send out the water capacity of device inlet air.