CN105650388B - The variable exchange device of cross shunt regulating four of fire and smoke exhaust type and anti-laying dust processing method - Google Patents
The variable exchange device of cross shunt regulating four of fire and smoke exhaust type and anti-laying dust processing method Download PDFInfo
- Publication number
- CN105650388B CN105650388B CN201511018966.9A CN201511018966A CN105650388B CN 105650388 B CN105650388 B CN 105650388B CN 201511018966 A CN201511018966 A CN 201511018966A CN 105650388 B CN105650388 B CN 105650388B
- Authority
- CN
- China
- Prior art keywords
- mrow
- particle concentration
- dust particle
- msub
- concentration area
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L41/00—Branching pipes; Joining pipes to walls
- F16L41/02—Branch units, e.g. made in one piece, welded, riveted
- F16L41/021—T- or cross-pieces
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L41/00—Branching pipes; Joining pipes to walls
- F16L41/02—Branch units, e.g. made in one piece, welded, riveted
- F16L41/03—Branch units, e.g. made in one piece, welded, riveted comprising junction pieces for four or more pipe members
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
- F16L55/24—Preventing accumulation of dirt or other matter in the pipes, e.g. by traps, by strainers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
- F24F13/00—Details common to, or for air-conditioning, air-humidification, ventilation or use of air currents for screening
-
- G—PHYSICS
- G16—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
- G16Z—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS, NOT OTHERWISE PROVIDED FOR
- G16Z99/00—Subject matter not provided for in other main groups of this subclass
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Prevention Of Fouling (AREA)
Abstract
The invention discloses a kind of variable exchange device of cross shunt regulating four of fire and smoke exhaust type and anti-laying dust processing method, the variable exchange device of cross shunt regulating four includes lower shoe, upper plate, side, the lower shoe are divided into high dust particle concentration area, middle dust particle concentration area and low dust particle concentration area；The high dust particle concentration area and middle dust particle concentration area use the anti-laying dust material of different roughness heights respectively.This cross shunt regulating four-way uses different roughness height purity materials at the position of different laying dust concentration, deposition of the suspended particulate substance at cross shunt regulating four-way can effectively be reduced, high-abrasive material usage amount is saved simultaneously, reduces the cost of cross shunt regulating four-way.
Description
Technical field
The invention belongs to industrial ventilation field, and in particular to a kind of variable exchange device of cross shunt regulating four and variable cross
The anti-laying dust processing method of the exchange device of shunt regulating four, particularly a kind of variable exchange device of cross shunt regulating four of fire and smoke exhaust type are prevented
Laying dust processing method.
Background technology
When outdoor air is handled through air-conditioner set in supply air system, because most of coarse-fine effect screen packs are only capable of filter 23 um
Suspended particulate substance above, its fine particle is then directly entered airduct with the wind, and the actual roughness height of airduct inner surface is much
Higher than the size of fine particle, therefore, these fine particulate matters produce with air and the mutual collision friction of airduct inwall
Electrostatic Absorption is cumulative, and so as to cause the roughness height of airduct inwall increasing, dust adhesion accelerates, so all the year round
Month after month form thicker laying dust.And all suspended particulate substances of exhaust system enter in pipeline with air-flow, laying dust is more serious.Especially
It is at the local resistance components such as the cross shunt regulating four-way of airduct, and air and suspended particulate substance and tube wall around are touched
It more acutely, is the position that laying dust abrasion is easiest in distributing system to hit.On the other hand, when fire occurs, flue dust enters with air-flow
Enter air channel, at the local resistance components such as air channel cross shunt regulating four-way deposit, obstruction air channel be unfavorable for flue gas discharge and
The elimination of fire.The harm that laying dust is brought mainly has three a variety of：1st, breed bacteria, disease is infected：Due in the ventilating duct of air channel
Dust, which can be deposited gradually, grows germ, gradually becomes the pollution sources of room air；2nd, flowed in air channel can be due to viscosity for air
And the relative motion of fluid produces internal friction, air flows in air channel will overcome this resistance and expend energy 3, fire hair
When raw, obstruction air channel is unfavorable for the discharge of flue gas and the elimination of fire.
It is reported that currently used cross shunt regulating four-way has no the measure of any anti-dust deposit.In order to prevent hanging
Deposition of the floating particles thing in pipeline cross shunt regulating four-way etc. easily at laying dust, simple thinking are to use roughness height as far as possible
Low clean tubing makes airduct cross shunt regulating four-way.But under actual conditions, not airduct cross shunt regulating four-way institute
There is all easy laying dust in position, that is to say, that some positions in some faces or same face for being not easy laying dust are not easy laying dust, using system
The method that one change airduct material changes clean tubing into will necessarily cause to expend unnecessary material in the part for being not easy laying dust, cause
The raising of whole airduct cross shunt regulating four-way cost.
The content of the invention
The defects of for existing cross shunt regulating four-way, can it is an object of the present invention to provide a kind of fire and smoke exhaust type
Become the exchange device of cross shunt regulating four, this cross shunt regulating four-way is at the position of different laying dust concentration using different coarse height
Purity material is spent, can effectively reduce deposition of the suspended particulate substance at cross shunt regulating four-way, while save high-abrasive material
Usage amount, reduce the cost of cross shunt regulating four-way.
To realize above-mentioned technical assignment, the present invention is achieved using following technical proposals：
A kind of variable exchange device of cross shunt regulating four of fire and smoke exhaust type, including upper plate, lower shoe and side, under described
Bottom plate is divided into high dust particle concentration area, middle dust particle concentration area and low dust particle concentration area；The high dust particle concentration area and middle grit
Concentration area uses the anti-laying dust material of different roughness heights respectively.
Further, the anti-laying dust material that the high dust particle concentration area uses is stainless steel cleaning tubing.
Further, the roughness height that anti-laying dust material is calculated using following formula：
In formula, HhThe roughness height of the stainless steel cleaning tubing used for high dust particle concentration area, mm；K is that bend pipe equivalent is thick
Rough height, mm；αmax-hFor the maximum dust particle concentration value of lower shoe；αh-mTo divide high dust particle concentration area and middle dust particle concentration area
Dust particle concentration threshold value；α is the dust particle concentration value at high dust particle concentration area or middle dust particle concentration area arbitrfary point；γ1It is dense for high grit
The roughness height constant coefficient in Du Li areas, γ is taken when INT functional values are 11=0.5, take γ when INT functional values are not 11=
1；INT is to round a numerical value as the function of immediate integer downwards.
Further, the anti-laying dust material that the middle dust particle concentration area uses is galvanized sheet metal.
Further, the roughness height of anti-laying dust material is calculated using following formula：
In formula, HmThe roughness height of galvanized sheet metal, mm are used for middle dust particle concentration area；K is bend pipe equivalent roughness height,
mm；αh-mTo divide the dust particle concentration threshold value in high dust particle concentration area and middle dust particle concentration area；αm-lFor dust particle concentration area in division and
The dust particle concentration threshold value in low dust particle concentration area；α is the dust particle concentration value at high dust particle concentration area or middle dust particle concentration area arbitrfary point；
γ2For middle dust particle concentration area roughness height constant coefficient, γ is taken when INT functional values are 12=0.5, when INT functional values are not 1
When take γ2=1；INT is to round a numerical value as the function of immediate integer downwards.
It is a further object of the invention to provide a kind of anti-laying dust processing method to cross shunt regulating four-way, bag
Include following steps：
Step 1：The continuity equation of air and the two phase flow of grit mixed flow is solved for cross shunt regulating four-way
With N-S equation of momentum partial differential equations, cross shunt regulating four-way stable state turbulent closure scheme thing velocity field U (x, y, z) is determined；
Step 2：The cross shunt regulating four-way stable state turbulent-velocity field U (x, y, z) obtained according to step 1, calculating is tried to achieve
The sliding velocity v of gritdr,p；
Step 3：The cross shunt regulating four-way stable state turbulent-velocity field U (x, y, z) and step 2 obtained according to step 1 is asked
The sliding velocity v of the grit of solutiondr,p, the grit volume components fractional equation shown in formula 2 is substituted into, single order lattice windward are carried out to formula 2
Formula discretization, and using Gauss-Saden, your iteration is solved, and obtains the volumetric concentration α of the i.e. grit of the second phasep(x, y, z), from
And obtain the dust particle concentration scope of lower shoe；
In formula, ρpFor density of dust, m3/kg；T is the time, s；vdr,pFor the sliding velocity of grit, m/s；ΔmqFor quality
Flow, kg/s.
Step 4：The dust particle concentration scope of the lower shoe obtained according to step 3, the division that lower shoe is calculated respectively are high
Dust particle concentration area and the threshold alpha in middle dust particle concentration areah-m；Dust particle concentration area and low dirt in the division of lower shoe is calculated simultaneously
The threshold alpha in grain concentration aream-l；By αh-mCorresponding curve is bent as senior middle school's dust particle concentration area envelope of lower shoe on lower shoe
Line；By αm-lZhong Di dust particle concentration area envelope curve of the corresponding curve as lower shoe on lower shoe；
Step 5：Zhong Di dust particle concentrations area envelope curve on the lower shoe that step 4 obtains, senior middle school's dust particle concentration respectively
Multiple discrete points are taken on area's envelope curve, and obtain the coordinate value of these discrete points；The low dust particle concentration area envelope curve of centering, height
The coordinate value of discrete point on middle dust particle concentration area envelope curve is fitted, and is obtained original fit curve equation, is then used
General Global Optimization Method is handled original fit curve equation, obtains Zhong Di dust particle concentrations area envelope curve, senior middle school's grit
Fit curve equation corresponding to concentration area envelope curve；
Step 6：Step 5 is obtained into point of the every fit curve equation as lower shoe Shang Ge dust particle concentrations area of lower shoe
Boundary line, obtain the high dust particle concentration area, middle dust particle concentration area and low dust particle concentration area of lower shoe.
Step 7：The high dust particle concentration area for the lower shoe that step 6 obtains uses stainless steel cleaning tubing, middle dust particle concentration area
Use galvanized sheet metal；Calculate the roughness height of the anti-laying dust material in high dust particle concentration area and middle dust particle concentration area；According to
The roughness height of anti-laying dust material is polished to the respective regions of anti-laying dust material.
Further, the sliding velocity v for trying to achieve grit is calculated using formula 1dr,p；
In formula, vdr,pFor the sliding velocity of grit, m/s ρpFor density of dust, m3/kg；ρmFor mixture density, m3/kg；dp
For grit diameter, m；fdragFor drag force function；vqFor air velocity, m/s, μqFor air force viscosity, m2/s。
Further, be utilized respectively that formula 3 is calculated lower shoe divides high dust particle concentration area and middle dust particle concentration area
Threshold alphah-m；The threshold alpha in dust particle concentration area and low dust particle concentration area in the division of lower shoe is calculated using formula 4 simultaneouslym-l；
In formula, αmax-h、αmin-lThe respectively maximum dust particle concentration value of lower shoe and minimum dust particle concentration value；ξ, ψ are region
Divide constant, 1≤ξ≤2,0 ＜ ψ≤1.
Further, in the step 7, the thick of the stainless steel cleaning tubing that high dust particle concentration area uses is determined according to formula 5
Rough height：
In formula, HhThe roughness height of the stainless steel cleaning tubing used for high dust particle concentration area, mm；K is that bend pipe equivalent is thick
Rough height, mm；αmax-hFor the maximum dust particle concentration value of lower shoe；αh-mTo divide high dust particle concentration area and middle dust particle concentration area
Dust particle concentration threshold value；α is the dust particle concentration value at high dust particle concentration area or middle dust particle concentration area arbitrfary point.γ1、γ2It is respectively high
Dust particle concentration power area, middle dust particle concentration area roughness height constant coefficient, γ is taken when INT functional values are 1 in formula 51, γ2=
0.5, take γ when INT functional values are not 1 in formula 51, γ2=1；INT is to round a numerical value to be immediate downwards
The function of integer.
Further, in the step 7, dust particle concentration area uses the roughness height of galvanized sheet metal in being determined according to formula 6：
In formula, HmThe roughness height of galvanized sheet metal, mm are used for middle dust particle concentration area；K is bend pipe equivalent roughness height,
mm；αh-mTo divide the dust particle concentration threshold value in high dust particle concentration area and middle dust particle concentration area；αm-lFor dust particle concentration area in division and
The dust particle concentration threshold value in low dust particle concentration area；α is the dust particle concentration value at high dust particle concentration area or middle dust particle concentration area arbitrfary point；
γ2For middle dust particle concentration area roughness height constant coefficient, γ is taken when INT functional values are 1 in formula 62=0.5, when in formula 6
INT functional values take γ when not being 12=1；INT is to round a numerical value as the function of immediate integer downwards.
The invention has the advantages that：
(1) method by solving two-phase flow partial differential equations, can be accurately positioned under cross shunt regulating four-way
The dust particle concentration size distribution of bottom plate, anti-laying dust processing is carried out with a definite target in view, can effectively reduce the shunting of airduct cross and adjust
Save the accumulation of grit inside four-way.
(2) high dust particle concentration area, middle dust particle concentration area and low dust particle concentration area lower shoe and extrados is respectively divided,
Anti- laying dust processing is carried out using different clean tubing in high dust particle concentration area and middle dust particle concentration area, can be targetedly and accurate
Really handling each needs position to be processed, improves anti-laying dust effect.
(3) Precise spraying, Er Qietong are carried out to the roughness height of high dust particle concentration area, the high-abrasive material in middle dust particle concentration area
One dust particle concentration region can select different roughness heights, and suitable roughness height can improve abrasion resistant effect.
Brief description of the drawings
Fig. 1 is existing cross shunt regulating four-way pipe schematic diagram；
Fig. 2 is that the anti-laying dust of lower shoe handles schematic diagram；
Fig. 3 is dust particle concentration field schematic diagram in existing cross shunt regulating four-way；
Fig. 4 is the high dust particle concentration of existing cross shunt regulating four-way lower shoe, middle dust particle concentration and low dust particle concentration area figure；
Fig. 5 is existing cross shunt regulating four-way (a) and the anti-laying dust lower shoe dirt of cross shunt regulating four-way of the present invention
Grain concentration distribution comparison diagram；Wherein, (a) is distributed for existing cross shunt regulating four-way lower shoe dust particle concentration；(b) it is the present invention
The distribution of cross shunt regulating four-way anti-laying dust lower shoe dust particle concentration.
Each label implication in figure：1- entrances；2- sides a；3- exports a；4- upper plates；5- sides b；6- sides c；7- is exported
c；8- sides d；9- sides e；10- exports c；11- flanges；12- sides f；13- lower shoes；The high dust particle concentration area of 14- lower shoes；
Dust particle concentration area in 15- lower shoes；The low dust particle concentration area of 16- lower shoes.
Embodiment
As shown in figure 1, the main body of the variable exchange device of cross shunt regulating four of fire and smoke exhaust type of the present invention is using common
Cross shunt regulating four-way, common cross shunt regulating four-way include：Entrance 1, side a2, outlet a3, upper plate 4, side
B5, side c6, outlet b7, side d8, side e9, outlet c10, flange 11, side f12, lower shoe 13.
In order to effectively prevent elbow grit from depositing, anti-laying dust is carried out to the lower shoe 4 of common cross shunt regulating four-way
Grain deposition processes.Other plate faces are not carried out with anti-laying dust grain because other plate face grit deposited concentration values are very low, in the present invention to sink
Product processing.Anti- laying dust grain deposition processes are specific as follows：
Lower shoe 13 is divided into high dust particle concentration area, middle dust particle concentration area and low dust particle concentration area.
Optionally, high dust particle concentration region uses stainless steel cleaning tubing, the roughness height of stainless steel cleaning tubing：
Optionally, middle dust particle concentration area uses galvanized sheet metal, the roughness height of galvanized sheet metal：
The present invention gives the anti-laying dust processing method to cross shunt regulating four-way, comprises the following steps：
Step 1：For common cross shunt regulating four-way, the continuous of air and the two phase flow of grit mixed flow is solved
Property equation and N-S equation of momentum partial differential equations, determine cross shunt regulating four-way stable state turbulent closure scheme thing velocity field U (x,
y,z)。
Optionally, the solution of above-mentioned continuity equation, N-S equation of momentum partial differential equations uses is solved based on pressure base
RNG k- ε turbulence models and combine simple algorithms and carry out.
Step 2：The cross shunt regulating four-way stable state turbulent-velocity field U (x, y, z) obtained according to step 1, formula 1 is substituted into,
Try to achieve the sliding velocity v of gritdr,p：
In formula, vdr,pFor the sliding velocity of grit, m/s ρpFor density of dust, m3/kg；ρmFor mixture density, m3/kg；dp
For grit diameter, m；fdragFor drag force function；vqFor air velocity, m/s, μqFor air force viscosity, m2/s。
Optionally, fdragSolved to obtain using Schiller and Naumann models.
Step 3：The cross shunt regulating four-way stable state turbulent-velocity field U (x, y, z) and step 2 obtained according to step 1 is asked
The sliding velocity v of the grit of solutiondr,p, the grit volume components fractional equation shown in formula 2 is substituted into, single order lattice windward are carried out to formula 2
Formula discretization, and using Gauss-Saden, your iteration is solved, and obtains the volumetric concentration α of the i.e. grit of the second phasep(x, y, z), from
And obtain the dust particle concentration scope of lower shoe；
In formula, ρpFor density of dust, m3/kg；T is the time, s；vdr,pFor the sliding velocity of grit, m/s；ΔmqFor quality
Flow, kg/s.
Step 4：The dust particle concentration scope of the lower shoe obtained according to step 3, it is utilized respectively formula 3 and obtains the division of lower shoe
High dust particle concentration area and the threshold alpha in middle dust particle concentration areah-m；Simultaneously using formula 4 obtain in the division of lower shoe dust particle concentration area and
The threshold alpha in low dust particle concentration aream-l；By αh-mCorresponding curve is as the high dust particle concentration area of lower shoe and middle dirt on lower shoe
Grain concentration distinguishes boundary line, i.e. senior middle school's dust particle concentration area envelope curve；By αm-lCorresponding curve is as lower shoe on lower shoe
Middle dust particle concentration area and low dust particle concentration distinguish boundary line, Ji Zhongdi dust particle concentrations area envelope curve；
In formula, αmax-h、αmin-lThe respectively maximum dust particle concentration value of lower shoe and minimum dust particle concentration value；ξ, ψ are region
Constant is divided, ξ/ψ is bigger, and the high dust particle concentration area scope of division is bigger, and low dust particle concentration area scope is smaller, it is necessary to anti-laying dust grain
The regional extent of deposition processes is bigger, and the effect of the anti-laying dust grain deposition of elbow is better, but anti-laying dust grain deposition processes material
Increase caused by the resistance of ducting can increase, expense also can accordingly increase.By verification experimental verification, 1≤ξ≤2,0 ＜ ψ≤1 are chosen
The resistance of ducting can be effectively reduced, realizes preferably anti-laying dust grain deposition effect.
Step 5：Zhong Di dust particle concentrations area envelope curve on the lower shoe that step 4 obtains, senior middle school's dust particle concentration respectively
More than enough (being no less than 200) discrete point is taken fully on area's envelope curve, and obtains the coordinate value of these discrete points；Using
On the low dust particle concentration area envelope curve of Levenberg-Marquardt algorithm centerings, senior middle school's dust particle concentration area envelope curve from
The coordinate value of scatterplot is fitted, and obtains original fit curve equation, then bent to original fitting using general Global Optimization Method
Line equation is handled, and it is bent to obtain fitting corresponding to Zhong Di dust particle concentrations area envelope curve, senior middle school's dust particle concentration area envelope curve
Line equation.
Numerical value change amplitude on envelope curve is can be seen that from the coordinate value of the point on envelope curve not knowing, parameter amount
It is more, using optimization calculating field in commonly use all kinds of iterative methods when, initial parameter value setting it is cumbersome and calculate be difficult to restrain, nothing
Method tries to achieve correct result, and inventor has carried out lot of experiments checking, and discovery uses the general overall situations of Levenberg-Marquardt+
Optimized algorithm, correct result can be tried to achieve since any random starting values, and then can be derived that each envelope curve is corresponding
High-precision, low residual error fit curve equation.
Step 6：Step 5 is obtained into point of the every fit curve equation as lower shoe Shang Ge dust particle concentrations area of lower shoe
Boundary line, obtain the high dust particle concentration area, middle dust particle concentration area and low dust particle concentration area of lower shoe.
Step 7：The high dust particle concentration area for the lower shoe that step 6 obtains uses stainless steel cleaning tubing, middle dust particle concentration area
Use galvanized sheet metal.It is specific as follows：
The roughness height for the stainless steel cleaning tubing that high dust particle concentration area uses determines that middle dust particle concentration area makes according to formula 5
Determined with the roughness height of galvanized sheet metal according to formula 6.From formula 5, formula 6, the anti-laying dust that is used in same dust particle concentration area
Grain deposition materials roughness height is different with dust particle concentration size, therefore, the different dust particle concentrations in same dust particle concentration area
The anti-laying dust grain deposition materials roughness height that section is calculated is one or more.
In formula, HhThe roughness height of the stainless steel cleaning tubing used for high dust particle concentration area, mm；HmFor middle dust particle concentration
Area uses the roughness height of galvanized sheet metal, mm；K is bend pipe equivalent roughness height, mm；αmax-hIt is dense for the maximum grit of lower shoe
Angle value；αh-mTo divide the dust particle concentration threshold value in high dust particle concentration area and middle dust particle concentration area；αm-lFor dust particle concentration area in division
With the dust particle concentration threshold value in low dust particle concentration area；α is the dust particle concentration at high dust particle concentration area or middle dust particle concentration area arbitrfary point
Value.γ1、γ2Respectively high dust particle concentration power area, middle dust particle concentration area roughness height constant coefficient, when INT functional values in formula 5,6
For 1 when take γ1, γ2=0.5, take γ when INT functional values are not 1 in formula 5,61, γ2=1；INT is by one
Numerical value is rounded downwards as the function of immediate integer.
According to the coarse height needed in each dust particle concentration area for the lower shoe being calculated using anti-laying dust grain deposition materials
Degree, is using stainless steel cleaning tubing in high dust particle concentration region, galvanized sheet metal is being used in middle dust particle concentration region, same
It is polished in dust particle concentration area according to the different roughness heights of anti-laying dust grain deposition materials, can further reduces the resistance of ducting
And Master Cost.
Embodiment 1
Specific embodiment of the invention given below is, it is necessary to which explanation is that the invention is not limited in implement in detail below
Example, all equivalents done on the basis of technical scheme each fall within protection scope of the present invention.
Defer to above-mentioned technical proposal, the section of the entrance and exit of the cross shunt regulating four-way in the present embodiment is
320mm × 250mm, upper plate, lower shoe, the material of all sides are steel plate, and roughness height is K=0.15mm, in elbow
The straight length of 2m length is terminated with before entrance, the straight length of 2m length is terminated with behind outlet.According to《Civil buildings heating ventilator and air
Adjusted design specification》Middle airduct main leg wind speed is 5~6.5m/s, and maximum is no more than 8m/s requirement, entrance front end straight length
Inlet velocity is taken as 6m/s.
Anti- laying dust processing is carried out to above-mentioned cross shunt regulating four-way using following steps：
Step 1：For cross shunt regulating four-way, using the RNG k- ε turbulence models solved based on pressure base and combine
The continuity equation and N-S equation of momentum partial differential equation of simple Algorithm for Solving air and the two phase flow of grit mixed flow
Group, determine elbow stable state turbulent closure scheme thing velocity field U (x, y, z).
Step 2：The cross shunt regulating four-way stable state turbulent-velocity field U (x, y, z) obtained according to step 1, formula 1 is substituted into,
Try to achieve the sliding velocity v of gritdr,p。
Step 3：The cross shunt regulating four-way stable state turbulent-velocity field U (x, y, z) obtained according to step 1 and step 2 institute
The sliding velocity v of solutiondr,p, substitute into formula 2 shown in grit volume components fractional equation, to formula 2 carry out single order upstreame scheme from
Dispersion, and using Gauss-Saden, your iteration is solved, and obtains the second phase grit i.e. volumetric concentration α of gritp(x, y, z), from
And obtain the dust particle concentration scope of lower shoe.
Step 4：α=β=1 is taken, the threshold for dividing high dust particle concentration area and middle dust particle concentration area of lower shoe is obtained using formula 3
Value αh-mFor：0.0126；The threshold alpha in dust particle concentration area and low dust particle concentration area in the division of lower shoe is obtained using formula 4m-lRespectively
For 0.011；By αh-mCorresponding curve distinguishes boundary as the high dust particle concentration area of lower shoe and middle dust particle concentration on lower shoe
Line, i.e. senior middle school's dust particle concentration area envelope curve；By αm-lMiddle dust particle concentration area of the corresponding curve as lower shoe on lower shoe
Boundary line, Ji Zhongdi dust particle concentrations area envelope curve are distinguished with low dust particle concentration.
Step 5：Zhong Di dust particle concentrations area envelope curve on the lower shoe that step 4 obtains, senior middle school's dust particle concentration respectively
200 discrete points are taken on area's envelope curve, and obtain the coordinate value of these discrete points；Calculated using Levenberg-Marquardt
The low dust particle concentration area envelope curve of method centering, the coordinate value of discrete point on senior middle school's dust particle concentration area envelope curve are fitted,
Obtain original fit curve equation；Then the intelligence independent of initial value is carried out to original fit curve equation with general Global Optimization Method
It can optimize, obtain Zhong Di dust particle concentration area envelope curve of the coefficient correlation more than 0.99, senior middle school's dust particle concentration area envelope curve pair
The fit curve equation answered.
It is bent to obtain fitting corresponding to lower shoe Shang Zhongdi dust particle concentrations area envelope curve, senior middle school's dust particle concentration area envelope curve
Line equation, is shown in Table 1.The high dust particle concentration region envelope curve equation of lower shoe is 1, middle dust particle concentration region envelope curve side
Journey is 2.
Fit curve equation corresponding to the envelope curve of table 1
(x*And y*For dimensionless coordinate, whereinR is elbow radius)
Step 6：Step 5 is obtained into point of the every fit curve equation as lower shoe Shang Ge dust particle concentrations area of lower shoe
Boundary line, obtain the high dust particle concentration area, middle dust particle concentration area and low dust particle concentration area of lower shoe.
Step 7：Stainless steel cleaning tubing is used in the high dust particle concentration area for the lower shoe that step 6 obtains, it is dense in middle grit
Degree area uses galvanized sheet metal.It is specific as follows：
According to formula 5, anti-laying dust grain deposition materials roughness height in the high dust particle concentration area of lower shoe is calculated respectively and (is shown in Table
2)；It can be seen that the roughness height that the different sections in the high dust particle concentration power area of lower shoe obtain is different；
It is divided into two kinds of coarse height according to the anti-laying dust grain deposition materials that the high dust particle concentration power area of lower shoe uses are calculated
Degree polishing.
According to formula 6, anti-laying dust grain deposition materials roughness height in the middle dust particle concentration power area of lower shoe is calculated respectively；According to
Anti- laying dust grain deposition materials roughness height in noise regions in the lower shoe being calculated, anti-laying dust grain sinks in noise regions in lower shoe
Product material is divided into three kinds of roughness height polishings.Anti- laying dust grain deposition materials and roughness height value such as table 2.
The anti-laying dust grain deposition materials in each dust particle concentration area of table 2 and roughness height
Such as：The roughness height H of the high dust particle concentration area stainless steel cleaning tubing polishing of lower shoehAsk for it is as follows：
The high dust particle concentration region of lower shoe for 0.0126-0.0144, now αh-m=0.0126 (αh-mTo divide high dirt
Grain concentration area and the threshold value in middle dust particle concentration area), αmax-h=0.0144 (αmax-hFor the maximum dust particle concentration value of lower shoe).α's
Span is exactly 0.0126-0.0144.K is dovetail threeway equivalent roughness height, takes K=0.15mm.
The first step：The substitution formula 5 of α=0.0126 is taken to understand first：
Rounded downwards as the function of immediate integer because INT is a numerical value,
So INT [1.4285]=1,
Because during INT [1.4285]=1, γ is taken1=0.5
So Hh=γ1The ≈ 0.08 of × K=0.5 × 0.15.
Second step：Similarly：Take α=0.0126-0.0132 to substitute into formula 5 successively to understand：
Hh=γ1The ≈ 0.08 of × K=0.5 × 0.15.
3rd step：The substitution formula 5 of α=0.0132 is taken to understand：
Rounded downwards as the function of immediate integer because INT is a numerical value,
So INT [2.0]=2,
Because INT [2.0]=2 ≠ 1, takes γ1=1.0
So Hh=γ1The ≈ 0.08 of × K × 0.5=1 × 0.15 × 0.5.
4th step：The substitution formula 5 of α=0.0143 is taken to understand：
Between section (0.0132-0.0143), Hh=γ1The ≈ 0.08 of × K × 0.5=1 × 0.15 × 0.5
5th step：The substitution formula 5 of α=0.0144 is taken to understand：
Rounded downwards as the function of immediate integer because INT is a numerical value,
So INT [3.061]=3,
Because INT [3.061]=3 ≠ 1, takes γ1=1.0
So Hh=γ1× K × 0.33=1 × 0.15 × 3-1=0.05
So calculate：Hh0.0126-0.0143 in the high dust particle concentration region (0.0126-0.0144) of lower shoe
During region, Hh=0.08mm.
Hh0.0143-0.0144 in the high dust particle concentration region (0.0126-0.0144) of lower shoe
During region, Hh=0.05mm.
So the anti-laying dust grain deposition materials for calculating the different dust particle concentration sections polishing in same dust particle concentration area are thick
Rough height can be different.
The dirt of the clean dovetail threeway of industrial ventilation after the above method of the present invention carries out anti-laying dust grain deposition processes
Grain distribution of concentration such as Fig. 5.Through comparing, industrial ventilation of the invention is obvious with the anti-laying dust grain deposition effect of dovetail threeway, most
The dust particle concentration in high dust particle concentration region is reduced to 0.00648 by height by 0.0144,55% is reduced, by middle dust particle concentration region
Dust particle concentration be reduced to 0.00517 by 0.0126, reduce 59%.At the same time, the method for roughening height effectively reduces
The polishing quantities and its caused resistance of ducting of anti-laying dust grain deposition materials, reduce initial cost cost.
Claims (4)
1. a kind of anti-laying dust processing method to cross shunt regulating four-way, it is characterised in that comprise the following steps：
Step 1：The continuity equation and N-S of air and the two phase flow of grit mixed flow are solved for cross shunt regulating four-way
Equation of momentum partial differential equations, determine cross shunt regulating four-way stable state turbulent closure scheme thing velocity field U (x, y, z)；
Step 2：Grit is tried to achieve in the cross shunt regulating four-way stable state turbulent-velocity field U (x, y, z) obtained according to step 1, calculating
Sliding velocity vdr,p；
Step 3：What the cross shunt regulating four-way stable state turbulent-velocity field U (x, y, z) and step 2 obtained according to step 1 was solved
The sliding velocity v of gritdr,p, the grit volume components fractional equation shown in following formula is substituted into, single order upstreame scheme is carried out to following formula
Discretization, and using Gauss-Saden, your iteration is solved, and obtains the second phase i.e. dust particle concentration αp(x, y, z), so as to obtain down
The dust particle concentration scope of bottom plate；
<mrow>
<mfrac>
<mo>&part;</mo>
<mrow>
<mo>&part;</mo>
<mi>t</mi>
</mrow>
</mfrac>
<mrow>
<mo>(</mo>
<msub>
<mi>&alpha;</mi>
<mi>p</mi>
</msub>
<msub>
<mi>&rho;</mi>
<mi>p</mi>
</msub>
<mo>)</mo>
</mrow>
<mo>+</mo>
<mo>&dtri;</mo>
<mo>&CenterDot;</mo>
<mrow>
<mo>(</mo>
<msub>
<mi>&alpha;</mi>
<mi>p</mi>
</msub>
<msub>
<mi>&rho;</mi>
<mi>p</mi>
</msub>
<mi>U</mi>
<mo>)</mo>
</mrow>
<mo>=</mo>
<mo>-</mo>
<mo>&dtri;</mo>
<mo>&CenterDot;</mo>
<mrow>
<mo>(</mo>
<msub>
<mi>&alpha;</mi>
<mi>p</mi>
</msub>
<msub>
<mi>&rho;</mi>
<mi>p</mi>
</msub>
<msub>
<mi>v</mi>
<mrow>
<mi>d</mi>
<mi>r</mi>
<mo>,</mo>
<mi>p</mi>
</mrow>
</msub>
<mo>)</mo>
</mrow>
<mo>+</mo>
<munderover>
<mo>&Sigma;</mo>
<mrow>
<mi>q</mi>
<mo>=</mo>
<mn>1</mn>
</mrow>
<mi>n</mi>
</munderover>
<msub>
<mi>&Delta;m</mi>
<mi>q</mi>
</msub>
</mrow>
In formula, ρpFor density of dust, m3/kg；T is the time, s；vdr,pFor the sliding velocity of grit, m/s；ΔmqFor mass flow,
kg/s；
Step 4：The dust particle concentration scope of the lower shoe obtained according to step 3, the high grit of division of lower shoe is calculated respectively
Concentration area and the threshold alpha in middle dust particle concentration areah-m；It is dense that dust particle concentration area and low grit in the division of lower shoe is calculated simultaneously
Spend the threshold alpha in aream-l；By αh-mSenior middle school dust particle concentration area envelope curve of the corresponding curve as lower shoe on lower shoe；Will
αm-lZhong Di dust particle concentration area envelope curve of the corresponding curve as lower shoe on lower shoe；
Step 5：Zhong Di dust particle concentrations area envelope curve on the lower shoe that step 4 obtains, dust particle concentration area of senior middle school bag respectively
Multiple discrete points are taken on network curve, and obtain the coordinate value of these discrete points；The low dust particle concentration area envelope curve of centering, senior middle school's dirt
The coordinate value of discrete point on grain concentration area envelope curve is fitted, and original fit curve equation is obtained, then using general
Global Optimization Method is handled original fit curve equation, obtains Zhong Di dust particle concentrations area envelope curve, senior middle school's dust particle concentration
Fit curve equation corresponding to area's envelope curve；
Step 6：Step 5 is obtained into boundary of the every fit curve equation as lower shoe Shang Ge dust particle concentrations area of lower shoe
Line, obtain the high dust particle concentration area, middle dust particle concentration area and low dust particle concentration area of lower shoe；
Step 7：Stainless steel cleaning tubing is used in the high dust particle concentration area for the lower shoe that step 6 obtains, in middle dust particle concentration area
Using galvanized sheet metal；Calculate the roughness height for the anti-laying dust material that high dust particle concentration area and middle dust particle concentration area use；Root
The respective regions of anti-laying dust material are polished according to the roughness height of anti-laying dust material.
2. as claimed in claim 1 to the anti-laying dust processing method of cross shunt regulating four-way, it is characterised in that be utilized respectively
The threshold alpha for dividing high dust particle concentration area and middle dust particle concentration area of lower shoe is calculated in following formulah-m；
<mrow>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>h</mi>
<mo>-</mo>
<mi>m</mi>
</mrow>
</msub>
<mo>=</mo>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>max</mi>
<mo>-</mo>
<mi>h</mi>
</mrow>
</msub>
<mo>-</mo>
<mrow>
<mo>(</mo>
<mfrac>
<mrow>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>max</mi>
<mo>-</mo>
<mi>h</mi>
</mrow>
</msub>
<mo>-</mo>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>min</mi>
<mo>-</mo>
<mi>h</mi>
</mrow>
</msub>
</mrow>
<mn>3</mn>
</mfrac>
<mo>)</mo>
</mrow>
<mi>&xi;</mi>
<mo>,</mo>
<mn>1</mn>
<mo>&le;</mo>
<mi>&xi;</mi>
<mo>&le;</mo>
<mn>3</mn>
</mrow>
The threshold alpha in dust particle concentration area and low dust particle concentration area in the division of lower shoe is calculated using following formula simultaneouslym-l；
<mrow>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>m</mi>
<mo>-</mo>
<mi>l</mi>
</mrow>
</msub>
<mo>=</mo>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>min</mi>
<mo>-</mo>
<mi>l</mi>
</mrow>
</msub>
<mo>+</mo>
<mrow>
<mo>(</mo>
<mfrac>
<mrow>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>m</mi>
<mi>a</mi>
<mi>x</mi>
<mo>-</mo>
<mi>h</mi>
</mrow>
</msub>
<mo>-</mo>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>min</mi>
<mo>-</mo>
<mi>l</mi>
</mrow>
</msub>
</mrow>
<mn>3</mn>
</mfrac>
<mo>)</mo>
</mrow>
<mi>&psi;</mi>
<mo>,</mo>
<mn>0</mn>
<mo><</mo>
<mi>&psi;</mi>
<mo>&le;</mo>
<mn>1</mn>
</mrow>
In formula, αmax-h、αmin-lThe respectively maximum dust particle concentration value of lower shoe and minimum dust particle concentration value；ξ, ψ are region division
Constant.
3. as claimed in claim 1 to the anti-laying dust processing method of cross shunt regulating four-way, it is characterised in that the step
In 7, the roughness height of the stainless steel cleaning tubing of high dust particle concentration area use is determined according to following formula：
<mrow>
<msub>
<mi>H</mi>
<mi>h</mi>
</msub>
<mo>=</mo>
<msub>
<mi>&gamma;</mi>
<mn>1</mn>
</msub>
<mo>&times;</mo>
<mi>K</mi>
<mo>&times;</mo>
<msup>
<mrow>
<mo>{</mo>
<mi>I</mi>
<mi>N</mi>
<mi>T</mi>
<mo>&lsqb;</mo>
<mn>10</mn>
<mrow>
<mo>(</mo>
<mfrac>
<mi>&alpha;</mi>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>h</mi>
<mo>-</mo>
<mi>m</mi>
</mrow>
</msub>
</mfrac>
<mo>&times;</mo>
<mfrac>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>m</mi>
<mi>a</mi>
<mi>x</mi>
<mo>-</mo>
<mi>h</mi>
</mrow>
</msub>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>h</mi>
<mo>-</mo>
<mi>m</mi>
</mrow>
</msub>
</mfrac>
<mo>-</mo>
<mn>1</mn>
<mo>)</mo>
</mrow>
<mo>&rsqb;</mo>
<mo>}</mo>
</mrow>
<mrow>
<mo>-</mo>
<mn>1</mn>
</mrow>
</msup>
</mrow>
In formula, HhThe roughness height of the stainless steel cleaning tubing used for high dust particle concentration area, mm；K is the coarse height of bend pipe equivalent
Degree, mm；αmax-hFor the maximum dust particle concentration value of lower shoe；αh-mTo divide the grit in high dust particle concentration area and middle dust particle concentration area
Concentration threshold；α is the dust particle concentration value at high dust particle concentration area or middle dust particle concentration area arbitrfary point；γ1For high dust particle concentration area
Roughness height constant coefficient, γ is taken when INT functional values are 1 in above formula1=0.5, when INT functional values are not 1 in above formula
When take γ1=1；INT is to round a numerical value as the function of immediate integer downwards.
4. as claimed in claim 1 to the anti-laying dust processing method of cross shunt regulating four-way, it is characterised in that the step
In 7, dust particle concentration area uses the roughness height of galvanized sheet metal in being determined according to following formula：
<mrow>
<msub>
<mi>H</mi>
<mi>m</mi>
</msub>
<mo>=</mo>
<msub>
<mi>&gamma;</mi>
<mn>2</mn>
</msub>
<mo>&times;</mo>
<mi>K</mi>
<mo>&times;</mo>
<msup>
<mrow>
<mo>{</mo>
<mi>I</mi>
<mi>N</mi>
<mi>T</mi>
<mo>&lsqb;</mo>
<mn>10</mn>
<mrow>
<mo>(</mo>
<mfrac>
<mi>&alpha;</mi>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>m</mi>
<mo>-</mo>
<mi>l</mi>
</mrow>
</msub>
</mfrac>
<mo>&times;</mo>
<mfrac>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>h</mi>
<mo>-</mo>
<mi>m</mi>
</mrow>
</msub>
<msub>
<mi>&alpha;</mi>
<mrow>
<mi>m</mi>
<mo>-</mo>
<mi>l</mi>
</mrow>
</msub>
</mfrac>
<mo>)</mo>
</mrow>
<mo>-</mo>
<mn>1</mn>
<mo>&rsqb;</mo>
<mo>}</mo>
</mrow>
<mrow>
<mo>-</mo>
<mn>1</mn>
</mrow>
</msup>
</mrow>
In formula, HmThe roughness height of galvanized sheet metal, mm are used for middle dust particle concentration area；K is bend pipe equivalent roughness height, mm；
αh-mTo divide the dust particle concentration threshold value in high dust particle concentration area and middle dust particle concentration area；αm-lFor dust particle concentration area in division and low dirt
The dust particle concentration threshold value in grain concentration area；α is the dust particle concentration value at high dust particle concentration area or middle dust particle concentration area arbitrfary point；γ2
For middle dust particle concentration area roughness height constant coefficient, γ is taken when INT functional values are 1 in above formula2=0.5, when in above formula
INT functional values take γ when not being 12=1；INT is to round a numerical value as the function of immediate integer downwards.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201511018966.9A CN105650388B (en) | 2015-12-29 | 2015-12-29 | The variable exchange device of cross shunt regulating four of fire and smoke exhaust type and anti-laying dust processing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201511018966.9A CN105650388B (en) | 2015-12-29 | 2015-12-29 | The variable exchange device of cross shunt regulating four of fire and smoke exhaust type and anti-laying dust processing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105650388A CN105650388A (en) | 2016-06-08 |
| CN105650388B true CN105650388B (en) | 2018-02-06 |
Family
ID=56478371
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201511018966.9A Active CN105650388B (en) | 2015-12-29 | 2015-12-29 | The variable exchange device of cross shunt regulating four of fire and smoke exhaust type and anti-laying dust processing method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105650388B (en) |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1287046A (en) * | 1970-09-03 | 1972-08-31 | Howorth Air Conditioning Ltd F | Improvements in air distribution ducts or pipes |
| JP3128686B2 (en) * | 1995-06-20 | 2001-01-29 | 新菱冷熱工業株式会社 | Duct joint capable of crossing |
| CN2779292Y (en) * | 2005-03-25 | 2006-05-10 | 邵国发 | Strong power air duct for ventilating dust-removing energy-saving |
| CN202452649U (en) * | 2011-12-13 | 2012-09-26 | 中山市宇恒电器有限公司 | Static dedusting sterilizing filtering device |
| CN102937327A (en) * | 2012-11-26 | 2013-02-20 | 攀枝花钢城集团瑞通制冷设备有限公司 | Fresh air filtering dusting machine |
| CN103604007B (en) * | 2013-11-26 | 2016-02-17 | 中国建筑第八工程局有限公司 | A kind of method of construction of composite air duct |
-
2015
- 2015-12-29 CN CN201511018966.9A patent/CN105650388B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN105650388A (en) | 2016-06-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN203075794U (en) | Spraying type haze-dust air purifier | |
| CN104596769A (en) | Real thrust measuring and calculating method for test run of aero-engine on indoor test bed | |
| CN105650388B (en) | The variable exchange device of cross shunt regulating four of fire and smoke exhaust type and anti-laying dust processing method | |
| CN205517023U (en) | Anticorrosive wet dust collector | |
| Jing et al. | An anti-channeling flue tee with cycloidal guide vanes based on variational calculus | |
| CN105701067B (en) | Smoke prevention type lower resistance industrial ventilation rectangle flaring resistance component and anti-dust accumulation method | |
| CN105673978B (en) | A kind of anti-dust accumulation processing method of the anti-dust accumulation elbow of 90 ° of rectangles and elbow | |
| CN105570592B (en) | A kind of anti-laying dust processing method of U-shaped pipe elbow | |
| CN105546798B (en) | Anti- appositional pattern ventilation Pneumatic conveying pipeline dovetail threeway and anti-dust accumulation processing method | |
| Lee | A computational flow analysis for choosing the diameter and position of an air duct in a working face | |
| CN107062378B (en) | Energy-saving dust removal device for near-wall heat source | |
| Kim et al. | Collection efficiency of round-nozzle impactors with horizontal annular inlet | |
| CN108049667B (en) | Wind-force formula dust removal environmental protection is from thermoregulation factory building sunken | |
| CN104588214B (en) | Electric cleaner rate of discharge acquisition methods and device, except dust quantity acquisition methods and device | |
| CN207591507U (en) | A kind of water mist dust-removing system | |
| CN106809898A (en) | Carbon dioxide cleaner and the carbon dioxide cleaner except carbon control method and device | |
| CN106422614B (en) | A kind of filter cartridge dust remover of balanced ventilation | |
| Zhang et al. | Hydraulic performance and deposition enhancement of ultrafine particles for in-duct twisted tapes under stationary and rotating conditions | |
| CN114440385A (en) | Air purifier rotating speed control method | |
| CN104368193B (en) | There is the smoke gas collecting apparatus of the tube bank of many misarrangements row water conservancy diversion and triangle dilatation cover | |
| CN105485461B (en) | A kind of wear resistant processing method of anti-wear S bend pipe road elbow and elbow | |
| CN103018005A (en) | Method for reducing erosive abrasion of solid particles on wall surface | |
| CN105653780B (en) | A kind of wear resistant processing method of U-shaped pipe elbow | |
| CN205393144U (en) | Sand -blast shop dust collector | |
| CN204902179U (en) | Drainage structure of floor air conditioner |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |