CN115048839B - Device and method for testing outlet area of pressure relief valve - Google Patents
Device and method for testing outlet area of pressure relief valve Download PDFInfo
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Abstract
The invention relates to a device and a method for testing the outlet area of a pressure relief valve. The test method comprises the steps of constructing a connected air supply device and a static pressure cavity to obtain different air volumes Q 1 The corresponding pressure value P 1 Fitting the pressure and the air quantity to obtain P 1 =f 1 (Q 1 ) The method comprises the steps of carrying out a first treatment on the surface of the Establishing a corresponding finite element model; will give the air quantity Q 2 Input into the model for calculation according to P 1 Calculating P in the model 2 The method comprises the steps of carrying out a first treatment on the surface of the Will Q 2 Carry over P 1 =f 1 (Q 1 ) To obtain theoretical pressure P 2,c When P 2 And P 2,c The difference of the pressure is smaller than the set error, the outlet area S and the pressure P of the output relief valve 2 The method comprises the steps of carrying out a first treatment on the surface of the Changing Q 2 Different P's can be obtained 2 The next corresponding S. The invention also provides a testing device based on the testing method, which comprises an air supply device and a static pressure cavity, wherein a pressure detection point is arranged in the static pressure cavity. The invention can accurately measure the outlet area of the automobile exhaust pressure relief valve under different static pressure conditions.
Description
Technical Field
The invention relates to the technical field of automobile air conditioner ventilation systems, in particular to a device and a method for testing the outlet area of a pressure relief valve.
Background
The air intake and exhaust performance of an automotive air conditioning ventilation system is directly related to the heating, cooling, system pressure loss and air volume of the whole ventilation system and the riding comfort of users. In general, automobile exhaust is composed of natural leakage generated by the air tightness of a vehicle body and active exhaust of a pressure release valve. However, as the requirements on driving noise become more stringent, the air tightness of the vehicle body becomes better, so that the proportion of natural leakage exhaust in the exhaust of the whole vehicle is further reduced. Therefore, the venting performance of the pressure relief valve is critical. Wherein, when the door is closed rapidly, the pressure in the car increases suddenly, if the exhaust performance is poor, the human ear can bear extremely high air pressure, thereby causing serious discomfort. In addition, when the air conditioner is turned on, if the exhaust performance is poor, the electric back door may not be closed due to excessive pressure in the vehicle. In the driving process, if the exhaust performance is poor, the pressure difference between the inside and the outside of the automobile is too large, and discomfort of human ears is also easily caused.
The root of the above problems is that in the early stages of automobile development, the prediction of exhaust performance is inaccurate. Because the pressure release valve is complex in structure, the valve plate of the pressure release valve can fluctuate up and down according to the exhaust air quantity, so that the pressure release valve is difficult to test or construct a real model for simulation. Therefore, the simulation analysis of the exhaust performance of the pressure relief valve is basically based on a series of simplifications of the pressure relief valve, namely, the mode of using the outlet area to equivalently exhaust the pressure relief valve is simulated. In the current simulation calculation, the area of the outlet of the pressure relief valve is always a fixed value and cannot be adjusted in real time along with the wind volume or static pressure change, but in practice, under different static pressures, the area of the outlet of the pressure relief valve is completely different, so that the defects of inaccurate measurement, large calculation error and low precision are caused.
Disclosure of Invention
The invention aims to provide a testing device and a testing method for the outlet area of a pressure relief valve, so as to accurately measure the outlet area of an automobile exhaust pressure relief valve under different static pressure conditions, thereby truly and effectively evaluating the exhaust performance of the pressure relief valve.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
the method for testing the outlet area of the pressure relief valve comprises the following steps:
s1, building a testing device, wherein the testing device comprises air supply equipment and a static pressure cavity which are connected, a pressure relief valve to be tested is embedded at an air outlet of the static pressure cavity, air flows into the static pressure cavity through the air supply equipment, the air is discharged from the pressure relief valve to be tested after being stabilized in the static pressure cavity, a pressure detection point is arranged in the static pressure cavity, and different air quantities Q are monitored and fed back through the pressure detection point 1 The corresponding pressure value P 1 Pressure P 1 And the air quantity Q 1 Fitting to obtain an equation:
P 1 =f 1 (Q 1 ) （Ⅰ）
Q 1 represents the air quantity, and the unit is m 3 /h，P 1 Pressure is expressed in Pa;
s2, establishing a corresponding finite element model in simulation software according to the established testing device, setting an air outlet of air supply equipment as an inlet boundary of the whole finite element model, setting a boundary type as a mass flow inlet, simplifying an outlet of a pressure release valve as a rectangular outlet, setting a boundary type as a pressure outlet, and setting boundary types of static pressure cavities as wall surfaces;
s3, giving the air quantity Q 2 After the conversion into mass flow, assigning the mass flow to an inlet boundary, performing initial calculation for the first time, iterating until the residual value is smaller than a set value, and calculating the pressure P at the same position in simulation software according to the position of a pressure detection point in the testing device 2 ；
S4, giving the air quantity Q 2 And then is carried into an equation (I), and a theoretical pressure value P is calculated 2,c =f 1 (Q 2 ) Judgment of P 2 And P 2,c Is a difference deltaP of (1) 2 If the absolute value of (2) is less than or equal to the set error value, if so, the outlet area S and the pressure P of the relief valve are output 2 ；
S5, changing the given air quantity Q 2 Repeating the steps S3-S4 to obtain different pressures P 2 The pressure P is set by the outlet area S of the corresponding relief valve 2 Fitting to the exit area S yields the equation:
S=f 2 (P 2 ) （Ⅱ）
P 2 expressed in Pa, S expressed in m, and the outlet area of the relief valve 2 。
According to the technical means, the ventilation equipment and the static pressure cavity are arranged, the air supply equipment controls the air quantity entering the static pressure cavity, so that the pressure in the static pressure cavity is changed, and then the outlet area of the automobile exhaust pressure relief valve under different static pressure conditions can be accurately calculated by combining simulation software, so that the exhaust performance of the pressure relief valve can be truly and effectively evaluated.
Preferably, in S4, if P 2 And P 2,c Is a difference deltaP of (1) 2 When the absolute value of (a) is larger than the set error value, the Z-direction height of the pressure outlet in the finite element model is directly adjusted in the next iterative calculation according to the difference value by utilizing the deformation and Field function custom function in the simulation software, namely the outlet area of the pressure relief valve is adjusted, and then the iteration is performed until the number of steps is set until the number of steps is P 2 And P 2,c Is a difference deltaP of (1) 2 The absolute value of (2) is smaller than or equal to the set error value, and then the outlet area S and the pressure P of the pressure relief valve at the moment are output 2 。
Preferably, the Z-direction height of the pressure outlet is adjusted by the amplitude of delta P 2 Proportional to the ratio.
Wherein, the adjustment value of the outlet area S of the pressure relief valve is equal to delta P 2 Correlation, deltaP 2 The larger the outlet area S, the larger the adjustment amplitude of ΔP 2 The smaller the outlet area S, the smaller the adjustment amplitude of the outlet area S, i.e. the adjustment amplitude of the Z-directional height of the pressure outlet and DeltaP 2 Proportional to DeltaP 2 The larger the Z-direction height H is, the larger the adjustment amplitude is, and the delta P is 2 The smaller the Z-direction height H adjustment amplitude is, the smaller the Z-direction height H adjustment amplitude is.
Preferably, the simulation software is starccm+ simulation software.
Among them, starccm+ is a new generation CFD solver developed by CD-adapt co corporation using the most advanced continuous media mechanics numerical technique (computational continuum mechanics algorithms). The method is carried with the latest grid generation technology created by CD-adapco, and can complete a series of operations required by complex shape data input, surface preparation, such as wrapping (functions of maintaining shape, simplifying geometry, automatic hole filling, preventing component contact, checking leakage and the like), surface grid reconstruction, automatic grid generation (including polyhedral grids, hexahedral core grids, dodecahedral core grids, tetrahedral grids) and the like.
Compared with the original tetrahedral mesh, the STAR-CCM+polyhedral mesh advocated by CD-adaptive co is capable of realizing about 3-10 times improvement of calculation performance under the condition of keeping the same calculation precision.
Preferably, the method for adjusting the Z-direction height of the pressure outlet is as follows:
newly building a shaping motion node in the motion node;
based on Morhper, setting the iteration step number of each 499 in the steady state calculation process, and then adjusting the physical position of the upper outline of the boundary of the pressure outlet according to the error range control logic to realize the stretching and compression of the pressure outlet in the Z direction;
based on Field function, when ΔP 2 When the absolute value of (a) is larger than the set error value, steady-state calculation is continuously performed, and logic judgment is performed every 499 iteration steps until deltaP is reached 2 The absolute value of (a) is smaller than the set error value.
Preferably, in S1, equation (I) is P 1 = a×Q 1 2 + b×Q 1 Wherein Q is 1 Represents the air quantity, and the unit is m 3 /h，P 1 Representing pressure, wherein the unit is Pa, and a and b are fitting coefficients;
in S5, equation (ii) is s=c×arctan (P 2 ) -d, wherein P 2 Expressed in Pa, S expressed in m, and the outlet area of the relief valve 2 And c and d are fitting coefficients.
Preferably, the air supply amount of the inlet boundary is 25m 3 /h~325m 3 The difference between the adjacent air quantity and the adjacent air quantity is not more than50 m 3 /h；
The boundary pressure of the pressure outlet is 1.01X10 5 Pa；
The error value was set to 0.5Pa.
Wherein, the air quantity Q is given for each inlet boundary 2 As close as possible to the air supply quantity Q given by the test device 1 Or given air quantity Q 2 The value of the air quantity Q is equal to that of the air quantity 1 。
The invention also provides a testing device for the outlet area of the pressure relief valve based on the testing method, which comprises air supply equipment and a static pressure cavity;
the static pressure cavity is a cuboid with a hollow inside, an air inlet is formed in one side face, an air outlet is formed in the side face adjacent to the side face with the air inlet, the air supply equipment is communicated with the air inlet through a ventilation pipe, the air outlet is used for placing a pressure relief valve to be tested, air entering the static pressure cavity is discharged from the pressure relief valve to be tested, and a pressure detection point is arranged on the lower side of the air outlet in the static pressure cavity.
Preferably, the air inlet is positioned on the left side surface or the right side surface and close to the top surface, and the air outlet is positioned on the front surface or the back surface and close to the bottom surface.
Preferably, the pressure detection point is located at the inner wall surface close to the front surface, and the ventilation pipe is a circular air pipe.
By arranging the pressure detection point at a position close to the front surface in the static pressure cavity, the air inlet flow is effectively avoided, and the measurement result of the pressure detection point is ensured to be static pressure; meanwhile, a section of circular transition pipe is arranged between the air supply equipment and the air inlet, so that the calculation result is effectively ensured to be closer to the real measurement result.
The invention has the beneficial effects that:
1) According to the method for testing the outlet area of the pressure relief valve, disclosed by the invention, the outlet area of the pressure relief valve under different static pressure conditions can be accurately and effectively calculated by constructing a simple testing device for simulating the air quantity and the pressure of the pressure relief valve and combining with STARCCM+simulation software, and the testing device does not need to be matched with the pressure relief valve with high precision, so that compared with the traditional outlet area measuring equipment, the testing method is simpler, the cost is lower, the testing period is shorter, the flow is less, and the practicability is stronger; meanwhile, the accuracy of a test result is effectively ensured by combining the test device with the STARCCM+ simulation software, and a finite element model of the test device built by the STARCCM+ simulation software can be directly matched with a whole vehicle model, so that the method is applied to the prediction and evaluation of the static pressure performance in the vehicle in the early and middle stages of the whole vehicle design, and the universality of the test method is improved;
2) According to the method for testing the outlet area of the pressure relief valve, in the steady state calculation process of STARCCM+simulation software, the automatic matching of the outlet area of the pressure relief valve is realized in a self-defined function mode, and the method has the advantages of high calculation efficiency and high popularization value, and has popularization and application values in the technical field of automobile air conditioning ventilation systems.
Drawings
FIG. 1 is a schematic diagram of a device for testing the outlet area of a pressure relief valve according to the present invention;
FIG. 2 is a flow chart of a method for testing the area of an outlet of a pressure relief valve according to the present invention;
fig. 3 is a flow chart of the adjustment of the outlet area of the relief valve in example 2.
Wherein, 1-air supply equipment; 2-static pressure cavity, 21-air inlet, 22-air outlet, 23-left side face and 24-front face; 3-ventilation pipes; 4-a relief valve to be tested; 5-pressure detection point.
Detailed Description
Further advantages and effects of the present invention will become readily apparent to those skilled in the art from the disclosure herein, by referring to the accompanying drawings and the preferred embodiments. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention. It should be understood that the preferred embodiments are presented by way of illustration only and not by way of limitation.
It should be noted that the illustrations provided in the following embodiments merely illustrate the basic concept of the present invention by way of illustration, and only the components related to the present invention are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complicated.
Example 1
As shown in fig. 1, a testing device for the outlet area of a pressure relief valve comprises an air supply device 1 and a static pressure cavity 2;
the static pressure cavity 2 is a cuboid with a hollow inside, an air inlet 21 is arranged on the left side surface 23 near the top surface, an air outlet 22 is arranged on the front surface 24 near the bottom surface, the air supply equipment 1 is communicated with the air inlet 21 through a ventilation pipe 3, a pressure relief valve 4 to be tested is inlaid at the air outlet 22, and the contact surface between the pressure relief valve 4 to be tested and the static pressure cavity 2 is sealed by an adhesive tape;
in order to ensure that the pressure measurement result of the pressure detection point is static pressure, the position of the pressure detection point needs to completely avoid the air inlet flow, and the wind speed of the pressure detection point is zero, so that the pressure detection point 5 is arranged at the inner wall surface of the static pressure cavity 2, which is close to the front surface 24, of the lower side of the air outlet 22;
wherein, in order to ensure the stability of the air supply device and the fitting property of the measurement data, the air supply amount of the air supply device needs to be controlled at 20m 3 /h -400m 3 The ventilation pipe 3 is a circular air pipe; the purpose of locating the inlet 21 and outlet 22 of the hydrostatic chamber 2 on adjacent sides is, on the one hand, to simulate the flow path of the air flow close to the real vehicle and, on the other hand, to ensure adequate mixing of the air flow inside the hydrostatic chamber.
The testing device in the embodiment is suitable for testing the automobile exhaust pressure release valve.
Example 2
As shown in fig. 2, a method for testing the outlet area of an automobile exhaust valve by using the testing device in embodiment 1 includes the following steps:
s1, embedding a pressure relief valve to be tested at an air outlet of a static pressure cavity, enabling air to flow into the static pressure cavity through an air supply device, and discharging the air from the pressure relief valve to be tested after the air is stabilized in the static pressure cavityA pressure detection point is arranged in the static pressure cavity, and different air quantities Q are monitored and fed back through the pressure detection point 1 The corresponding pressure value P 1 Wherein the air quantity Q 1 An initial value of 25m 3 And/h, the increment of the air quantity is 20-30m 3 And/h, monitoring and feeding back the air supply quantity Q in real time through a pressure detection point 1 From 25 to 25m 3 The/h gradually increases to 325m 3 Different pressures P in the process of/h 1 The resulting pressure P 1 And the air quantity Q 1 Performing a second fit to the plurality of sets of data to obtain the equation:
P 1 = a×Q 1 2 + b×Q 1 （Ⅰ）
Q 1 represents the air quantity, and the unit is m 3 /h，P 1 Representing pressure, wherein the unit is Pa, and a and b are fitting coefficients;
s2, establishing a finite element model with the same size as a testing device in STARCCM+simulation software, setting an air outlet of air supply equipment as an inlet boundary of the whole finite element model, setting a boundary type as a mass flow inlet, simplifying a pressure release valve outlet as a rectangular outlet, setting a boundary type as a pressure outlet, and setting the boundary pressure of the pressure outlet as 1.01x10 5 Pa, the boundary types of the static pressure cavities are all set to be wall surfaces;
the mounting positions of the air supply equipment, the ventilation pipe and the pressure relief valve in the finite element model are consistent with the mounting positions of the test device; the ventilation pipe has the function of ensuring that the air inlet flow in the finite element model is developed fully, thereby truly simulating the uniform air supply characteristic of the air supply equipment, being beneficial to the convergence of the finite element model and leading the calculation result to be more similar to the real result; the Y-direction width of the pressure outlet is kept unchanged;
the simulation physical model used for calculating the related data is K-Epsilon turbulence model selected in STARCCM+simulation software, and a separation solver is adopted to solve a steady-state Reynolds average Navier-Stokes equation;
s3, giving the air quantity Q 2 After being converted into the mass flow, the mass flow is assigned to an inlet boundary, then the first initial calculation is carried out, the mass flow is stabilized after the step 499 is iterated, and the S is operated according to the position of a pressure detection point in the testing deviceTARCCM+simulation software to calculate the pressure P at the same position 2 ；
Wherein the mass flow rate m 2 And a given air quantity Q 2 The conversion formula of (2) is as follows: m is m 2 =Q 2 X ρ/3600, ρ is air density at 25℃and the value is 1.185kg/m 3 The method comprises the steps of carrying out a first treatment on the surface of the Given air quantity Q 2 Is close to the air quantity Q 1 Or given air quantity Q 2 The value of the air quantity Q is equal to that of the air quantity 1 ；
S4, giving the air quantity Q 2 And then is carried into an equation (I), and a theoretical pressure value P is calculated 2,c =f 1 (Q 2 ) Judgment of P 2 And P 2,c Is a difference deltaP of (1) 2 When |ΔP 2 When the I is less than or equal to 0.5Pa, outputting the outlet area S of the pressure relief valve and the test pressure P of the detection point 2 ；
Wherein DeltaP 2 =P 2 -P 2,c When |ΔP 2 When the I is more than 0.5Pa, the Z-direction height of a pressure outlet in the finite element model is directly adjusted in the next iterative calculation according to the difference value by utilizing the functions of shaping and Field function custom functions in STARCCM+simulation software, namely the outlet area of a pressure release valve outlet is adjusted, and iterating is carried out for 499 steps until the I delta P is reached 2 The I is less than or equal to 0.5Pa, and then the outlet area S and the pressure P of the pressure relief valve at the moment are output 2 ；
Wherein the initial value H of the Z-direction height of the pressure outlet is 55mm, and the initial value of the outlet area of the corresponding pressure relief valve outlet is 4950mm 2 ；
The method for adjusting the Z-direction height of the pressure outlet comprises the following steps:
newly building a deformation motion node in the motion node, and applying the deformation in the physical value node in the Region node;
based on Morhper, after setting each 499 iteration steps in a steady state calculation process, the next step is to adjust the physical position of the upper outline of the pressure outlet boundary according to an error range control logic, the upper outline of the pressure outlet boundary can move up and down along with control parameters in the steady state calculation process, the positions of grid nodes of the left boundary, the right boundary and the lower boundary are kept unchanged, and the Z-direction height of the pressure outlet boundary is stretched to be larger (delta H > 0) or compressed to be smaller (delta H < 0) according to the up-down movement quantity delta H;
as shown in fig. 3, when the outlet area of the pressure release valve is adjusted, i.e. the Z-directional height of the pressure outlet boundary is adjusted, the adjustment manner of the variable Δh of the Z-directional height is as follows:
(1) when the iteration step number is not an integer multiple of 500, Δh=0;
(2) when the iteration step number is an integer multiple of 500, ΔP 2 Δh=0.011 m at > 10 Pa;
(3) when the iteration step number is an integer multiple of 500, ΔP 2 Δh=0.0011 m at 0.5 Pa;
(4) when the iteration step number is an integer multiple of 500, ΔP 2 When the pressure is less than or equal to-10 Pa, delta H= -0.011m;
(5) when the iteration step number is an integer multiple of 500, ΔP 2 When the pressure is less than or equal to-0.5 Pa, delta H= -0.0011m.
Based on Field function, when ΔP 2 When the absolute value of (a) is larger than the set error value, steady-state calculation is continuously performed, and logic judgment is performed every 499 iteration steps until |delta P 2 |≤0.5Pa；
S5, changing the air quantity Q 2 Repeating the steps S3-S4 to obtain different pressures P 2 The outlet area S of the corresponding relief valve is repeated to obtain at least five groups (P 2 After S) data, the pressure P is applied 2 Fitting to the exit area S yields the equation:
S =c × arctan(P 2 ) -d, wherein P 2 Expressed in Pa, S expressed in outlet area, and m 2 And c and d are fitting coefficients.
In summary, in the method for testing the outlet area of the pressure release valve in the embodiment, by constructing a simple test device for simulating the air quantity and pressure of the pressure release valve, the air supply equipment in the test device controls the air quantity entering the static pressure cavity, so that the pressure in the static pressure cavity is changed, and then the outlet area of the automobile exhaust pressure release valve under different static pressure conditions can be accurately calculated by combining with STARCCM+simulation software, so that the exhaust performance of the pressure release valve can be truly and effectively evaluated, and the method has popularization and application values in the technical field of automobile air conditioner ventilation systems.
The above embodiments are merely preferred embodiments for fully explaining the present invention, and the scope of the present invention is not limited thereto. Equivalent substitutions and modifications will occur to those skilled in the art based on the present invention, and are intended to be within the scope of the present invention.
Claims (11)
1. The method for testing the outlet area of the pressure release valve is characterized by comprising the following steps of:
s1, building a testing device, wherein the testing device comprises an air supply device and a static pressure cavity which are connected, and a relief valve to be tested is embedded at an air outlet of the static pressure cavity to obtain different air volumes Q 1 The corresponding pressure value P 1 Pressure P 1 And the air quantity Q 1 Fitting to obtain an equation:
P 1 =f 1 (Q 1 ) （Ⅰ）
Q 1 represents the air quantity, and the unit is m 3 /h，P 1 Pressure is expressed in Pa;
s2, establishing a corresponding finite element model in simulation software according to a testing device, setting an air outlet of air supply equipment as an inlet boundary of the whole finite element model, setting a boundary type as a mass flow inlet, simplifying an outlet of a pressure release valve as a rectangular outlet, setting a boundary type as a pressure outlet, and setting boundary types of static pressure cavities as wall surfaces;
s3, giving the air quantity Q 2 After the conversion into mass flow, assigning the mass flow to an inlet boundary, performing initial calculation for the first time, iterating until the residual value is smaller than a set value, and calculating the pressure P at the same position in simulation software according to the position of a pressure detection point in the testing device 2 ；
S4, giving the air quantity Q 2 And then is carried into an equation (I), and a theoretical pressure value P is calculated 2,c =f 1 (Q 2 ) Judgment of P 2 And P 2,c Is a difference deltaP of (1) 2 If the absolute value of (2) is less than or equal to the set error value, if so, outputting the outlet area S and the pressure of the relief valveForce P 2 ；
S5, changing the given air quantity Q 2 Repeating the steps S3-S4 to obtain different pressures P 2 The pressure P is set by the outlet area S of the corresponding relief valve 2 Fitting to the exit area S yields the equation:
S=f 2 (P 2 ) （Ⅱ）
P 2 expressed in Pa, S expressed in m, and the outlet area of the relief valve 2 。
2. The test method according to claim 1, wherein in S4, if P 2 And P 2,c Is a difference deltaP of (1) 2 When the absolute value of (a) is larger than the set error value, the Z-direction height of the pressure outlet in the finite element model is directly adjusted in the next iterative calculation according to the difference value by utilizing the function of forming and Field function custom function in simulation software, and iterating to the set step number until P is reached 2 And P 2,c Is a difference deltaP of (1) 2 The absolute value of (2) is smaller than or equal to the set error value, and then the outlet area S and the pressure P of the pressure relief valve at the moment are output 2 。
3. The method according to claim 2, wherein the Z-direction height of the pressure outlet is adjusted by an amount corresponding to ΔP 2 Proportional to the ratio.
4. A test method according to claim 3, wherein the simulation software is starccm+ simulation software.
5. The method according to claim 4, wherein the method for adjusting the Z-direction height of the pressure outlet is:
newly building a shaping motion node in the motion node;
based on Morhper, setting the iteration step number of each 499 in the steady state calculation process, and then adjusting the physical position of the upper outline of the boundary of the pressure outlet according to the error range control logic to realize the stretching and compression of the pressure outlet in the Z direction;
based on Field function, when ΔP 2 When the absolute value of (a) is larger than the set error value, steady-state calculation is continuously performed, and logic judgment is performed every 499 iteration steps until deltaP is reached 2 The absolute value of (a) is smaller than the set error value.
6. The test method according to claim 1, wherein in S1, wind is flowed into the static pressure cavity by the air supply device, the wind is discharged from the relief valve to be tested after being stabilized in the static pressure cavity, a pressure detection point is arranged in the static pressure cavity, and different wind volumes Q are fed back through the pressure detection point monitoring 1 The corresponding pressure value P 1 Pressure P 1 And the air quantity Q 1 Fitting to obtain an equation:
P 1 =f 1 (Q 1 ) （Ⅰ）
Q 1 represents the air quantity, and the unit is m 3 /h，P 1 Pressure is expressed in Pa.
7. The test method of claim 1, wherein in S1, equation (I) is P 1 = a×Q 1 2 + b×Q 1 Wherein Q is 1 Represents the air quantity, and the unit is m 3 /h，P 1 Representing pressure, wherein the unit is Pa, and a and b are fitting coefficients;
in S5, equation (ii) is s=c×arctan (P 2 ) -d, wherein P 2 Expressed in Pa, S expressed in m, and the outlet area of the relief valve 2 And c and d are fitting coefficients.
8. The test method according to claim 1, wherein the air supply amount of the inlet boundary is 25m 3 /h~325m 3 Between/h, the difference between the adjacent two air supply amounts is not more than 50m 3 /h；
The boundary pressure of the pressure outlet is 1.01X10 5 Pa；
The error value was set to 0.5Pa.
9. A device for testing the outlet area of a pressure relief valve based on the testing method according to any one of claims 1 to 8, characterized by comprising an air supply device (1) and a static pressure chamber (2);
the static pressure cavity (2) is a cuboid with a hollow inside, an air inlet (21) is formed in one side, an air outlet (22) is formed in the side adjacent to the side with the air inlet (21), the air supply equipment (1) is communicated with the air inlet (21) through a ventilation pipe (3), the air outlet (22) is used for placing a pressure relief valve (4) to be tested, so that air entering the static pressure cavity (2) is discharged from the pressure relief valve (4) to be tested, and a pressure detection point (5) is formed in the static pressure cavity (2) at the lower side of the air outlet (22).
10. The test device according to claim 9, wherein the air inlet (21) is located on the left side (23) or the right side near the top surface and the air outlet (22) is located on the front side (24) or the back side near the bottom surface.
11. Test device according to claim 10, characterized in that the pressure detection point (5) is located near the inner wall surface of the front face (24), and the ventilation tube (3) is a circular tube.
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