Counter-pressure atomization device, system and method for measuring high counter-pressure PDPA atomized particle size

Abstract

The application provides a back pressure atomization device, a system and a method for measuring high back pressure PDPA atomization particle size, and can solve the problem that when the constant volume combustion bomb is used for atomization experiment, the injection of gas working medium will make the pressure in the constant volume combustion bomb unstable, and back mist will appear when the injection flow is large, and the system is not suitable for gas-liquid injector. In the device, the PDPA particle size measurement module comprises a shell, a mounting flange, a quartz glass window and a window blowing unit, the upper end of the back mist collecting bin is connected with the lower end of the shell, the first through hole is arranged on the lower end surface, the gas-liquid discharge bin comprises a bin seat provided with a second through hole at the bottom, a bin chamber arranged on the bin seat, a partition plate arranged in the bin chamber, a normally open throat exhaust pipe and a pneumatic valve exhaust pipe in communication with the first through hole, a liquid discharge pipe in communication with the second through hole and a baffle assembly, the partition plate divides the bin chamber into an upper bin chamber and a lower bin chamber, the mounting notch for mounting the baffle assembly is arranged on the side wall of the lower bin chamber, and the lower end of the back mist collecting bin is connected with the partition plate through the upper bin chamber.

Description

TECHNICAL FIELD

[0001] The present application relates to a system and method for measuring atomized particle size, in particular to a back pressure atomization device, a system and method for measuring high back pressure PDPA (phase Doppler particle analyzer) atomized particle size. BACKGROUND

[0002] The droplet evaporation quality has a great influence on the combustion process in the rocket engine combustion chamber, and the time required for droplet evaporation is proportional to the square of the droplet particle size. In order to accelerate the combustion process, the propellant components must be atomized into fine droplets, and the larger the average diameter of the droplet atomization, the longer the time required for combustion, which will directly affect the energy space distribution of the combustion heat release and the dynamic response characteristics of the injector. Therefore, accurate measurement of the atomized droplet particle size of the injector is very important for the study of the dynamic response characteristics of the injector and the influencing factors of oscillating combustion.

[0003] At present, the atomization experiment of the injector is usually carried out in the atmospheric environment, and since the atomized droplet particle size of the injector is closely related to the density of the surrounding gas, the gas density in the atmospheric environment is constant, and the gas density in the real engine cannot be simulated, so the measurement result of the atomized particle size in the atmospheric environment deviates from the atomized particle size in the real engine. In order to solve the above problem, a static constant volume bomb is usually used for atomization experiment at present, and the gas is filled into the constant volume bomb before the experiment, and then the high back pressure atomization experiment is carried out after the constant volume bomb is sealed. However, when the static constant volume bomb is used for atomization experiment, the injection of gas working medium will make the pressure in the constant volume bomb unstable, and the back mist problem will occur when the injection flow is large, which is not suitable for gas-liquid injectors. SUMMARY

[0004] The purpose of the present application is to solve the technical problem that when the static constant volume bomb is used for atomization experiment, the injection of gas working medium will make the pressure in the constant volume bomb unstable, and the back mist problem will occur when the injection flow is large, which is not suitable for gas-liquid injectors, and to provide a back pressure atomization device, a system and method for measuring high back pressure PDPA atomized particle size.

[0005] In order to achieve the above purpose, the present application adopts the following technical scheme:

[0006] A back pressure atomization device, characterized in that:

[0007] The back pressure atomization device comprises a PDPA particle size measurement module, a back mist collection bin and a gas-liquid discharge bin which are arranged in sequence from top to bottom.

[0008] The PDPA particle size measurement module includes a housing, a mounting flange provided at the upper end of the housing, three quartz glass windows provided on the side wall of the housing and distributed at 120 degrees, and three window blowing units provided at the upper end of the housing and corresponding to the three quartz glass windows respectively; the mounting flange is used to install an injector; quartz glass is installed in the quartz glass window; the blowing end of the window blowing unit is close to the inner wall surface of the corresponding quartz glass;

[0009] The upper end of the anti-mist collection chamber is connected to the lower end of the shell, a pressure measuring interface for connecting to a pressure sensor is provided on the side wall of the anti-mist collection chamber, and two first through holes are provided on the lower end surface of the anti-mist collection chamber;

[0010] The gas-liquid discharge bin includes a bin chamber, a bin seat, a partition, a normally open throat exhaust pipe, a pneumatic valve exhaust pipe, a liquid discharge pipe and two baffle assemblies; the bin chamber is arranged on the bin seat; the partition is arranged in the bin chamber to separate the bin into an upper bin and a lower bin, an exhaust port is arranged on the side wall of the upper bin, and mounting notches are opened on the two opposite side walls of the lower bin; the lower end of the anti-mist collection bin passes through the upper end face of the upper bin and is connected to the partition; a plurality of exhaust holes are arranged on the edge of the partition; the normally open throat exhaust pipe and the pneumatic valve The air inlet end of the door-type exhaust pipe is passed through the partition and is respectively connected to the two first through holes. The normally open throat exhaust pipe and the pneumatic valve-type exhaust pipe are both located in the lower chamber, and the air outlet end of the normally open throat exhaust pipe is provided with a replaceable throat; a second through hole is provided at the bottom of the chamber seat; the drain pipe is provided at the bottom of the chamber seat and is connected to the second through hole; the two baffle assemblies are respectively installed at the two mounting notches, for dissipating the momentum of the gas-liquid mixture ejected from the pneumatic valve-type exhaust pipe and the throat, thereby achieving gas-liquid separation.

[0011] Furthermore, the upper end of the anti-mist collection bin is flange-connected to the lower end of the shell;

[0012] The middle portion of the partition is provided with a central hole and an annular groove located at the outer edge of the central hole; the lower end of the anti-mist collection bin passes through the upper end surface of the upper chamber and is connected to the annular groove;

[0013] The gas-liquid discharge bin further includes two crossbeams arranged on the lower surface of the partition, the two crossbeams being located on both sides of the installation notch;

[0014] Each of the baffle components includes a baffle cover, a transverse baffle, and two vertical baffles. The baffle cover is installed at the installation notch. One end of the transverse baffle and the two vertical baffles are connected to the inner wall of the baffle cover. The other ends of the transverse baffle and the two vertical baffles extend into the lower chamber. The two vertical baffles are respectively connected to two opposite side walls of the transverse baffle. The other end of the transverse baffle is provided with two arc-shaped notches. The four arc-shaped notches of the two transverse baffles are assembled into two through holes.

[0015] The air inlet ends of the normally open throat exhaust pipe and the pneumatic valve type exhaust pipe respectively pass through two through holes and are arranged at the center hole, and are communicated with the two first through holes through flanges.

[0016] Further, the quartz glass has a size of 115mm*145mm*45mm, and an effective observation area of 85mm*100mm.

[0017] The inner diameter of the shell is 200mm-300mm.

[0018] The exhaust port is a rectangular exhaust port.

[0019] The baffle is uniformly provided with 12 exhaust holes with a diameter of 90mm along the edges.

[0020] Meanwhile, the application also provides a system for measuring high back pressure PDPA atomized particle size, which is characterized in that:

[0021] The system comprises the back pressure atomization device, a gas-liquid supply unit, a PDPA, an automatic timing controller, a delay pulse signal generator and a high-speed data acquisition instrument.

[0022] The gas-liquid supply unit is used for supplying gas to the three window blowing units, supplying gas and liquid to the injector on the mounting flange.

[0023] The PDPA comprises a laser emission probe, a receiving probe, a processor and software, the laser emission probe and the receiving probe correspond to the positions of two quartz glass windows respectively, and the laser emission probe and the receiving probe are arranged in a 120° refraction light path; the receiving probe is provided with three receivers for receiving scattered light signals; the processor is electrically connected with the laser emission probe, the receivers, the software and the delay pulse signal generator, and is used for controlling the laser emission probe to emit laser beams, collecting the scattered light signals received by the receivers, sending the scattered light signals to the software and receiving the TTL trigger signals sent by the delay pulse signal generator.

[0024] The automatic timing controller is electrically connected with the gas-liquid supply unit, the pneumatic valve on the pneumatic valve type exhaust pipe and the delay pulse signal generator, and is used for controlling the gas-liquid supply unit to supply or stop supplying gas to the three window blowing units, supplying or stopping supplying gas and liquid to the injector, opening or closing the pneumatic valve and controlling the delay pulse signal generator to send TTL trigger signals to the processor.

[0025] The high-speed data acquisition instrument is electrically connected with the gas-liquid supply unit, the pressure sensor on the pressure measuring interface, the pneumatic valve and the delay pulse signal generator, and is used for collecting the gas supply and liquid supply signals of the gas-liquid supply unit, the gas supply pressure and flow, the liquid supply pressure and flow, the pressure in the shell, the opening and closing signals of the pneumatic valve and the TTL trigger signal in real time.

[0026] Further, the gas-liquid supply unit comprises a gas supply branch and a liquid supply branch; the gas supply branch is communicated with the gas inlet ends of the three window blowing units respectively, and is used for being communicated with the sprayer on the mounting flange; the liquid supply branch is used for being communicated with the sprayer;

[0027] The automatic timing controller is electrically connected with the first valve and the second valve on the gas supply branch, the third valve on the liquid supply branch, the pneumatic valve on the pneumatic valve type exhaust pipe and the delay pulse signal generator respectively, and is used for opening and closing the first valve, the second valve, the third valve and the pneumatic valve, and controlling the delay pulse signal generator to send the TTL trigger signal to the processor;

[0028] The high-speed data acquisition instrument is electrically connected with the first valve, the second valve, the third valve, the pressure sensor and the flow meter on the gas supply branch, the pressure sensor and the flow meter on the liquid supply branch, the pressure sensor on the pressure measuring interface, the pneumatic valve and the delay pulse signal generator respectively, and is used for collecting the opening and closing signals of the first valve, the second valve and the third valve, the gas supply pressure and flow, the liquid supply pressure and flow, the pressure in the shell, the opening and closing signals of the pneumatic valve and the TTL trigger signal in real time.

[0029] Further, the monitoring device is used for monitoring the blowing effect of the quartz glass in the quartz glass window in real time.

[0030] The pressure range in the shell is 1000Pa-6MPa.

[0031] Meanwhile, the application also provides a method for measuring high back pressure PDPA atomized particle size, based on the above-mentioned system for measuring high back pressure PDPA atomized particle size, and the speciality thereof lies in comprising the following steps:

[0032] Step 1, parameter calibration of the back pressure atomization device and the PDPA;

[0033] Record the thickness x of the quartz glass corresponding to the receiving probe g The distance x between the intersection of the inner wall surface of the quartz glass and the laser beam emitted by the laser emitting probe before refraction a1 The distance x between the outer wall surface of the quartz glass and the receiving probe a2and the angle θ between the laser beam pair before refraction; setting the angle ψ between the propagation direction of the scattered light signal received by any two receivers in the receiving probe and the scattering plane before refraction i and ψ j ; The scattering plane is a plane formed by the optical axis of the laser emitting probe and the optical axis of the receiving probe;

[0034] Step 2: First, close the pneumatic valve through the automatic timing controller, and then control the gas-liquid supply unit to supply air to the window blowing unit. The air enters the housing and the anti-fog collection chamber through the window blowing unit, so that the pressure in the anti-fog collection chamber gradually increases. After reaching the target back pressure, the air intake rate and the exhaust rate of the normally open throat exhaust pipe are in dynamic balance. At the same time, start the high-speed data acquisition instrument to collect the pressure in the housing, the switch signal of the pneumatic valve, and the air supply signal of the gas-liquid supply unit in real time.

[0035] Step 3: The laser emitting probe emits a laser beam pair by controlling the processor, and the automatic timing controller is used to control the gas-liquid supply unit to supply gas and liquid to the injector. The gas-liquid mixture is atomized by the injector and then injected into the shell; the laser beam pair irradiates the atomized droplets and scatters them, and the two receivers respectively receive the scattered light signals, and the automatic timing controller is used to control the delayed pulse signal generator to send a TTL trigger signal to the processor. The processor collects the scattered light signal and sends it to the software to calculate the atomized particle size D of the gas-liquid mixture; at the same time, the high-speed data acquisition instrument collects the gas and liquid supply signals, gas supply pressure and flow, liquid supply pressure and flow, and TTL trigger signal of the gas-liquid supply unit in real time; finally, the pneumatic valve is opened by the automatic timing controller to control the gas-liquid supply unit to stop supplying gas to the window blowing unit and the injector, and supplying liquid to the injector;

[0036] Step 4: Calculate the real-time air refractive index n inside the shell using the pressure p inside the shell collected in real time in step 2;

[0037] Step 5: Based on the θ recorded in step 1 and the n calculated in step 4, calculate the angle θ' between the laser beams after refraction and the relative refractive index n' of the atomized droplet to air under the target back pressure. rel ; According to the x recorded in step 1 g 、x a1 、x a2 , ψ i , ψ j And n calculated in step 4, respectively calculate the angle ψ between the propagation direction of the scattered light signal received by the two receivers 321 after refraction and the scattering plane i 'He ψ' j ;

[0038] Step 6: Use the θ' and n' calculated in step 5rel , ψ i , ψ j The D calculated in step 3 is modified and updated to complete the measurement of the high back pressure PDPA atomization particle size.

[0039] Further, in step 3, the atomization particle size D of the gas-liquid mixture is calculated according to the following formula:

[0040]

[0041] Wherein, Φ ij is the phase difference of the scattered light signals received by the two receivers (321), λ is the laser wavelength, and the geometric parameters of one of the receivers Relative refractive index of atomized droplets-air under standard state n p is the refractive index of the atomized droplets, n0 is the refractive index of air under standard state, n0 = 1.000277957, is the included angle between the center line of the receiving probe and the center line of the laser emitting probe, and the geometric parameter β j of the other receiver is calculated in the same way as the calculation method of β i ;

[0042] In step 4, the real-time air refractive index n in the shell 111 is calculated according to the following formula:

[0043]

[0044] Wherein, T0 = 273.15 K, p0 = 0.1 MPa, and T is the real-time temperature in the shell.

[0045] Further, in step 5, the included angle θ' between the laser beams after refraction is calculated according to the following formula:

[0046]

[0047] Wherein, n a is the air refractive index outside the shell;

[0048] The relative refractive index n' of the atomized droplets-air under the target back pressure after refraction is calculated according to the following formula: rel

[0049]

[0050] The included angle ψ i ' between the propagation direction of the scattered light signal received by one of the receivers and the scattering plane after refraction is calculated according to the following formula:

[0051] ​

[0052] wherein n g is the refractive index of the quartz glass, x is the distance between the intersection of the laser beam pair and the receiving probe; the included angle ψ j between the propagation direction of the scattered light signal received by the other receiver after refraction and the scattering plane is calculated in the same way as ψ i .

[0053] Further, step 2 is specifically that the automatic timing controller is used to first close the pneumatic valve on the pneumatic valve exhaust pipe, then open the first valve on the air supply branch, air is filled into the shell and the anti-mist collection bin through the window blowing unit, the pressure in the anti-mist collection bin is gradually increased, and after the target back pressure is reached, the air inlet rate and the exhaust rate of the normally open throat exhaust pipe are in dynamic balance; at the same time, the high-speed data acquisition instrument is started to collect the pressure in the shell, the opening and closing signals of the pneumatic valve and the first valve in real time.

[0054] Step 3 is specifically that the laser emitting probe is used to emit a laser beam pair, the automatic timing controller is used to open the second valve on the air supply branch and the third valve on the liquid supply branch, the gas-liquid mixture is atomized through the injector and injected into the shell, the laser beam pair irradiates the atomized droplets and scatters, the two receivers receive the scattered light signals respectively, the automatic timing controller is used to control the delay pulse signal generator to send a TTL trigger signal to the processor, the processor collects the scattered light signals and sends them to the software, and the atomized particle size D of the gas-liquid mixture is calculated; at the same time, the high-speed data acquisition instrument is used to collect the opening and closing signals of the second valve on the air supply branch, the air supply pressure and flow, the opening and closing signals of the third valve on the liquid supply branch, the liquid supply pressure and flow, and the TTL trigger signal in real time; finally, the automatic timing controller is used to open the pneumatic valve and close the first valve, the second valve and the third valve to exhaust the gas.

[0055] The beneficial effects of the present application are as follows:

[0056] 1. The present application provides an anti-pressure atomization device and a system and method for measuring high anti-pressure PDPA atomized particle size, in the anti-pressure atomization device, because the normally open throat exhaust pipe, the pneumatic valve exhaust pipe and the anti-mist collection bin are arranged, a stable high-pressure environment can be provided, the anti-mist problem is effectively solved, and the method is suitable for PDPA particle size measurement. In addition, because the replaceable throat is arranged on the normally open throat exhaust pipe, the outlet area can be changed by replacing the throats with different hole diameters to establish the target back pressure required under different conditions. The anti-pressure atomization device can simulate the gas density in a real engine, thereby reducing the atomized particle size measurement deviation.

[0057] 2、The anti-mist collecting bin is provided with two first through holes in the application, which are communicated with the normally open throat exhaust pipe and the pneumatic valve type exhaust pipe respectively, so that the back pressure and the blowing airflow speed in the shell can be adjusted independently. The opening and closing of the pneumatic valve type exhaust pipe can adjust the blowing airflow speed of the window blowing unit. When the pneumatic valve type exhaust pipe is opened, the exhaust area of the anti-mist collecting bin is large, the blowing airflow speed is high, and the quartz glass can be blown. When the pneumatic valve type exhaust pipe is closed, the exhaust area of the anti-mist collecting bin is small, and the blowing gas functions as pressurization. After the back pressure increases to the target pressure, the blowing airflow speed is reduced, so that the continuity of blowing is ensured, and the atomization process of the injector is not affected. The window blowing unit, the normally open throat exhaust pipe and the pneumatic valve type exhaust pipe are used in the application, so that the liquid attached to the quartz glass can be blown, and an air film can be formed to keep the cleanliness of the quartz glass.

[0058] 3、The anti-mist atomization device is modularized in the application, the PDPA particle size measurement module is convenient to disassemble and replace, the annular groove is arranged to better position the anti-mist collecting bin, the cross beam is arranged to prevent the deformation of the partition plate, and the cross baffle and the vertical baffle are arranged to reduce the force of the high-speed gas-liquid mixture on the anti-mist atomization device. Under the joint action of the large-size quartz glass window, the shell with an inner diameter of 200mm to 300mm and the window blowing unit, the number and density of anti-mist liquid drops can be reduced, and the effective observation time can be prolonged.

[0059] 4、The three quartz glass windows in the system for measuring the high back pressure PDPA atomization particle size are strictly matched with the 120° primary refraction light path layout, so that the scattered light signal strength received by the receiving probe is the strongest, and the signal-to-noise ratio is the highest.

[0060] 5、In the method for measuring the high back pressure PDPA atomization particle size, the synchronous measurement accuracy of the pressure data in the shell and the PDPA atomization liquid drop particle size can reach 1ms, the measurement data of the high back pressure PDPA atomization particle size is corrected by using the method, and the measurement system error caused by the refraction of the quartz glass and the change of the air density can be reduced. BRIEF DESCRIPTION OF DRAWINGS

[0061] Figure 1 is a structural schematic diagram of the system for measuring the high back pressure PDPA atomization particle size of the application;

[0062] Figure 2 is a structural schematic diagram of the anti-mist atomization device embodiment of the application;

[0063] Figure 3 is a structural schematic diagram of the anti-mist atomization device embodiment of the application from another perspective;

[0064] Figure 4 is a top view of the anti-mist atomization device embodiment of the application;

[0065] Figure 5 is a cross-sectional view of the anti-mist collection bin and the gas-liquid discharge bin in the embodiment of the anti-pressure atomization device of the present application;

[0066] Figure 6 is a cross-sectional view of the anti-mist collection bin and the gas-liquid discharge bin in the embodiment of the anti-pressure atomization device of the present application;

[0067] Figure 7 is a structural schematic diagram of the baffle plate in the embodiment of the anti-pressure atomization device of the present application;

[0068] Figure 8 is a structural schematic diagram of the baffle assembly in the embodiment of the anti-pressure atomization device of the present application;

[0069] Figure 9 is a schematic diagram of the laser beam emission light path of the laser emission probe in the embodiment of the method for measuring the atomized particle size of the high anti-pressure PDPA of the present application (the dashed line in the figure is the emission light path of the laser beam before refraction, and the solid line is the emission light path of the laser beam after refraction);

[0070] Figure 10 is a schematic diagram of the receiving light path of the receiver in the receiving probe in the embodiment of the method for measuring the atomized particle size of the high anti-pressure PDPA of the present application (the dashed line in the figure is the receiving light path of the receiver before refraction, and the solid line is the receiving light path of the receiver after refraction).

[0071] Legend of reference signs:

[0072] 1-anti-pressure atomization device; 11-PDPA particle size measurement module; 111-housing; 112-mounting flange; 113-quartz glass window; 114-window blowing unit; 12-anti-mist collection bin; 121-pressure measurement interface; 13-gas-liquid discharge bin; 130-bin chamber; 131-baffle plate; 132-constant-opening throat exhaust pipe; 133-pneumatic valve type exhaust pipe; 134-liquid discharge pipe; 135-baffle assembly; 136-exhaust hole; 137-exhaust port; 138-throat; 139-bin seat; 2-gas-liquid supply unit; 21-gas supply branch; 22-liquid supply branch; 23-first valve; 24-second valve; 25-third valve; 3-PDPA; 31-laser emission probe; 32-receiving probe; 321-receiver; 33-processor; 34-software; 4-automatic time sequence controller; 5-delayed pulse signal generator; 6-high-speed data acquisition instrument; 7-monitoring device; 8-quartz glass; 9-first through hole; 10-second through hole; 14-center hole; 15-annular groove; 16-cross beam; 17-block cover; 18-cross baffle; 19-vertical baffle; 20-arc-shaped notch. DETAILED DESCRIPTION

[0073] AsFigures 2-8As shown, a back pressure atomization device includes a PDPA particle size measurement module 11, a back mist collection bin 12 and a gas-liquid discharge bin 13 arranged in sequence from top to bottom. Specifically, the PDPA particle size measurement module 11 includes a shell 111, a mounting flange 112 arranged at the upper end of the shell 111, three quartz glass windows 113 arranged on the side wall of the shell 111 and distributed at an angle of 120°, and three window blow-off units 114 arranged at the upper end of the shell 111 and corresponding to the three quartz glass windows 113 respectively, wherein the mounting flange 112 is used to mount an injector, a quartz glass 8 is mounted in each quartz glass window 113, and the blow-off end of each window blow-off unit 114 is close to the inner wall surface of the corresponding quartz glass 8. The upper end of the back mist collection bin 12 is flange-connected with the lower end of the shell 111, a pressure measuring interface 121 for connecting a pressure sensor is arranged on the side wall of the back mist collection bin 12, and two first through holes 9 are arranged on the lower end surface of the back mist collection bin 12. The gas-liquid discharge bin 13 includes a bin chamber 130, a bin seat 139, a partition plate 131, a normally open throat portion exhaust pipe 132, a pneumatic valve type exhaust pipe 133, a liquid discharge pipe 134, two cross beams 16 and two baffle assemblies 135, wherein the bin chamber 130 is arranged on the bin seat 139, the partition plate 131 is arranged in the bin chamber 130, the partition plate 131 divides the bin chamber 130 into an upper bin chamber and a lower bin chamber, an exhaust port 137 is arranged on the side wall of the upper bin chamber, and installation notches are formed on two opposite side walls of the lower bin chamber. The middle part of the partition plate 131 is provided with a central hole 14 and an annular groove 15 located at the outer edge of the central hole 14, and 12 exhaust holes 136 with a diameter of 90 mm are uniformly distributed along the edge of the partition plate 131, and the lower end of the back mist collection bin 12 is connected with the annular groove 15 after penetrating through the upper end surface of the upper bin chamber. Each baffle assembly 135 includes a cover 17, a horizontal baffle 18 and two vertical baffles 19, the cover 17 is mounted at the installation notch, one end of the horizontal baffle 18 and the two vertical baffles 19 is connected with the inner wall of the cover 17, the other end of the horizontal baffle 18 and the two vertical baffles 19 extends into the lower bin chamber, the two vertical baffles 19 are respectively connected with two opposite side walls of the horizontal baffle 18, and two arc-shaped notches 20 are formed at the other end of each horizontal baffle 18, and four arc-shaped notches 20 of the two horizontal baffles 18 are combined into two through holes. The horizontal baffle 18 and the two vertical baffles 19 of each baffle assembly 135 are used to dissipate the momentum of the gas-liquid mixture sprayed by the pneumatic valve type exhaust pipe 133 and the throat portion 138, so as to realize gas-liquid separation. The gas inlet ends of the normally open throat portion exhaust pipe 132 and the pneumatic valve type exhaust pipe 133 penetrate through the two through holes respectively and are arranged at the central hole 14, and are communicated with the two first through holes 9 through flanges respectively, the normally open throat portion exhaust pipe 132 and the pneumatic valve type exhaust pipe 133 are located in the lower bin chamber, and the gas outlet end of the normally open throat portion exhaust pipe 132 is provided with a replaceable throat portion 138. The bottom of the bin seat 139 is provided with a second through hole 10, and the liquid discharge pipe 134 is arranged at the bottom of the bin seat 139 and communicated with the second through hole 10.Two beams 16 are connected to the lower surface of the partition 131, and are located on both sides of the mounting gap. In this embodiment, the quartz glass 8 has a size of 115 mm (L) x 145 mm (W) x 45 mm (H), the effective observation area has a size of 85 mm (L) x 100 mm (W), the inner diameter of the housing 111 is 200 mm to 300 mm, and the exhaust port 137 is a rectangular exhaust port.

[0074] As shown in Figure 1 The embodiment also provides a system for measuring high back pressure PDPA atomized particle size, which comprises the back pressure atomization device 1, and a gas-liquid supply unit 2, a PDPA 3, an automatic timing controller 4, a delay pulse signal generator 5, a high-speed data acquisition instrument 6, and a monitoring device 7. Specifically, the gas-liquid supply unit 2 comprises a gas supply branch 21 and a liquid supply branch 22. The gas supply branch 21 is in communication with the gas inlet ends of the three window blow-off units 114 respectively, and is used for supplying gas to the three window blow-off units 114. The gas supply branch 21 is used for being in communication with the injectors on the mounting flanges 112, and supplying gas to the injectors on the mounting flanges 112. The liquid supply branch 22 is used for being in communication with the injectors, and supplying liquid to the injectors on the mounting flanges 112.

[0075] The PDPA 3 comprises a laser emission probe 31, a receiving probe 32, a processor 33, and software 34. The laser emission probe 31 and the receiving probe 32 correspond to the positions of two quartz glass windows 113 respectively. The laser emission probe 31 and the receiving probe 32 are arranged in a 120° primary refraction light path. Three receivers 321 are arranged on the receiving probe 32, and are used for receiving scattered light signals. The processor 33 is electrically connected with the laser emission probe 31, the receivers 321, the software 34, and the delay pulse signal generator 5, and is used for controlling the laser emission probe 31 to emit a laser beam pair, collecting the scattered light signals received by the receivers 321, sending the scattered light signals to the software 34, and receiving a TTL trigger signal sent by the delay pulse signal generator 5.

[0076] The automatic timing controller 4 is electrically connected with a first valve 23 and a second valve 24 on the gas supply branch 21, a third valve 25 on the liquid supply branch 22, a pneumatic valve on the pneumatic valve type exhaust pipe 133, and the delay pulse signal generator 5, and is used for opening and closing the first valve 23, the second valve 24, the third valve 25, and the pneumatic valve, and controlling the delay pulse signal generator 5 to send a TTL trigger signal to the processor 33.

[0077] The high-speed data acquisition instrument 6 is electrically connected with the first valve 23, the second valve 24, the third valve 25, the pressure sensor and the flow meter on the gas supply branch 21, the pressure sensor and the flow meter on the liquid supply branch 22, the pressure sensor on the pressure connection 121, the pneumatic valve and the delay pulse signal generator 5, and is used for collecting the opening and closing signals of the first valve 23, the second valve 24 and the third valve 25, the gas supply pressure and flow, the liquid supply pressure and flow, the pressure in the shell 111, the opening and closing signals of the pneumatic valve and the TTL trigger signal in real time.

[0078] The monitoring device 7 corresponds to the position of the remaining one quartz glass window 113, and is used for monitoring the blowing effect of the quartz glass 8 in the quartz glass window 113 in real time. The pressure range in the shell 111 is 1000 Pa to 6 MPa.

[0079] As shown in Figures 9-10 , the embodiment also provides a method for measuring high back pressure PDPA atomized particle size, based on the above-mentioned system for measuring high back pressure PDPA atomized particle size, and specifically includes the following steps:

[0080] Step 1, parameter calibration of the back pressure atomization device 1 and the PDPA 3;

[0081] Record the thickness x of the quartz glass 8 corresponding to the receiving probe 32 g , the distance x between the inner wall surface of the quartz glass 8 and the intersection of the laser beam emitted by the laser emitting probe 31 before refraction a1 , the distance x between the outer wall surface of the quartz glass 8 and the receiving probe 32 a2 , and the included angle θ between the laser beam pairs before refraction; set the included angle ψ between the propagation direction of the scattered light signal received by any two receivers 321 in the receiving probe 32 and the scattering plane i and ψ j ; wherein the scattering plane is the plane formed by the optical axis of the laser emitting probe 31 and the optical axis of the receiving probe 32.

[0082] Step 2, the air supply branch 21 is opened by the automatic timing controller 4, and the first valve 23 is opened, and the air is filled into the shell 111 and the anti-fog collection bin 12 through the window blowing unit 114, so that the pressure in the anti-fog collection bin 12 gradually rises, and when the target back pressure is reached, the air inlet rate and the exhaust rate of the normally open throat exhaust pipe 132 are in dynamic balance, at this time the blowing air speed is reduced, but not 0, and the blowing air forms an air film on the inner wall of the quartz glass 8 to maintain the cleanliness of the quartz glass 8; at the same time, the high-speed data acquisition instrument 6 is started to collect the pressure in the shell 111, the opening and closing signals of the air valve and the first valve 23 in real time, which is used to check whether the pressure in the shell 111 is stable and whether the air valve and the first valve 23 are normally opened and closed.

[0083] Step 3, the laser emission probe 31 emits a laser beam pair, the second valve 24 on the air supply branch 21 and the third valve 25 on the liquid supply branch 22 are opened by the automatic timing controller 4, and the gas-liquid mixture is injected into the shell 111 after being atomized by the injector; the laser beam pair irradiates the atomized droplets and scatters, and the two receivers 321 in the receiving probe 32 receive the scattered light signals respectively, and the automatic timing controller 4 controls the delay pulse signal generator 5 to send a TTL trigger signal to the processor 33, and the processor 33 collects the scattered light signals and sends them to the software 34 to calculate the atomized particle size D of the gas-liquid mixture; at the same time, the high-speed data acquisition instrument 6 collects the opening and closing signals of the second valve 24 on the air supply branch 21, the air supply pressure and flow, the opening and closing signals of the third valve 25 on the liquid supply branch 22, the liquid supply pressure and flow, and the TTL trigger signal in real time, which is used to check whether the second valve 24 and the third valve 25 are normally opened and closed, whether the gas-liquid supply pressure and flow are consistent, and whether the TTL trigger signal is effectively recorded; finally, the air valve on the air valve type exhaust pipe 133 is opened by the automatic timing controller 4, and the first valve 23, the second valve 24 and the third valve 25 are closed, and the gas in the anti-fog collection bin 12 is exhausted, at this time the blowing air speed is increased, and the window blowing unit 114 strongly blows the quartz glass 8 to blow off the droplets attached to the quartz glass 8. The TTL trigger signal is the synchronization signal of the pressure data in the shell 111 and the PDPA3 measurement data; the atomized particle size D of the gas-liquid mixture is calculated according to the following formula:

[0084]

[0085] Wherein, Φ ij is the phase difference of the scattered light signals received by the two receivers 321, λ is the wavelength of the laser, and the geometric parameters of one of the receivers 321 Relative refractive index of atomized droplets-air under standard conditions np n0 is the refractive index of the atomized droplet, n0 is the refractive index of air under standard state, n0 = 1.000277957, is the included angle between the center line of the receiving probe 32 and the center line of the laser emitting probe 31, and the geometric parameter β of the other receiver 321 j The calculation method of β is the same as that of β i .

[0086] Step 4, according to the real-time pressure p in the shell 111 collected in step 2, the real-time air refractive index n in the shell 111 is calculated according to the following formula:

[0087]

[0088] Wherein, T0 = 273.15K, p0 = 0.1MPa, T is the real-time temperature in the shell 111.

[0089] Step 5, according to θ recorded in step 1 and n calculated in step 4, the included angle θ' between the laser beams emitted by the laser emitting probe 31 after refraction and the relative refractive index n' of the atomized droplet-air under the target counter pressure are calculated respectively rel ; According to x g , x a1 , x a2 , ψ i , ψ j in step 1 and n calculated in step 4, the included angles ψ i ' and ψ' j between the propagation direction of the scattered light signal received by the two receivers 321 and the scattering plane after refraction are calculated respectively; Specifically, θ' is calculated according to the following formula:

[0090]

[0091] Wherein, n a is the refractive index of air outside the shell 111;

[0092] n' rel is calculated according to the following formula:

[0093]

[0094] ψ i ' is calculated according to the following formula:

[0095]

[0096] Wherein, n g is the refractive index of quartz glass 8, and x is the distance between the intersection of the laser beam pair and the receiving probe 32; The calculation method of ψ' j is the same as that of ψi The calculation method is the same as that of θ'.

[0097] Step 6, using the calculated θ' and n' in step 5, rel , ψ i ', ψ' j , the D calculated in step 3 is updated and corrected, and the high back pressure PDPA atomization particle size measurement is completed.

[0098] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any change or replacement within the technical scope disclosed by the present application should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A back-pressure atomization device, characterized in that: It comprises a PDPA particle size measurement module (11), an anti-fog collection chamber (12) and a gas-liquid discharge chamber (13) which are arranged in sequence from top to bottom; The PDPA particle size measurement module (11) comprises a housing (111), a mounting flange (112) arranged at the upper end of the housing (111), three quartz glass windows (113) arranged on the side wall of the housing (111) and distributed at 120 degrees, and three window blowing units (114) arranged at the upper end of the housing (111) and corresponding to the three quartz glass windows (113) respectively; the mounting flange (112) is used to install an injector; quartz glass (8) is installed in the quartz glass window (113); the blowing end of the window blowing unit (114) is close to the inner wall surface of the corresponding quartz glass (8); The upper end of the anti-mist collection chamber (12) is connected to the lower end of the housing (111); a pressure measuring interface (121) for connecting to a pressure sensor is provided on the side wall of the anti-mist collection chamber (12); and two first through holes (9) are provided on the lower end surface of the anti-mist collection chamber (12); The gas-liquid discharge bin (13) comprises a bin chamber (130), a bin seat (139), a partition (131), a normally open throat exhaust pipe (132), a pneumatic valve type exhaust pipe (133), a liquid discharge pipe (134) and two baffle assemblies (135); the bin chamber (130) is arranged on the bin seat (139); the partition (131) is arranged in the bin chamber (130) to separate the bin chamber (130) into an upper bin and a lower bin, an exhaust port (137) is arranged on the side wall of the upper bin, and mounting notches are opened on two opposite side walls of the lower bin; the lower end of the anti-mist collection bin (12) passes through the upper end surface of the upper bin and is connected to the partition (131); a plurality of exhaust holes (136) are arranged along the edge of the partition (131); the normally open throat exhaust pipe (132) is provided with a plurality of exhaust holes (136) along the edge of the partition (131); the normally open throat exhaust pipe (132) is provided with a plurality of exhaust holes (136) along the edge of the partition (131); the normally open throat exhaust pipe (132) is provided with a plurality of exhaust holes (136) along the edge of the partition (131); the normally open throat exhaust pipe (132) is provided with a plurality of exhaust holes (136) The air inlet ends of the air pipe (132) and the pneumatic valve exhaust pipe (133) are passed through the partition (131) and are respectively communicated with the two first through holes (9); the normally open throat exhaust pipe (132) and the pneumatic valve exhaust pipe (133) are both located in the lower chamber, and the air outlet end of the normally open throat exhaust pipe (132) is provided with a replaceable throat (138); the bottom of the chamber seat (139) is provided with a second through hole (10); the liquid discharge pipe (134) is provided at the bottom of the chamber seat (139) and is communicated with the second through hole (10); the two baffle assemblies (135) are respectively installed at the two installation notches, and are used to dissipate the momentum of the gas-liquid mixture ejected from the pneumatic valve exhaust pipe (133) and the throat (138), thereby achieving gas-liquid separation.

2. The back-pressure atomization device according to claim 1, characterized in that: The upper end of the anti-mist collection bin (12) is flange-connected to the lower end of the housing (111); The middle portion of the partition (131) is provided with a central hole (14) and an annular groove (15) located at the outer edge of the central hole (14); the lower end of the anti-mist collection chamber (12) passes through the upper end surface of the upper chamber and is connected to the annular groove (15); The gas-liquid discharge bin (13) further includes two crossbeams (16) arranged on the lower surface of the partition (131), and the two crossbeams (16) are located on both sides of the installation gap; Each of the baffle components (135) includes a baffle cover (17), a transverse baffle (18) and two vertical baffles (19), wherein the baffle cover (17) is installed at the installation notch, one end of the transverse baffle (18) and the two vertical baffles (19) are connected to the inner wall of the baffle cover (17), the other ends of the transverse baffle (18) and the two vertical baffles (19) are extended into the lower chamber, the two vertical baffles (19) are respectively connected to two opposite side walls of the transverse baffle (18), the other end of the transverse baffle (18) is provided with two arc-shaped notches (20), and the four arc-shaped notches (20) of the two transverse baffles (18) are assembled into two through holes; The air inlet ends of the normally open throat exhaust pipe (132) and the pneumatic valve type exhaust pipe (133) respectively pass through the two through holes and are then arranged at the center hole (14), and are communicated with the two first through holes (9) through flanges.

3. The back-pressure atomization device according to claim 2, characterized in that: The size of the quartz glass (8) is 115mm×145mm×45mm, and the effective observation area is 85mm×100mm; The inner diameter of the housing (111) is 200 mm to 300 mm; The exhaust port (137) is a rectangular exhaust port; The partition (131) is evenly distributed along its edge with 12 exhaust holes (136) each having a diameter of 90 mm.

4. A system for measuring the particle size of high back-pressure PDPA atomization, characterized by: It comprises the back-pressure atomization device (1) according to any one of claims 1 to 3, as well as a gas-liquid supply unit (2), a PDPA (3), an automatic timing controller (4), a delayed pulse signal generator (5), and a high-speed data acquisition device (6); The gas-liquid supply unit (2) is used to supply gas to the three window blowing units (114) and to supply gas and liquid to the injectors on the mounting flange (112); The PDPA (3) comprises a laser emitting probe (31), a receiving probe (32), a processor (33) and software (34), wherein the laser emitting probe (31) and the receiving probe (32) respectively correspond to the positions of two quartz glass windows (113), and a 120° primary refraction optical path layout is provided between the laser emitting probe (31) and the receiving probe (32); three receivers (321) are provided on the receiving probe (32) for receiving scattered light signals; the processor (33) is electrically connected to the laser emitting probe (31), the receiver (321), the software (34) and the delayed pulse signal generator (5), and is used to control the laser emitting probe (31) to emit a laser beam pair, collect scattered light signals received by the receiver (321), send scattered light signals to the software (34), and receive a TTL trigger signal sent by the delayed pulse signal generator (5); The automatic timing controller (4) is electrically connected to the gas-liquid supply unit (2), the pneumatic valve on the pneumatic valve type exhaust pipe (133), and the time-delay pulse signal generator (5), respectively, and is used to control the gas-liquid supply unit (2) to supply or stop supplying gas to the three window blowing units (114), to supply or stop supplying gas and liquid to the injector, to switch the pneumatic valve, and to control the time-delay pulse signal generator (5) to send a TTL trigger signal to the processor (33); The high-speed data acquisition instrument (6) is electrically connected to the gas-liquid supply unit (2), the pressure sensor on the pressure measuring interface (121), the pneumatic valve and the delayed pulse signal generator (5) respectively, and is used to collect in real time the gas supply and liquid supply signals of the gas-liquid supply unit (2), the gas supply pressure and flow, the liquid supply pressure and flow, the pressure in the housing (111), the switch signal of the pneumatic valve, and the TTL trigger signal.

5. The system for measuring high back pressure PDPA atomized particle size according to claim 4, characterized in that: The gas-liquid supply unit (2) comprises a gas supply branch (21) and a liquid supply branch (22); the gas supply branch (21) is respectively connected to the gas inlet ends of the three window blowing units (114) and is used to communicate with the injector on the mounting flange (112); the liquid supply branch (22) is used to communicate with the injector; The automatic timing controller (4) is electrically connected to the first valve (23) and the second valve (24) on the gas supply branch (21), the third valve (25) on the liquid supply branch (22), the pneumatic valve on the pneumatic valve type exhaust pipe (133), and the delayed pulse signal generator (5), respectively, and is used to open and close the first valve (23), the second valve (24), the third valve (25), and the pneumatic valve, and control the delayed pulse signal generator (5) to send a TTL trigger signal to the processor (33); The high-speed data acquisition instrument (6) is electrically connected to the first valve (23), the second valve (24), the third valve (25), the pressure sensor and flowmeter on the gas supply branch (21), the pressure sensor and flowmeter on the liquid supply branch (22), the pressure sensor on the pressure measuring interface (121), the pneumatic valve and the delayed pulse signal generator (5), respectively, and is used for real-time acquisition of the switching signals of the first valve (23), the second valve (24) and the third valve (25), the gas supply pressure and flow, the liquid supply pressure and flow, the pressure in the housing (111), the switching signals of the pneumatic valve and the TTL trigger signal.

6. The system for measuring the atomized particle size of high back pressure PDPA according to claim 4 or 5, characterized in that: It also includes a monitoring device (7); the monitoring device (7) corresponds to the position of the remaining quartz glass window (113) and is used to monitor the blowing effect of the quartz glass (8) in the quartz glass window (113) in real time; The pressure range in the housing (111) is 1000 Pa to 6 MPa.

7. A method for measuring the particle size of atomized PDPA at high back pressure, based on the system for measuring the particle size of atomized PDPA at high back pressure according to any one of claims 4 to 6, characterized in that: The following steps are involved: Step 1, calibrating parameters of the back pressure atomization device (1) and the PDPA (3); Record the thickness x of the quartz glass (8) corresponding to the receiving probe (32) g , the distance x between the inner wall of the quartz glass (8) and the intersection point of the laser beam emitted by the laser emitting probe (31) before refraction occurs a1 , the distance x between the outer wall of the quartz glass (8) and the receiving probe (32) a2 and the angle θ between the laser beam pair before refraction occurs; setting the angle ψ between the propagation direction of the scattered light signal received by any two receivers (321) in the receiving probe (32) and the scattering plane before refraction occurs i and ψ j The scattering plane is a plane formed by the optical axis of the laser emitting probe (31) and the optical axis of the receiving probe (32); Step 2: First, the pneumatic valve is closed by the automatic timing controller (4), and then the gas-liquid supply unit (2) is controlled to supply air to the window blowing unit (114), and the air enters the housing (111) and the anti-fog collection chamber (12) through the window blowing unit (114), so that the pressure in the anti-fog collection chamber (12) gradually increases. After reaching the target back pressure, the air intake rate and the exhaust rate of the normally open throat exhaust pipe (132) are in dynamic balance; at the same time, the high-speed data acquisition instrument (6) is started to collect the pressure in the housing (111), the switch signal of the pneumatic valve and the air supply signal of the gas-liquid supply unit (2) in real time; Step 3: The laser emitting probe (31) emits a laser beam pair by controlling the processor (33), and the automatic timing controller (4) is used to control the gas-liquid supply unit (2) to supply gas and liquid to the injector. The gas-liquid mixture is atomized by the injector and injected into the housing (111); the laser beam pair irradiates the atomized droplets and scatters them, and the two receivers (321) respectively receive the scattered light signals, and the automatic timing controller (4) is used to control the delayed pulse signal generator (5) to send TTL signals to the processor (33). The trigger signal is received, and the processor (33) collects the scattered light signal and sends it to the software (34) to calculate the atomized particle size D of the gas-liquid mixture; at the same time, the high-speed data acquisition instrument (6) collects the gas supply and liquid supply signals, gas supply pressure and flow, liquid supply pressure and flow, and TTL trigger signal of the gas-liquid supply unit (2) in real time; finally, the pneumatic valve is opened through the automatic timing controller (4), and the gas-liquid supply unit (2) is controlled to stop supplying gas to the window blowing unit (114) and the injector, and supplying liquid to the injector; Step 4: Calculate the real-time air refractive index n in the housing (111) using the pressure p in the housing (111) collected in real time in step 2; Step 5: Based on the θ recorded in step 1 and the n calculated in step 4, calculate the angle θ' between the laser beams after refraction and the relative refractive index n' of the atomized droplet to air under the target back pressure. rel ; According to the x recorded in step 1 g 、x a1 、x a2 , ψ i , ψ j And n calculated in step 4, respectively calculate the angle ψ between the propagation direction of the scattered light signal received by the two receivers 321 after refraction and the scattering plane i 'He ψ' j ; Step 6: Use the θ' and n' calculated in step 5 rel , ψ i '、ψ' j The D calculated in step 3 is corrected and updated to complete the measurement of the high back pressure PDPA atomized particle size.

8. The method for measuring the atomized particle size of high back pressure PDPA according to claim 7, characterized in that: In step 3, the atomized particle size D of the gas-liquid mixture is calculated according to the following formula: Among them, Φ ij is the phase difference of the scattered light signals received by the two receivers (321), λ is the laser wavelength, and the geometric parameters of one of the receivers (321) are Relative refractive index of atomized liquid droplets and air under standard conditions n p is the refractive index of the atomized droplets, n0 is the refractive index of air under standard conditions, n0 = 1.000277957, is the angle between the center line of the receiving probe (32) and the center line of the laser emitting probe (31), and the geometric parameter β of the other receiver (321) is j The calculation method of β i The calculation method is the same; In step 4, the real-time air refractive index n in the housing 111 is calculated according to the following formula: Wherein, T0=273.15K, p0=0.1MPa, and T is the real-time temperature inside the shell (111).

9. The method for measuring the atomized particle size of high back pressure PDPA according to claim 8, characterized in that: In step 5, the angle θ' between the laser beams after refraction is calculated according to the following formula: Among them, n a is the refractive index of air outside the housing (111); The relative refractive index n' of the atomized droplet to air under the target back pressure after refraction is calculated according to the following formula rel : The angle ψ between the propagation direction of the scattered light signal received by one of the receivers (321) after refraction and the scattering plane is calculated according to the following formula: i ': Among them, n g is the refractive index of the quartz glass (8), x is the distance between the intersection point of the laser beam and the receiving probe (32); the angle ψ' between the propagation direction of the scattered light signal received by another receiver (321) after refraction and the scattering plane j The calculation method of ψ i ' is calculated in the same way.

10. The method for measuring the atomized particle size of high back pressure PDPA according to claim 7, characterized in that: Step 2 specifically comprises the following steps: firstly closing the pneumatic valve on the pneumatic valve type exhaust pipe (133) through the automatic timing controller (4), then opening the first valve (23) on the air supply branch (21), and allowing air to be filled into the housing (111) and the anti-fog collection chamber (12) through the window blowing unit (114), so that the pressure in the anti-fog collection chamber (12) gradually increases. After reaching the target back pressure, the air intake rate and the exhaust rate of the normally open throat exhaust pipe (132) are in dynamic balance; and simultaneously starting the high-speed data acquisition instrument (6) to collect the pressure in the housing (111), the switch signals of the pneumatic valve and the first valve (23) in real time; Step 3 specifically comprises: controlling the processor (33) to make the laser emitting probe (31) emit a laser beam pair; using the automatic timing controller (4) to open the second valve (24) on the gas supply branch (21) and the third valve (25) on the liquid supply branch (22); the gas-liquid mixture is atomized by the injector and then injected into the housing (111); the laser beam pair irradiates the atomized liquid droplets and scatters them; the two receivers (321) respectively receive the scattered light signals, and using the automatic timing controller (4) to control the delayed pulse signal generator (5) to send a TTL signal to the processor (33); The processor (33) collects the scattered light signal and sends it to the software (34) to calculate the atomized particle size D of the gas-liquid mixture; at the same time, the high-speed data acquisition instrument (6) collects the switch signal, gas supply pressure and flow of the second valve (24) on the gas supply branch (21), the switch signal, liquid supply pressure and flow of the third valve (25) on the liquid supply branch (22), and the TTL trigger signal in real time; finally, the pneumatic valve is opened through the automatic timing controller (4), and the first valve (23), the second valve (24) and the third valve (25) are closed to discharge the gas.

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