Back pressure atomization device and system and method for measuring high back pressure PDPA atomization particle size

Abstract

The invention provides a back pressure atomization device and a system and method for measuring high back pressure PDPA atomization particle size, and can solve the problems that when a constant volume combustion bomb is used for an atomization experiment, the injection of a gas working medium causes the pressure in the constant volume combustion bomb to be unstable, anti-fog occurs when the injection flow is relatively large, and the device is not suitable for a gas-liquid injector. According to the device, a PDPA particle size measurement module comprises a shell, a mounting flange, a quartz glass window and a window blowing unit, the upper end of an anti-fog collection bin is connected with the lower end of the shell, and a first through hole is formed in the lower end face of the anti-fog collection bin; a second through hole is formed in the bottom of the bin seat, the bin chamber is arranged on the bin seat, the partition plate is arranged in the bin chamber, the air inlet end of the normally-open throat exhaust pipe and the air inlet end of the pneumatic valve type exhaust pipe are communicated with the first through hole, the liquid drainage pipe is communicated with the second through hole, and the bin chamber is divided into an upper bin chamber and a lower bin chamber through the partition plate. The side wall of the lower chamber is provided with a mounting notch for mounting the baffle assembly, and the lower end of the anti-fog collecting chamber penetrates through the upper chamber to be connected with the partition plate.

Description

Technical Field

[0001] The present invention relates to a system and method for measuring atomized particle size, and in particular to a back-pressure atomization device, and a system and method for measuring atomized particle size of a high back-pressure PDPA (Phase Doppler Particle Analyzer). Background Art

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

[0003] At present, the atomization experiment of the injector is usually carried out under the atmospheric environment. Since the particle size of the atomized droplets of the injector is closely related to the density of the surrounding gas, and the gas density under the atmospheric environment is constant, it is impossible to simulate the gas density in the real engine. Therefore, the atomization particle size measurement result under the atmospheric environment deviates from the atomization particle size in the real engine. In order to solve the above problems, a static constant volume combustion bomb is usually used for atomization experiments. Before the experiment, the constant volume combustion bomb is first filled with gas, and then sealed to carry out a high back pressure atomization experiment. However, the problem when using the static constant volume combustion bomb for atomization experiments is that the injection of the gas working medium will make the pressure in the constant volume combustion bomb unstable, and the anti-fog problem will occur when the injection flow rate is large, which is not suitable for gas-liquid injectors. Summary of the invention

[0004] The purpose of the present invention is to solve the technical problem that when a static constant volume combustion bomb is used for atomization experiment, the injection of gas working fluid will make the pressure inside the constant volume combustion bomb unstable, and the back fog problem will occur when the injection flow rate is large, which is not suitable for a gas-liquid injector. Instead, a back pressure atomization device is provided, and a system and method for measuring the atomized particle size of high back pressure PDPA are provided.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A back pressure atomization device, which is special in that:

[0007] It includes a PDPA particle size measurement module, an anti-fog collection chamber and a gas-liquid discharge chamber which are arranged in sequence from top to bottom;

[0008] The PDPA particle size measurement module comprises a housing, a mounting flange arranged at the upper end of the housing, three quartz glass windows arranged on the side wall of the housing and distributed at 120°, and three window blowing units arranged 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-fog collection bin is connected to the lower end of the shell, a pressure measuring interface for connecting a pressure sensor is arranged on the side wall of the anti-fog collection bin, and two first through holes are arranged on the lower end surface of the anti-fog collection bin;

[0010] The gas-liquid discharge bin comprises 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, dividing the bin into an upper bin chamber and a lower bin chamber, an exhaust port is arranged on the side wall of the upper bin chamber, and installation notches are arranged on the two opposite side walls of the lower bin chamber; the lower end of the anti-fog collection bin passes through the upper end surface of the upper bin chamber 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 gate-type exhaust pipe is penetrated on the partition and is respectively connected with 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 with 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 sprayed out of the pneumatic valve-type exhaust pipe and the throat, thereby realizing 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 part 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-fog 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 comprises two cross beams arranged on the lower surface of the partition, and the two cross beams are located on both sides of the installation notch;

[0014] Each of the baffle components comprises 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, and 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 exhaust pipe are respectively passed through the two through holes and then arranged at the central hole, and are communicated with the two first through holes through flanges.

[0016] Furthermore, the size of the quartz glass is 115 mm × 145 mm × 45 mm, and the effective observation area is 85 mm × 100 mm;

[0017] The inner diameter of the shell is 200 mm to 300 mm;

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

[0019] The partition is evenly provided with 12 exhaust holes with a diameter of 90 mm along its edge.

[0020] At the same time, the present invention also provides a system for measuring the atomized particle size of high back pressure PDPA, which is special in that:

[0021] It includes the above-mentioned back pressure atomization device, as well as a gas-liquid supply unit, a PDPA, an automatic timing controller, a delayed pulse signal generator, and a high-speed data acquisition instrument;

[0022] The gas and liquid supply unit is used to supply gas to the three window blowing units and to supply gas and liquid to the injectors on the mounting flange respectively;

[0023] The PDPA includes a laser emitting probe, a receiving probe, a processor and software. The laser emitting probe and the receiving probe correspond to the positions of two quartz glass windows respectively, and a primary refraction optical path layout of 120° is provided between the laser emitting probe and the receiving probe; three receivers are arranged on the receiving probe for receiving scattered light signals; the processor is electrically connected to the laser emitting probe, the receiver, the software and the delayed pulse signal generator respectively, and is used to control the laser emitting probe to emit a laser beam pair, collect scattered light signals received by the receiver, send scattered light signals to the software, and receive TTL trigger signals sent by the delayed pulse signal generator;

[0024] The automatic timing controller is electrically connected to the gas-liquid supply unit, the pneumatic valve on the pneumatic valve exhaust pipe and the delayed pulse signal generator, respectively, and is used to control the gas-liquid supply unit to supply gas to the three window blow-off units or stop supplying gas, supply gas and liquid to the injector or stop supplying gas and liquid, switch the pneumatic valve, and control the delayed pulse signal generator to send a TTL trigger signal to the processor;

[0025] The high-speed data acquisition instrument is electrically connected to the gas-liquid supply unit, the pressure sensor on the pressure measuring interface, the pneumatic valve and the delayed pulse signal generator, and is used to collect the gas 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 switch signal 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 respectively connected to the gas inlet ends of the three window blowing units and is used to communicate with the injector on the mounting flange; the liquid supply branch is used to communicate with the injector;

[0027] The automatic timing controller is electrically connected to 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 exhaust pipe and the delayed pulse signal generator, respectively, and is used to switch the first valve, the second valve, the third valve and the pneumatic valve, and control the delayed pulse signal generator to send a TTL trigger signal to the processor;

[0028] The high-speed data acquisition instrument is electrically connected to the first valve, the second valve, the third valve, the pressure sensor and flowmeter on the gas supply branch, the pressure sensor and flowmeter on the liquid supply branch, the pressure sensor on the pressure measuring interface, the pneumatic valve and the delayed pulse signal generator, and is used for real-time acquisition of the switching 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 switching signals of the pneumatic valves and the TTL trigger signals.

[0029] Furthermore, it also includes a monitoring device; the monitoring device corresponds to the position of the remaining quartz glass window and is used to monitor the blowing effect of the quartz glass in the quartz glass window in real time;

[0030] The pressure in the shell ranges from 1000 Pa to 6 MPa.

[0031] At the same time, the present invention also provides a method for measuring the particle size of high back pressure PDPA atomization, based on the above-mentioned system for measuring the particle size of high back pressure PDPA atomization, which is special in that it includes the following steps:

[0032] Step 1, calibrating the parameters 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 inner wall of the quartz glass and the intersection point of the laser beam emitted by the laser emitting probe before refraction a1 , the distance x between the outer wall 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 transmitting 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 shell and the anti-fog collection bin through the window blowing unit, so that the pressure in the anti-fog collection bin 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 shell, the switch signal of the pneumatic valve and the air supply signal of the gas-liquid supply unit in real time;

[0035] Step 3, control the processor to make the laser emission probe emit a laser beam pair, use the automatic timing controller to control the gas-liquid supply unit to supply gas and liquid to the injector, and the gas-liquid mixture is atomized by 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, and use the automatic timing controller 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, and calculates 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 in the shell through the pressure p in 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, the angle θ' between the laser beam pair after refraction and the relative refractive index n' of the atomized droplet-air under the target back pressure are calculated respectively. rel ; According to the x recorded in step 1 g 、x a1 、x a2 , i , 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 'And ψ' j ;

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

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

[0040]

[0041] 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 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 and the center line of the laser transmitting probe, and the geometric parameter β of the other receiver j The calculation method of β i The calculation method is the same as;

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

[0043]

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

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

[0046]

[0047] Among them, n a is the refractive index of air outside the shell;

[0048] 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 :

[0049]

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

[0051]

[0052] Among them, n g is the refractive index of quartz glass, x is the distance between the intersection of the laser beam and the receiving probe; the angle ψ' between the propagation direction of the scattered light signal received by another receiver after refraction and the scattering plane j The calculation method of ψ i ' is calculated in the same way.

[0053] Further, step 2 is specifically as follows: the pneumatic valve on the pneumatic valve exhaust pipe is first closed by the automatic timing controller, and then the first valve on the air supply branch is opened, and the air is filled into the shell and the anti-fog collection bin through the window blowing unit, so that the pressure in the anti-fog collection bin is gradually increased. 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, the high-speed data acquisition instrument is started to collect the pressure in the shell, the switch signals of the pneumatic valve and the first valve in real time;

[0054] Step 3 specifically includes: controlling the processor to make the laser emitting probe emit a laser beam pair, using an automatic timing controller to open the second valve on the gas supply branch and the third valve on the liquid supply branch, and 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, the two receivers receive the scattered light signals respectively, 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, and the atomized particle size D of the gas-liquid mixture is calculated; at the same time, the high-speed data acquisition instrument collects the switch signal of the second valve on the gas supply branch, the gas supply pressure and flow, the switch signal 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 pneumatic valve is opened by the automatic timing controller, the first valve, the second valve and the third valve are closed, and the gas is discharged.

[0055] Beneficial effects of the present invention:

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

[0057] 2. In the present invention, since the anti-mist collection bin is provided with two first through holes, which are respectively connected to the normally open throat exhaust pipe and the pneumatic valve exhaust pipe, the back pressure and the blowing gas flow rate in the shell can be independently adjusted. The blowing gas flow rate of the window blowing unit can be adjusted by controlling the opening and closing of the pneumatic valve exhaust pipe. When the pneumatic valve exhaust pipe is opened, the exhaust area of ​​the anti-mist collection bin is large and the blowing gas flow rate is high, which plays a role in blowing away the quartz glass. When the pneumatic valve exhaust pipe is closed, the exhaust area of ​​the anti-mist collection bin is small, and the blowing gas acts as a booster. After the back pressure increases to the target pressure, the blowing gas flow rate decreases, which ensures the continuity of the blowing without affecting the atomization process of the injector. In the present invention, the window blowing unit is used in conjunction with the normally open throat exhaust pipe and the pneumatic valve exhaust pipe, which can blow away the liquid attached to the quartz glass, and at the same time, an air film can be formed to maintain the cleanliness of the quartz glass.

[0058] 3. In the present invention, the back pressure atomization device is modularized, the PDPA particle size measurement module is easy to disassemble and replace, the annular groove can better position the anti-fog collection bin, the crossbeam can prevent the partition from deforming, and the horizontal baffle and vertical baffle can reduce the force of the high-speed gas-liquid mixture on the back pressure atomization device. Under the joint action of the large-sized quartz glass window, the shell with an inner diameter of 200mm to 300mm, and the window blowing unit, the number and density of anti-fog droplets can be reduced, and the effective observation time can be extended.

[0059] 4. In the system for measuring the atomized particle size of high back pressure PDPA provided by the present invention, the three quartz glass windows strictly match the 120° first refraction optical path layout, so that the scattered light signal intensity 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 atomized particle size provided by the present invention, the synchronous measurement accuracy of the pressure data in the shell and the PDPA atomized droplet size can reach 1ms. The high back pressure PDPA atomized particle size measurement data is corrected by the method of the present invention, which can reduce the measurement system error caused by the refraction of quartz glass and the change of air density. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 is a schematic structural diagram of an embodiment of a system for measuring the atomized particle size of high back pressure PDPA according to the present invention;

[0062] Figure 2 Schematic diagram of the structure of the back pressure atomization device of the present invention;

[0063] Figure 3 is a structural schematic diagram of another perspective of an embodiment of the back-pressure atomization device of the present invention;

[0064] Figure 4 is a top view of an embodiment of a back-pressure atomization device of the present invention;

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

[0066] Figure 6 is a cross-sectional view of the back-mist collection chamber and the gas-liquid discharge chamber from another perspective in the embodiment of the back-pressure atomization device of the present invention;

[0067] Figure 7 2 is a schematic diagram of the structure of the partition in the embodiment of the back pressure atomization device of the present invention;

[0068] Figure 8 2 is a schematic structural diagram of a baffle assembly in an embodiment of a back-pressure atomization device of the present invention;

[0069] Fig. 9 Schematic diagram of the laser beam emission optical path of the laser emission probe in the embodiment of the method for measuring the atomized particle size of high back pressure PDPA of the present invention (the dotted line in the figure is the emission optical path of the laser beam before refraction, and the solid line is the emission optical path of the laser beam after refraction);

[0070] Fig.10 This is a schematic diagram of the receiving light path of the receiver in the receiving probe in an embodiment of the method for measuring the atomized particle size of high back pressure PDPA of the present invention (the dotted 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] Description of reference numerals:

[0072] 1-back pressure atomization device; 11-PDPA particle size measurement module; 111-housing; 112-mounting flange; 113-quartz glass window; 114-window blowing unit; 12-anti-fog collection chamber; 121-pressure measuring interface; 13-gas-liquid discharge chamber; 130-chamber; 131-partition; 132-normally open throat exhaust pipe; 133-pneumatic valve exhaust pipe; 134-liquid discharge pipe; 135-baffle assembly; 136-exhaust hole; 137-exhaust port; 138-throat; 139-chamber 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 transmitting probe; 32-receiving probe; 321-receiver; 33-processor; 34-software; 4-automatic timing controller; 5-delay 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-crossbeam; 17-blocking cover; 18-horizontal baffle; 19-vertical baffle; 20-arc notch. DETAILED DESCRIPTION

[0073] like Figure 2-Figure 8As shown, a back pressure atomization device includes a PDPA particle size measurement module 11, a back fog collection chamber 12 and a gas-liquid discharge chamber 13 arranged in sequence from top to bottom. Specifically, the PDPA particle size measurement module 11 includes 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°, 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, wherein the mounting flange 112 is used to install an injector, a quartz glass 8 is installed in each quartz glass window 113, and the blowing end of each window blowing unit 114 is close to the inner wall surface of the corresponding quartz glass 8. The upper end of the back fog collection chamber 12 is connected to the lower end flange of the housing 111, a pressure measuring interface 121 for connecting a pressure sensor is arranged on the side wall of the back fog collection chamber 12, and two first through holes 9 are arranged on the lower end surface of the back fog collection chamber 12. The gas-liquid discharge chamber 13 includes a chamber 130, a chamber seat 139, a partition 131, a normally open throat exhaust pipe 132, a pneumatic valve exhaust pipe 133, a liquid discharge pipe 134, two crossbeams 16 and two baffle assemblies 135, wherein the chamber 130 is arranged on the chamber seat 139, the partition 131 is arranged in the chamber 130, the partition 131 divides the chamber 130 into an upper chamber and a lower chamber, an exhaust port 137 is arranged on the side wall of the upper chamber, and installation notches are opened on two opposite side walls of the lower chamber. A central hole 14 and an annular groove 15 located at the outer edge of the central hole 14 are arranged in the middle of the partition 131, and 12 exhaust holes 136 with a diameter of 90 mm are evenly distributed along the edge of the partition 131, and the lower end of the anti-fog collection chamber 12 passes through the upper end surface of the upper chamber and is connected to the annular groove 15. Each baffle assembly 135 includes a baffle cover 17, a transverse baffle 18 and two vertical baffles 19. 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 extend 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 each transverse baffle 18 is provided with two arc-shaped notches 20. The four arc-shaped notches 20 of the two transverse baffles 18 are combined into two through holes. The transverse 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 out of the pneumatic valve exhaust pipe 133 and the throat 138, thereby achieving gas-liquid separation. The air inlet ends of the normally open throat exhaust pipe 132 and the pneumatic valve exhaust pipe 133 pass through two through holes and are respectively arranged at the center hole 14, and are respectively connected to the two first through holes 9 through flanges. 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, and the drain pipe 134 is arranged at the bottom of the chamber seat 139 and is connected to the second through hole 10.Two cross beams 16 are connected to the lower surface of the partition 131, and the two cross beams 16 are located on both sides of the installation gap. In this embodiment, the size of the quartz glass 8 is 115mm (L) × 145mm (W) × 45mm (H), the effective observation area is 85mm (L) × 100mm (W), the inner diameter of the shell 111 is 200mm ~ 300mm, and the exhaust port 137 is a rectangular exhaust port.

[0074] like Figure 1 As shown, this embodiment also provides a system for measuring the atomized particle size of high back pressure PDPA, including the above-mentioned back pressure atomization device 1, as well as a gas-liquid supply unit 2, a PDPA 3, an automatic timing controller 4, a delayed pulse signal generator 5, a high-speed data acquisition instrument 6, and a monitoring device 7. Specifically, the gas-liquid supply unit 2 includes a gas supply branch 21 and a liquid supply branch 22, the gas supply branch 21 is respectively connected to the air inlet ends of the three window blowing units 114, and is used to supply gas to the three window blowing units 114, and the gas supply branch 21 is used to communicate with the injector on the mounting flange 112, and supply gas to the injector on the mounting flange 112, and the liquid supply branch 22 is used to communicate with the injector, and supply liquid to the injector on the mounting flange 112.

[0075] PDPA3 includes 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 correspond to the positions of two quartz glass windows 113 respectively, and a 120° first refraction optical path layout is provided between the laser emitting probe 31 and the receiving probe 32. Three receivers 321 are arranged 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 respectively, and is used to control the laser emitting probe 31 to emit a laser beam pair, collect the scattered light signal received by the receiver 321, send the scattered light signal to the software 34, and receive the TTL trigger signal sent by the delayed pulse signal generator 5.

[0076] 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, and is used to switch 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.

[0077] 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 the flowmeter on the gas supply branch 21, the pressure sensor and the 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, 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 valves and the TTL trigger signal.

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

[0079] like Figure 9-10 As shown, this embodiment also provides a method for measuring the atomized particle size of high back pressure PDPA, based on the above-mentioned system for measuring the atomized particle size of high back pressure PDPA, specifically comprising the following steps:

[0080] Step 1, calibrating parameters of the back pressure atomization device 1 and the PDPA3;

[0081] 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 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; 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 i and ψ j ; Among them, the scattering plane is the plane formed by the optical axis of the laser transmitting probe 31 and the optical axis of the receiving probe 32.

[0082] Step 2, the pneumatic valve on the pneumatic valve exhaust pipe 133 is first closed through the automatic timing controller 4, so that the pneumatic valve exhaust pipe 133 is closed, and then the first valve 23 on the air supply branch 21 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 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 this time, the blowing air speed is reduced, but not 0, and the blowing air forms a layer of 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 switch signals of the pneumatic valve and the first valve 23 in real time, so as to check whether the pressure in the shell 111 is stable and whether the pneumatic valve and the first valve 23 are normally switched.

[0083] Step 3, the laser emitting probe 31 is made to emit a laser beam pair by controlling the processor 33, and the second valve 24 on the gas 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 atomized by the injector and then injected into the shell 111; 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 is used to control the delayed pulse signal generator 5 to send a TTL trigger signal to the processor 33, and the processor 33 collects the scattered light signal and sends it to the software 34, and the atomized particle size D of the gas-liquid mixture is calculated; at the same time, the high-speed data acquisition instrument 6 collects the gas supply signal in real time The switch signal of the second valve 24 on the branch 21, the gas supply pressure and flow, the switch signal of the third valve 25 on the liquid supply branch 22, the liquid supply pressure and flow, and the TTL trigger signal are used to check whether the second valve 24 and the third valve 25 are normally switched, whether the gas-liquid supply pressure and the gas-liquid flow are consistent, and whether the TTL trigger signal is effectively recorded; finally, the pneumatic valve on the pneumatic valve 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 to discharge the gas in the anti-fog collection bin 12. At this time, the blowing speed is increased, and the window blowing unit 114 blows the quartz glass 8 strongly to blow away the droplets attached to the quartz glass 8. Among them, the TTL trigger signal is a synchronization signal of the pressure data in the housing 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] 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 np 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.

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

[0087]

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

[0089] Step 5: Based on θ recorded in step 1 and n calculated in step 4, the angle θ' between the laser beam pair emitted by the laser emission probe 31 after refraction and the relative refractive index n' of the atomized droplet-air under the target back pressure are calculated respectively. rel ; According to x in step 1 g 、x a1 、x a2 , i , 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 'And ψ' j ; Specifically, θ' is calculated according to the following formula:

[0090]

[0091] Among them, n a is the refractive index of air outside the housing 111;

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

[0093]

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

[0095]

[0096] 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; ψ' j The calculation method of ψi ' is calculated in the same way.

[0097] Step 6: Use the θ' and n' calculated in step 5 rel , i ',ψ' j The D calculated in step 3 is corrected and updated to complete the measurement of the atomized particle size of the high back pressure PDPA.

[0098] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on 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 bin (12) is connected to the lower end of the housing (111), a pressure measuring interface (121) for connecting a pressure sensor is provided on the side wall of the anti-mist collection bin (12), and two first through holes (9) are provided on the lower end surface of the anti-mist collection bin (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 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 divide 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 installation 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 arranged on the upper end surface of the upper bin, and the pneumatic valve exhaust pipe (133) is arranged on the upper end surface of 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 arranged on the upper end surface ... 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 connected to 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 connected to 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 sprayed out of 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 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 bin (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 comprises two cross beams (16) arranged on the lower surface of the partition plate (131), and the two cross beams (16) are located on both sides of the installation notch; Each of the baffle components (135) comprises a baffle cover (17), a transverse baffle (18) and two vertical baffles (19); 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) extend 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); 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 exhaust pipe (133) pass through two through holes and are arranged at the center hole (14), and are connected to 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 115 mm×145 mm×45 mm, and the effective observation area is 85 mm×100 mm; The inner diameter of the housing (111) is 200 mm to 300 mm; The exhaust port (137) is a rectangular exhaust port; The partition plate (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 in that: It comprises the back pressure atomization device (1) as claimed in 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 instrument (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); the laser emitting probe (31) and the receiving probe (32) respectively correspond to the positions of two of the quartz glass windows (113); a primary refraction optical path layout of 120° is provided between the laser emitting probe (31) and the receiving probe (32); three receivers (321) are arranged on the receiving probe (32) for receiving scattered light signals; the processor (33) is respectively 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 delayed pulse signal generator (5) respectively, and is used to control the gas-liquid supply unit (2) to supply gas to the three window blowing units (114) or stop supplying gas, supply gas and liquid to the injector or stop supplying gas and liquid, switch 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 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 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 in real time.

5. The system for measuring the atomized particle size of high back pressure PDPA 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 switch 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 respectively electrically connected to 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 measuring interface (121), the pneumatic valve and the delayed pulse signal generator (5), and is used for real-time acquisition of the switch 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 switch 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 in the housing (111) ranges from 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 surface 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 an angle θ between the laser beam pair before refraction occurs; and an 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 close the pneumatic valve through the automatic timing controller (4), and then control the gas-liquid supply unit (2) to supply air to the window blowing unit (114), so that the air enters the housing (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 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, start the high-speed data acquisition instrument (6) 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 then injected into the housing (111); the laser beam pair irradiates the atomized droplets and scatters them, and the two receivers (321) receive the scattered light signals respectively, and the automatic timing controller (4) is used 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 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) to control the gas-liquid supply unit (2) to stop supplying gas to the window blowing unit (114) and the injector, and supplying liquid to the injector; Step 4, calculating the real-time air refractive index n in the housing (111) through 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, the angle θ' between the laser beam pair after refraction and the relative refractive index n' of the atomized droplet-air under the target back pressure are calculated respectively. rel ; According to the x recorded in step 1 g 、x a1 、x a2 , i , 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 'And ψ' j ; Step 6: Use the θ' and n' calculated in step 5 rel , i ',ψ' j The D calculated in step 3 is corrected and updated to complete the measurement of the atomized particle size of the high back pressure PDPA.

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 another receiver (321) j The calculation method of β i The calculation method is the same as; 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); and 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: firstly closing the pneumatic valve on the pneumatic valve type exhaust pipe (133) through the automatic timing controller (4), and then opening the first valve (23) on the air supply branch (21), so that air is filled into the housing (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 increases, and 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, 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), and injecting the gas-liquid mixture into the housing (111) after being atomized by the injector; the laser beam pair irradiates the atomized liquid droplets and scatters, and 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 of the second valve (24) on the gas supply branch (21), the gas supply pressure and flow rate, the switch signal of the third valve (25) on the liquid supply branch (22), the liquid supply pressure and flow rate, 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.

Images