Gas supply device for controlling mass flow based on sonic venturi nozzle

Abstract

The invention provides a gas supply device for controlling mass flow based on a sonic venturi nozzle, and relates to the technical field of gas supply, the gas supply device comprises a pressure control unit, the input end of the pressure control unit is used for being connected with a gas source; the flow control unit comprises a digital valve, the digital valve comprises an air inlet collecting chamber, a venturi nozzle, an electromagnetic valve and an air outlet collecting chamber, the air inlet collecting chamber is connected with the output end of the pressure control unit, a plurality of communicating pipes are arranged between the air inlet collecting chamber and the air outlet collecting chamber, and each communicating pipe is provided with the venturi nozzle and the electromagnetic valve; the input end of the temperature control unit is connected with the gas outlet and collection chamber, and the output end of the temperature control unit is used for being connected with a gas consumption unit; the technical problem that high-pressure gas with stable pressure output and accurate mass flow output is difficult to obtain in the prior art is solved.

Description

Technical Field

[0001] This invention belongs to the field of gas supply technology, and more specifically, relates to a gas supply device based on controlling mass flow rate using a sonic venturi nozzle. Background Technology

[0002] With the rapid development of technology, the requirements for gas mass flow rate in gas and fluid-related research are becoming increasingly stringent. For example, wind tunnel systems require high-pressure gas with set pressure, flow rate, and temperature. However, achieving stable output of high-pressure gas pressure and mass flow rate remains a challenge. The pressure control unit's adjustment of high-pressure gas pressure exhibits fluctuations, which clearly hinders the attainment of stable high-pressure gas output. Furthermore, accurately outputting high-pressure gas with a stable mass flow rate is also a difficult problem in this field. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a gas supply device based on a sonic venturi nozzle to control mass flow rate, thereby solving the technical problem of obtaining stable pressure output and accurate mass flow rate output of high-pressure gas in existing technologies.

[0004] To achieve the above objectives, the present invention provides a gas supply device for controlling mass flow rate based on a sonic venturi nozzle, comprising: Pressure control unit; the input terminal of the pressure control unit is used to connect to the gas source. The flow control unit includes a digital valve, which includes an inlet air collection chamber, a venturi nozzle, a solenoid valve, and an outlet air collection chamber. The inlet air collection chamber is connected to the output end of the pressure control unit. Multiple connecting pipes are provided between the inlet air collection chamber and the outlet air collection chamber. Each connecting pipe is equipped with a venturi nozzle and a solenoid valve. The temperature control unit has its input end connected to the gas collection chamber and its output end connected to the gas consumption unit.

[0005] Optionally, the pressure control unit includes a first valve, a pre-filter, a second valve, and a pressure regulating assembly sequentially disposed on the main gas supply pipe.

[0006] Alternatively, the Venturi nozzle can be made of brass.

[0007] Optionally, the nozzle throat diameter error of the Venturi nozzle is ±5μm.

[0008] Optionally, the surface roughness of the inner flow channel of the Venturi nozzle is 0.8 μm.

[0009] Optionally, the connecting pipe is made of stainless steel.

[0010] Optionally, the surface roughness of the inner flow channel of the connecting pipe is 1.3 μm.

[0011] Optionally, the flow coefficient of the solenoid valve is matched with the nozzle throat diameter of its corresponding Venturi nozzle to ensure that the Venturi nozzle is in critical sonic condition within the working pressure range of the digital valve.

[0012] Optionally, the temperature control unit includes a heat exchanger, a flow meter, a venturi tube, a first post-filter, and a third valve, which are sequentially arranged on the main gas supply pipe.

[0013] Optionally, two pressure control unit, two flow control unit, and two temperature control unit are provided, and they are respectively installed on the first gas supply main pipe and the second gas supply main pipe in parallel.

[0014] This invention provides a gas supply device based on a sonic venturi nozzle for controlling mass flow rate. Its advantages are as follows: The gas supply device, based on a sonic venturi nozzle for controlling mass flow rate, has a pressure control unit, a flow control unit, and a temperature control unit sequentially installed on the main gas supply pipe. By controlling the pressure, flow rate, and temperature, it outputs gas at a set pressure, flow rate, and temperature for use as experimental gas in the test model. The flow control unit uses a digital valve for flow regulation. Gas passing through the pressure control unit enters the inlet gas collection chamber and then enters the outlet gas collection chamber through multiple connecting pipes in a multi-path manner. Venturi nozzles and solenoid valves are sequentially installed on the connecting pipes. The solenoid valves control the opening and closing of each connecting pipe, thereby... The mass flow rate of the gas output by the digital valve is adjusted. At the same time, the critical flow characteristics of the Venturi nozzle are utilized. When the gas passes through the critical flow nozzle, under the condition that the pressure ratio of the gas flow upstream and downstream of the nozzle reaches the set value, the nozzle throat forms a critical state, the gas flow reaches the maximum speed (local speed of sound), and the mass flow rate of the gas flowing through the nozzle also reaches the maximum. At this time, it is only related to the stagnation pressure and temperature at the nozzle inlet, and is not affected by the changes in the upstream and downstream states. Based on this characteristic of the Venturi nozzle, the mass flow rate of the gas output by the digital valve is stable and is not affected by the pressure fluctuations of the gas output by the upstream pressure control unit. It can stably and accurately output the set flow rate of gas, and achieve precise and stable high-pressure gas supply with a simple structure.

[0015] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0016] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the invention.

[0017] Fig. 1A schematic diagram of the pressure control unit of an air supply device based on a sonic venturi nozzle for controlling mass flow rate is shown according to an embodiment of the present invention.

[0018] Fig. 2 A schematic diagram of the flow control unit of an air supply device based on a sonic venturi nozzle for controlling mass flow rate is shown according to an embodiment of the present invention.

[0019] Fig. 3 A schematic diagram of the temperature control unit of a gas supply device based on a sonic venturi nozzle for controlling mass flow rate is shown according to an embodiment of the present invention.

[0020] Explanation of reference numerals in the attached figures: 1. Pressure control unit; 2. Flow control unit; 3. Digital valve; 4. Inlet air chamber; 5. Venturi nozzle; 6. Solenoid valve; 7. Outlet air chamber; 8. Temperature control unit; 9. First valve; 10. Pre-filter; 11. Second valve; 12. Pilot-operated pressure reducing valve; 13. Regulating valve; 14. Heat exchanger; 15. Flow meter; 16. Venturi tube; 17. First post-filter; 18. Third valve; 19. First main gas supply pipe; 20. Second main gas supply pipe; 21. High-pressure gas source main pipe; 22. Test model; 23. Auxiliary exhaust pipe; 24. Exhaust valve; 25. Silencer; 26. First pressure gauge; 7. First pressure transmitter; 28. Second pressure gauge; 29. ​​First temperature transmitter; 30. Second temperature transmitter; 31. Second pressure transmitter; 32. Third pressure gauge; 33. Fourth pressure gauge; 34. Third temperature transmitter; 35. Third pressure transmitter; 36. Fourth pressure transmitter; 37. Fourth temperature transmitter; 38. Fifth temperature transmitter; 39. Sixth temperature transmitter; 40. Second post-filter; 41. Fifth pressure transmitter; 42. Seventh temperature transmitter; 43. Eighth temperature transmitter; 44. Sixth pressure transmitter; 45. Connecting pipe; 46. Commissioning room; 47. Fourth valve. Detailed Implementation

[0021] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0022] like Figs. 1 to 3 As shown, the present invention provides a gas supply device for controlling mass flow rate based on a sonic venturi nozzle, comprising: Pressure control unit 1, the input terminal of pressure control unit 1 is used to connect to the gas source; The flow control unit 2 includes a digital valve 3, which includes an inlet air collection chamber 4, a Venturi nozzle 5, a solenoid valve 6, and an outlet air collection chamber 7. The inlet air collection chamber 4 is connected to the output end of the pressure control unit 1. Multiple connecting pipes are provided between the inlet air collection chamber 4 and the outlet air collection chamber 7. Each connecting pipe is equipped with a Venturi nozzle 5 and a solenoid valve 6. Temperature control unit 8, the input terminal of temperature control unit 8 is connected to the gas collection chamber 7, and the output terminal of temperature control unit 8 is used to connect to the gas consumption unit.

[0023] Specifically, to address the technical problem of obtaining stable pressure output and precise mass flow rate output of high-pressure gas in existing technologies, the gas supply device based on sonic venturi nozzle mass flow rate control provided by this invention has a pressure control unit 1, a flow control unit 2, and a temperature control unit 8 sequentially arranged on the main gas supply pipe. By controlling the pressure, flow rate, and temperature, it outputs gas with a set pressure, set flow rate, and set temperature as test gas, which is supplied to the test model 22. The flow control unit 2 uses a digital valve 3 for flow regulation. The gas passing through the pressure control unit 1 enters the inlet gas collection chamber 4, and then enters the outlet gas collection chamber 7 in a multi-path manner through multiple connecting pipes. Venturi nozzles 5 and solenoid valves 6 are sequentially arranged on the connecting pipes. The solenoid valves 6 control the various... The opening and closing of the connecting pipe regulates the mass flow rate of the gas output by the digital valve 3. Simultaneously, utilizing the critical flow characteristics of the Venturi nozzle 5, when the gas passes through the critical flow nozzle, under the condition that the pressure ratio of the airflow upstream and downstream of the nozzle reaches a set value, the nozzle throat forms a critical state, the airflow reaches its maximum speed (local speed of sound), and the mass flow rate of the gas flowing through the nozzle also reaches its maximum. At this time, it is only related to the stagnation pressure and temperature at the nozzle inlet, and is not affected by changes in the upstream and downstream states. Based on this characteristic of the Venturi nozzle 5, the mass flow rate of the gas output by the digital valve 3 is stable and is not affected by the pressure fluctuations of the gas output by the upstream pressure control unit 1. It can stably and accurately output the set flow rate of gas, achieving precise and stable high-pressure gas supply with a simple structure.

[0024] Optionally, the pressure control unit 1 includes a first valve 9, a pre-filter 10, a second valve 11, and a pressure regulating assembly sequentially disposed on the main gas supply pipe.

[0025] Specifically, the first valve 9 and the second valve 11 can control the opening and closing of the main gas supply pipe. The pre-filter 10 filters the incoming gas downstream of the first valve 9 before it performs pressure control, flow control and temperature control, thereby improving the cleanliness of the gas. The filtered gas is then regulated by the pressure regulating component to achieve pressure control.

[0026] In this embodiment, the pressure regulating assembly includes a pilot-operated pressure reducing valve 12 disposed on the main gas supply pipe and a regulating valve 13 connected to one side of it via a bypass.

[0027] Optionally, the Venturi nozzle 5 is made of brass.

[0028] Specifically, the nozzle throat diameter of the Venturi nozzle 5 and the number of Venturi nozzles 5 are determined according to the flow range and accuracy.

[0029] In this embodiment, the connecting pipe has 38 channels, which are connected in two rows between the inlet air collection chamber 4 and the outlet air collection chamber 7. The connection method of the connecting pipe allows for easy disassembly and reassembly of the solenoid valve 6 and the Venturi nozzle 5, which can facilitate the replacement of the solenoid valve 6 and the Venturi nozzle 5. By replacing the Venturi nozzle 5, the mass flow rate can also be adjusted.

[0030] Optionally, the nozzle throat diameter error of the Venturi nozzle 5 is ±5μm.

[0031] Optionally, the surface roughness of the inner flow channel of the Venturi nozzle 5 is 0.8 μm.

[0032] Optionally, the connecting pipe is made of stainless steel.

[0033] Optionally, the surface roughness of the inner flow channel of the connecting pipe is 1.3 μm.

[0034] Optionally, the flow coefficient of the solenoid valve 6 is matched with the nozzle throat diameter of its corresponding Venturi nozzle 5 to ensure that the Venturi nozzle 5 is in critical sonic condition within the working pressure range of the digital valve 3.

[0035] Specifically, the flow coefficient Kv of solenoid valve 6 must match the corresponding nozzle grate diameter. Solenoid valve 6 with a large flow coefficient should be selected first to ensure that the nozzle is in critical sonic condition within the working pressure range of digital valve 3. At the same time, the selection of solenoid valve 6 should take into account maintainability, and the number of specifications and models should not exceed 3.

[0036] Optionally, the temperature control unit 8 includes a heat exchanger 14, a flow meter 15, a venturi tube 16, a first post-filter 17, and a third valve 18, which are sequentially arranged on the gas supply main pipe.

[0037] Specifically, the heat exchanger 14 can input liquid and gas for heat exchange, thereby controlling the temperature of the gas. The temperature-controlled gas passes through the venturi tube 16, which is a redundant design for system flow measurement. It can be used as a backup for the digital valve flow measurement and can also be used as the raw data for error analysis. After that, the gas enters the first post-filter 17 for filtration so that clean gas with the set pressure, set flow rate and set temperature can be delivered to the test model 22.

[0038] In this embodiment, the first valve 9, the second valve 11, and the third valve 18 are all high-pressure ball valves.

[0039] Optionally, two pressure control unit 1, two flow control unit 2, and two temperature control unit 8 are provided, and are respectively arranged on the first gas supply main pipe 19 and the second gas supply main pipe 20 in parallel.

[0040] Specifically, the two gas supply pipes are arranged in parallel and connected to the same gas source. The gas source can be a high-pressure gas source pipe 21 connected to the two gas supply pipes. The two gas supply pipes form a flow control redundancy, and finally form a gas with a set pressure, set flow rate and set temperature for test use.

[0041] In this embodiment, as Figs. 1 to 3 As shown, Figs. 1 to 3 A schematic diagram of a complete gas supply device based on a sonic venturi nozzle for controlling mass flow rate is shown, which can be connected sequentially. An auxiliary exhaust pipe 23 and multiple auxiliary pipes are also connected to the main gas supply pipe. The auxiliary exhaust pipe 23 is equipped with an exhaust valve 24 and a silencer 25. The multiple auxiliary pipes are used to connect to measurement and control components. The pressure control unit 1 includes a first pressure gauge 26 and a first pressure transmitter 27 located upstream of the first valve 9, a second pressure gauge 28 located downstream of the pre-filter 10, and a first temperature transmitter 29 located downstream of the second valve 11. The flow control unit 2 includes a second temperature transmitter 30, a second pressure transmitter 31, and a third pressure gauge 32 located on the inlet gas chamber 4, and a fourth pressure gauge 33 and a third temperature transmitter located downstream of the digital valve 3. The device includes a third pressure transmitter 34, a third pressure transmitter 35, and a temperature control unit 8, which includes a fourth pressure transmitter 36 and a fourth temperature transmitter 37 located upstream of the heat exchanger 14, a fifth temperature transmitter 38 and a sixth temperature transmitter 39 located downstream of the heat exchanger 14, a fifth pressure transmitter 41, a seventh temperature transmitter 42 and an eighth temperature transmitter 43 located on the venturi tube 16, and a sixth pressure transmitter 44 located downstream of the venturi tube 16. A connecting pipe 45 connects the first gas supply main pipe 19 and the second gas supply main pipe 20. One end of the connecting pipe 45 is connected upstream of the third valve 18 on the first gas supply main pipe 19, and the other end of the connecting pipe 45 is used to connect to the commissioning room 46. A fourth valve 47 and a second post-filter 40 are sequentially installed on the connecting pipe 45.

[0042] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A gas supply device for controlling mass flow rate based on a sonic venturi nozzle, characterized in that, include: Pressure control unit; the input terminal of the pressure control unit is used to connect to the gas source. The flow control unit includes a digital valve, which includes an inlet air collection chamber, a venturi nozzle, a solenoid valve, and an outlet air collection chamber. The inlet air collection chamber is connected to the output end of the pressure control unit. Multiple connecting pipes are provided between the inlet air collection chamber and the outlet air collection chamber. Each connecting pipe is equipped with a venturi nozzle and a solenoid valve. The temperature control unit has its input end connected to the gas collection chamber and its output end connected to the gas consumption unit.

2. The gas supply device based on a sonic venturi nozzle for controlling mass flow rate according to claim 1, characterized in that, The pressure control unit includes a first valve, a pre-filter, a second valve, and a pressure regulating assembly, which are sequentially arranged on the main gas supply pipe.

3. The gas supply device based on controlling mass flow rate using a sonic venturi nozzle according to claim 1, characterized in that, The Venturi nozzle is made of brass.

4. The gas supply device based on a sonic venturi nozzle for controlling mass flow rate according to claim 1, characterized in that, The nozzle throat diameter error of the Venturi nozzle is ±5μm.

5. The gas supply device based on controlling mass flow rate using a sonic venturi nozzle according to claim 1, characterized in that, The surface roughness of the inner flow channel of the Venturi nozzle is 0.8 μm.

6. The gas supply device based on controlling mass flow rate using a sonic venturi nozzle according to claim 1, characterized in that, The connecting pipe is made of stainless steel.

7. The gas supply device based on a sonic venturi nozzle for controlling mass flow rate according to claim 1, characterized in that, The surface roughness of the inner flow channel of the connecting pipe is 1.3 μm.

8. The gas supply device for controlling mass flow rate based on a sonic venturi nozzle according to claim 1, characterized in that, The flow coefficient of the solenoid valve is matched with the nozzle throat diameter of its corresponding Venturi nozzle to ensure that the Venturi nozzle is in critical sonic condition within the working pressure range of the digital valve.

9. The gas supply device based on a sonic venturi nozzle for controlling mass flow rate according to claim 1, characterized in that, The temperature control unit includes a heat exchanger, a flow meter, a venturi tube, a first post-filter, and a third valve, which are sequentially arranged on the main gas supply pipe.

10. The gas supply device based on a sonic venturi nozzle for controlling mass flow rate according to claim 1, characterized in that, Two pressure control units, two flow control units, and two temperature control units are provided, and they are respectively installed on the first gas supply main pipe and the second gas supply main pipe, forming a parallel arrangement.

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