Gas turbine flowmeter

Abstract

The invention relates to the technical field of flow measurement, in particular to a gas turbine flowmeter which comprises a shell, a front flow guide body (1), a rear flow guide body (3) and a machine core assembly (2) arranged between the front flow guide body and the rear flow guide body are arranged in the shell, and the machine core assembly (2) comprises a rotating shaft (21), a turbine rotor arranged on the rotating shaft (21) in a sleeving mode and a bearing set. The turbine rotor is arranged at the end, close to the front flow guide body (1), of the rotating shaft (21) in a sleeving mode and can rotate around the rotating shaft (21) in the shell. The turbine rotor comprises a hub and 4-10 blades (24) evenly distributed in the circumferential direction of the hub, the attack angle of the front edge of each blade (24) ranges from 15 degrees to 25 degrees, the rear edge of each blade (24) is of a gradually-shrunk bionic airfoil structure, the front edge of each blade (24) is thicker than the rear edge of each blade (24), and a wear-resistant coating layer is arranged from the front edge of each blade (24) to the maximum thickness position. Through the optimal design of the blade, the technical problems of blade abrasion and high noise in the prior art are solved.

Description

Technical Field

[0001] The invention relates to the technical field of flow measurement, and in particular to a gas turbine flowmeter. Background Art

[0002] The gas turbine flowmeter is a flow measurement instrument widely used in the fields of petroleum, natural gas, chemical industry, pharmaceutical industry, etc., and performs particularly well in the measurement of gas flow. The core component of the gas turbine flowmeter is the turbine rotor. When the gas flows through the flowmeter, the kinetic energy of the gas causes the turbine rotor to rotate, and the speed of the turbine rotor is proportional to the gas flow rate. The flowmeter is equipped with a sensor that can monitor the speed of the turbine in real time and convert it into an electrical signal, which is ultimately displayed as a flow value.

[0003] In practical applications, gas turbine flowmeters may encounter various challenges, especially in the process of transporting gas through pipelines. If the gas contains suspended particles or corrosive chemical components, when the turbine rotor rotates, the leading edge of the blade will be the first to collide with the corrosive chemical components or particles in the gas. This is the main cause of leading edge corrosion, and leading edge corrosion of the blade will greatly affect the operation of the turbine flowmeter and the accuracy of the flowmeter. At the same time, when the traditional spiral turbine rotor rotates, it is disturbed by the gas flow field, which is prone to produce wake vortices, increase pressure drop and cause vibration noise. The existence of the above problems will prevent the gas turbine flowmeter from working properly, thereby affecting its measurement accuracy and scope of application. Being in this abnormal working state for a long time will not only reduce the performance of the gas turbine flowmeter, but also shorten its service life, bringing additional maintenance and replacement costs to users. Summary of the invention

[0004] The invention provides a gas turbine flowmeter to solve the technical problems of blade wear and high noise in the gas turbine flowmeter in the prior art.

[0005] In order to solve the above problems, the present invention provides a gas turbine flowmeter, which adopts the following technical solutions: A gas turbine flowmeter comprises a shell, wherein a leading fluid, a trailing fluid and a core assembly arranged between the leading and trailing fluids are arranged in the shell, wherein the core assembly comprises a rotating shaft, a turbine rotor sleeved on the rotating shaft and a bearing group, wherein the turbine rotor is sleeved on one end of the rotating shaft close to the leading fluid and can rotate around the rotating shaft inside the shell; the turbine rotor comprises a hub, 4-10 blades evenly distributed along the circumference of the hub, the attack angle of the leading edge of the blade is 15°-25°, the trailing edge adopts a tapered bionic airfoil structure, the leading edge of the blade is thicker than the trailing edge, and a wear-resistant coating layer is provided from the leading edge of the blade to the maximum thickness.

[0006] Through a large number of experiments and studies, the inventors found that this range of angles of attack can make the gas generate appropriate lift and resistance when flowing through the blades, thereby more efficiently driving the turbine rotor to rotate and reducing the turbulence and resistance of the gas; the tapered bionic airfoil structure can effectively improve the flow characteristics of the gas at the trailing edge of the blade, reduce the separation of airflow and the generation of vortices, reduce flow resistance, improve the stability and uniformity of gas flow, and thus improve the measurement accuracy and reliability of the flow meter. The thicker leading edge of the blade can better withstand the impact of the gas, while the thinner trailing edge helps to reduce flow resistance. At the same time, the setting of the wear-resistant coating layer effectively improves the wear resistance of the blade, especially when the gas contains impurities such as suspended particles, it can reduce the wear of the blade and extend the service life of the blade, which means that the flow meter does not need to frequently replace the blades during long-term use, reducing maintenance costs and downtime, and improving the reliability and operating efficiency of the equipment.

[0007] The above-mentioned setting enables the gas to drive the turbine rotor to rotate more stably and efficiently when flowing through the turbine rotor, reducing the turbulence and energy loss of the gas flow, thereby improving the accuracy and reliability of the flow meter in measuring gas flow, and providing more reliable data support for industrial production and trade settlement.

[0008] As a preferred technical solution of the present invention, the wear-resistant coating layer is a tungsten carbide coating or a diamond-like carbon coating. This setting can significantly enhance the wear resistance and corrosion resistance of the turbine rotor blades, extend the service life of the turbine rotor blades, reduce the accuracy drop and failure risk caused by wear, thereby improving the measurement accuracy and ensuring that the flow meter can provide accurate and reliable measurement results throughout its life cycle.

[0009] As a preferred technical solution of the present invention, the wear-resistant coating layer has a thickness of 50-200 μm. The thickness of 50-200 μm can effectively resist the erosion of the blade surface by suspended particles and corrosive chemical components in the gas, ensuring that the coating can still maintain good wear resistance and corrosion resistance after long-term use. At the same time, it will not significantly increase the weight of the blade or change its aerodynamic characteristics, thereby ensuring that the rotation performance and measurement accuracy of the turbine rotor are not affected.

[0010] As a preferred technical solution of the present invention, the hub and blades of the turbine rotor are welded together by robot automatic argon arc welding.

[0011] As a preferred technical solution of the present invention, the turbine rotor is made of 17-4PH precipitation hardened stainless steel and is subjected to low-temperature ion nitriding treatment.

[0012] 17-4PH precipitation hardened stainless steel has excellent mechanical properties, including high strength, high hardness and good corrosion resistance, and can maintain stable performance in harsh industrial environments. The turbine rotor made of 17-4PH precipitation hardened stainless steel is treated with low-temperature ion nitriding to form a hard nitride layer on the surface of the turbine rotor, which significantly improves the surface hardness and wear resistance of the turbine rotor. This treatment method not only enhances the wear resistance of the blades, but also improves its fatigue resistance; and nitriding treatment can further improve the corrosion resistance of the material, especially in an environment containing corrosive gases, extending the service life of the turbine rotor.

[0013] Most importantly, the low-temperature ion nitriding treatment does not cause significant volume expansion or deformation, ensuring the dimensional accuracy and dynamic balancing performance of the turbine rotor, thereby ensuring that the measurement accuracy of the flow meter is not affected.

[0014] As a preferred technical solution of the present invention, the movement assembly also includes a movement, the movement sleeve is arranged on a bearing group, the bearing group includes two bearings and a sealed cavity, the sealed cavity is located between the two bearings, and the sealed cavity is composed of a closed chamber formed between the two bearings, the rotating shaft, and the movement; the sealed cavity is connected to the oil pump through a pipeline. The setting of the sealed cavity not only ensures the normal operation of the bearing, but also effectively prevents the invasion of external impurities and moisture, thereby improving the reliability and durability of the entire movement assembly. The oil pump transports the lubricating oil to the sealed cavity through a pipeline, and the lubricating oil forms an oil film in the sealed cavity, surrounding the rotating shaft and the bearing, and plays a role in lubrication and cooling.

[0015] As a more preferred technical solution of the present invention, the bearing is a jewel bearing or a ceramic ball bearing. Jewel bearings and ceramic ball bearings can maintain stable mechanical properties in high and low temperature environments, and will not undergo thermal expansion or contraction like metal bearings, thereby ensuring the precise operation of the movement components under different temperature conditions. At the same time, it also has the advantages of high precision, low friction, corrosion resistance and long life. The setting of the bearing using jewel bearings or ceramic ball bearings can significantly improve the performance and reliability of the gas turbine flowmeter, and is suitable for long-term stable operation under various complex working conditions.

[0016] As a preferred technical solution of the present invention, the movement assembly also includes a movement, the movement sleeve is arranged on the bearing group, the bearing group includes a magnetic suspension bearing group and an inert gas sealing chamber, the inert gas sealing chamber surrounds the magnetic suspension bearing group, and the inert gas sealing chamber is circulated with the main air flow channel through a pipeline. The inert gas sealing chamber surrounds the magnetic suspension bearing group to form a closed environment to prevent external pollutants from entering the bearing area. Filling the sealed chamber with an inert gas (such as helium, argon, etc.) can effectively isolate oxygen and other gases that may corrode or oxidize internal components, further improving the durability and reliability of the bearing and the movement. The inert gas sealing chamber is connected to the main air flow channel through a pipeline to ensure that the inert gas in the sealed chamber can be continuously circulated and renewed to maintain a stable internal environment; and this setting helps to maintain the pressure balance in the sealed chamber and prevent external pollutants from entering, while also taking away heat, playing a cooling role, and ensuring the stable operation of the system.

[0017] As a preferred technical solution of the present invention, a one-way valve or a pressure differential control valve is provided in the pipeline. This setting can significantly enhance the sealing performance of the sealing cavity and ensure the stability and cleanliness of the internal environment; by effectively preventing pollutants from entering and optimizing the internal conditions, these two valves can extend the service life of the bearing group and reduce maintenance requirements.

[0018] The one-way valve ensures that gas or liquid can only flow in one direction to prevent backflow. This is particularly important in the circulation between the sealed cavity and the pipeline, and can prevent external pollutants from flowing back into the sealed cavity through the pipeline. The one-way valve can effectively protect internal components from external pressure fluctuations and maintain the stability and safety of the system.

[0019] The differential pressure control valve can automatically adjust the valve opening according to the pressure difference inside and outside the seal chamber to ensure that the pressure inside the seal chamber remains within the set range. This helps to maintain a stable circulation of the medium and prevent problems caused by excessively high or low pressure; by accurately controlling the pressure difference, the differential pressure control valve can optimize the medium flow and cooling effect, further improving the operating efficiency and reliability of the bearing group.

[0020] As a preferred technical solution of the present invention, an inspection slot is provided on the top of the shell for observing the condition of the turbine rotor in the shell, and the inspection slot is fitted with a cover. The inspection slot allows the operator to directly observe the operating conditions of the turbine rotor and other key components in the shell, and to promptly discover potential problems. Inspections can be carried out without completely disassembling the equipment, which simplifies the maintenance process and saves time and cost. The cover is fitted with the inspection slot to ensure good sealing when no inspection is being carried out, preventing external contaminants from entering the shell. The provision of the inspection slot and the cover can significantly improve the maintainability and safety of the gas turbine flowmeter, and is suitable for long-term stable operation under various complex working conditions.

[0021] As a more preferred technical solution of the present invention, the cover is a transparent cover, and a sealing ring is provided on the edge of the cover. The transparent cover allows the operator to directly observe the operating conditions of the turbine rotor and other key components in the casing without opening the cover, thereby ensuring the normal operation of the equipment. Moreover, it is not necessary to frequently open the cover for inspection, thereby reducing the potential risks and maintenance time caused by opening and closing the cover. The sealing ring is installed on the edge of the cover to ensure a tight seal between the cover and the inspection slot, prevent external pollutants (such as dust, moisture, etc.) from entering the casing, and keep the internal environment clean and stable. The sealing ring can effectively prevent gas or liquid from leaking from the gap between the cover and the inspection slot, thereby ensuring the air tightness and water tightness of the system.

[0022] The beneficial effects are: 1. The present invention sets the leading edge attack angle of the turbine rotor blade to 15°-25°, and adopts a tapered bionic airfoil structure at the trailing edge, so that the blade can generate appropriate lift and drag, efficiently drive the turbine rotor to rotate stably, reduce gas turbulence, reduce energy loss, significantly improve the performance of the gas turbine flowmeter and reduce the flowmeter noise.

[0023] 2. The present invention uses a wear-resistant and corrosion-resistant 17-4PH precipitation hardened stainless steel turbine rotor, and forms a hard nitride layer on the surface of the turbine rotor through low-temperature ion nitriding treatment, which significantly improves the surface hardness and wear resistance of the turbine rotor. This treatment method not only enhances the wear resistance of the turbine rotor blades, but also improves its fatigue resistance; and the nitriding treatment can further improve the corrosion resistance of the material, especially in an environment containing corrosive gases, and prolongs the service life of the turbine rotor. Most importantly, the low-temperature ion nitriding treatment does not cause obvious volume expansion or deformation, ensuring the dimensional accuracy and dynamic balance performance of the turbine rotor, thereby ensuring that the measurement accuracy of the flowmeter is not affected.

[0024] 3. In terms of the bearing group, the present invention adopts a high-precision, low-friction bearing design, such as a magnetic bearing or adding a lubricating oil delivery pipeline to the rolling bearing. These settings can reduce bearing wear and sticking, and ensure the stability and reliability of the gas turbine flowmeter during long-term operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the side structure of Example 1 of the present invention; Figure 2 for Figure 1 Cross-sectional view along AA direction; Figure 3 for Figure 2 Enlarged view of middle B; Figure 4 for Figure 2Enlarged view of middle C; Figure 5 for Figure 2 Schematic diagram of the structure of the middle blade.

[0026] Description of reference numerals: 1. Leading fluid; 2. Movement assembly; 21. Rotating shaft; 22. Bearing; 23. Sealing chamber; 24. Blade; 3. Rear guiding fluid; 4. Magnetic sensor; 5. Pressure sensor; 6. Temperature sensor; 7. Oil pump; 8. One-way valve. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Those skilled in the art should know that the embodiments described below are part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0028] Any number of elements in the drawings is for illustration and not limitation, and any naming is for distinction only and does not have any limiting meaning.

[0029] The principle and spirit of the present invention are explained in detail below with reference to several representative embodiments of the present invention.

[0030] Embodiment 1: like Figure 1-2 A gas turbine flowmeter shown in 4 comprises a housing and an intelligent flow totalizer, wherein a leading fluid 1, a core assembly 2, a trailing fluid 3 and a sensor are arranged in the housing, wherein the leading fluid 1 and the trailing fluid 3 are respectively arranged at the front and rear ends of the housing, and are used to guide the airflow to smoothly enter and flow out of the flowmeter; the core assembly 2 is arranged between the leading fluid 1 and the trailing fluid 3; the core assembly 2 comprises a rotating shaft 21, a turbine rotor, a bearing group and a core, wherein the rotating shaft 21 is arranged in the middle of the housing and arranged along the axis of the housing, the bearing group and the turbine rotor are sleeved on the rotating shaft 21, the bearing group is coaxially connected to the turbine rotor, and the core is nested on the bearing group; the turbine rotor is fixedly arranged at one end of the core assembly 2 near the leading fluid 1 through the rotating shaft 21, and can be rotatably connected inside the housing, the turbine rotor is the core component of the flowmeter, and is responsible for converting the kinetic energy of the gas into mechanical energy (i.e., the rotation speed); the sensor is electrically connected to the intelligent flow totalizer; the intelligent flow totalizer is fixedly installed above the housing, and the intelligent flow totalizer directly displays the volume flow of the gas in the housing by receiving and processing the signal from the sensor.

[0031] The turbine rotor includes a hub and 4-10 blades 24 evenly distributed along the circumference of the hub. Figure 5As shown, the angle of attack of the leading edge of blade 24 is 15°, the trailing edge of blade 24 adopts a tapered bionic airfoil structure, the leading edge of blade 24 is thicker than the trailing edge, and a wear-resistant coating is provided from the leading edge of blade 24 to the maximum thickness. The wear-resistant coating is a tungsten carbide coating or a diamond-like coating, the thickness of the wear-resistant coating is 50μm, and the surface roughness Ra≤0.8μm. The turbine rotor is made of 17-4PH precipitation hardened stainless steel, the hub and blade 24 are automatically welded by a robot, and are treated with low-temperature ion nitriding, the surface hardness is ≥1000HV, and the core hardness is maintained at HRC30-35. The hub and blade 24 are processed more closely through argon arc welding, and the degree of fit is higher.

[0032] Of course, in other embodiments, the angle of attack of the leading edge of the blade 24 may also be any angle within the range of 15°-25°, such as 18°, 20°, 22°, 25°, etc. The thickness of the wear-resistant coating layer is any thickness within the range of 50-200 μm, such as 60, 80, 100, 150, 180 or 200 μm. The surface roughness Ra may also be 0.7 μm, 0.5 μm, or 0.3 μm.

[0033] As the key core part of the gas turbine flowmeter, the bearing group will heat up and lose oil when it rotates at high speed, so it is necessary to lubricate the bearing group. Figure 2 As shown, the bearing group is arranged in the middle of the rotating shaft 21, and sealing covers are embedded at both ends of the bearing group. The bearing group includes two bearings 22 and a sealing cavity 23, and the sealing cavity 23 is located between the two bearings 22. The sealed cavity 23 is formed between the two bearings 22 and the rotating shaft 21 and the movement. The sealing cavity 23 can allow the lubricating oil between the bearings 22 to circulate mutually, ensuring that each bearing 22 can be fully lubricated, avoiding wear caused by lack of oil, and thus reducing the accuracy of the turbine flowmeter. The sealing cavity 23 is connected to the oil pump 7 through a pipeline.

[0034] A one-way valve 8 is provided in the pipeline to prevent fluid backflow and ensure that there is sufficient lubricating oil flowing in the bearing group. Figure 3 As shown, the one-way valve 8 includes a sleeve, a push rod, and a piston. A sealing ring is provided between the sleeve and the pipe wall for sealing. The push rod is provided inside the sleeve. A spring is provided between the push rod and the sleeve. The diameter of the push rod is smaller than the inner diameter of the sleeve. A piston is provided in front of the push rod. The piston is adapted to be installed with the front end of the sleeve. When the oil pump 7 is started, the push rod of the one-way valve 8 is pushed due to pressure, and the push rod drives the piston to leave the front end of the sleeve. The lubricating oil is entered into the sealing chamber 23, and the lubricating oil flows in the sealing chamber 23, thereby playing a role in lubricating the two bearings 22. When the oil pump 7 is turned off, the piston is pressed into the front end of the sleeve, and the front end of the sleeve is tightly sealed. At this time, the one-way valve 8 is closed, thereby stopping the oiling of the sealing chamber 23.

[0035] Of course, in other embodiments, the one-way valve 8 in the pipeline can also be set as a pressure differential control valve, and the sealed cavity 23 is connected to the external oil barrel through the pressure differential control valve. The pressure differential control valve is provided in the pipeline, and the valve opening can be automatically adjusted according to the pressure difference between the inside and outside of the sealed cavity 23 to ensure that the pressure in the sealed cavity 23 is maintained within the set range; and the pressure differential control valve can effectively prevent the leakage of lubricating oil, and at the same time ensure that the lubricating oil can flow under appropriate pressure to maintain the normal operation of the bearing group.

[0036] The bearing 22 adopts a jewel bearing or a ceramic ball bearing with good wear resistance. The jewel bearing is such as a ruby ​​bearing, a sapphire bearing, and a ceramic ball bearing, which has high roundness, good corrosion resistance, and good hardness.

[0037] Enhanced bearing wear resistance and good sealing design enable the flowmeter to operate stably under various working conditions and provide better measurement stability. The optimized bearing group and blade 24 fit closely, and the precise processing technology and high-quality materials reduce measurement errors and improve measurement accuracy.

[0038] The sensor includes a magnetic sensor 4, a pressure sensor 5 and a temperature sensor 6, and the magnetic sensor 4, the pressure sensor 5 and the temperature sensor 6 are all electrically connected to the intelligent flow totalizer. The magnetic sensor 4 is arranged in a position corresponding to the signal transmitting disk in the housing, and the signal transmitting disk is nested on the rotating shaft 21. The magnetic sensor 4 reads the pulse signal emitted by the signal transmitting disk, and the signal is amplified and shaped by the preamplifier, and the temperature signal detected by the temperature sensor 6 and the pressure detected by the pressure sensor 5 are simultaneously transmitted to the intelligent flow totalizer for processing, and the volume flow is directly displayed on the intelligent flow totalizer.

[0039] When the gas enters the turbine flowmeter, the leading fluid 1 in the shell rectifies the others. Since the blades 24 are at a certain angle to the gas flow direction, the turbine blades 24 generate a torque, and the turbine starts to rotate after overcoming the resistance torque and friction torque. After the torque is balanced, the speed is stable, and the turbine rotation speed is linearly related to the flow rate. The speed of the turbine rotor will be accurately measured by the magnetic sensor 4. The signal is amplified and shaped by the preamplifier, and the temperature signal detected by the temperature sensor 6 and the pressure detected by the pressure sensor 5 are simultaneously transmitted to the intelligent flow integrator for processing, thereby obtaining the instantaneous flow value.

[0040] As a preferred solution of this embodiment, an inspection slot is provided on the top of the housing, through which the condition of the housing, especially the turbine rotor, can be observed. A cover is mounted on the inspection slot, and the cover is adapted to be installed with the inspection slot. The cover is adapted to be installed with the inspection slot to ensure good sealing when no inspection is performed, and to prevent external contaminants from entering the housing. The cover can be quickly opened and closed when needed, without affecting the normal operation of the equipment.

[0041] More preferably, the cover may also be integrated with other safety features, such as a lock or a warning sign, which can effectively prevent unauthorized operation or accidental opening, further ensuring the safe operation and reliability of the equipment.

[0042] Regular inspection and maintenance can timely discover and solve minor problems, avoid major failures, and thus extend the service life of the equipment; and convenient and fast inspection methods improve maintenance efficiency, reduce downtime, and ensure efficient operation of the equipment. The use of a setting with an inspection slot and a cover can significantly improve the maintainability and safety of the gas turbine flowmeter, and is suitable for long-term stable operation under various complex working conditions.

[0043] In order to ensure the tightness of the assembly between the cover and the inspection slot, a sealing ring is provided on the edge of the cover. The sealing ring is installed on the edge of the cover to ensure a tight seal between the cover and the inspection slot, prevent external pollutants (such as dust, moisture, etc.) from entering the shell, and keep the internal environment clean and stable. The sealing ring can effectively prevent gas or liquid from leaking from the gap between the cover and the inspection slot, ensuring the air tightness and water tightness of the system.

[0044] In order to make maintenance more convenient, the cover is set as a transparent cover, so that the situation inside the shell can be observed without opening the cover. The transparent cover allows operators to directly observe the operating conditions of the turbine rotor and other key components in the shell without opening the cover, ensuring the normal operation of the equipment; inspections can be carried out without frequently opening the cover, reducing the potential risks and maintenance time caused by opening and closing the cover. The setting of the transparent cover makes daily inspections more convenient, reduces downtime and maintenance difficulties, and improves work efficiency.

[0045] Embodiment 2: The main difference between it and Example 1 is: In this embodiment, the bearing adopts a magnetic suspension bearing, and the bearing group includes a magnetic suspension bearing group and an inert gas sealing chamber. The inert gas sealing chamber surrounds the magnetic suspension bearing group, and the inert gas sealing chamber is connected to the main gas flow channel through the guide channel. The inert gas sealing chamber is connected to the external gas source through a pressure difference control valve. When it is detected that the concentration of particulate matter in the inert gas sealing chamber exceeds the threshold, a high-pressure nitrogen pulse purge is automatically triggered to always maintain the cleanliness of the inert gas sealing chamber.

[0046] The inert gas sealed chamber surrounds the magnetic bearing group, forming a closed environment to prevent external contaminants from entering the bearing area. Filling the sealed chamber with inert gas (such as helium, argon, etc.) can effectively isolate oxygen and other gases that may corrode or oxidize internal components, further improving the durability and reliability of the bearing and movement.

[0047] The inert gas sealed chamber circulates with the main gas flow channel through the guide channel to ensure that the inert gas in the sealed chamber can be continuously circulated and renewed to maintain a stable internal environment; and gas flow control helps to maintain the pressure balance in the sealed chamber and prevent external pollutants from entering, while also taking away heat and playing a cooling role to ensure stable operation of the system. The inert gas sealed chamber is connected to the external gas source through a pressure differential control valve, which can automatically adjust the valve opening according to the pressure difference inside and outside the sealed chamber to ensure that the pressure in the sealed chamber remains within the set range.

[0048] The sensor monitors the particle concentration in the sealed chamber in real time to ensure timely cleaning when necessary and maintain efficient operation of the system. When the particle concentration in the inert gas sealed chamber exceeds the threshold, the system will automatically trigger high-pressure nitrogen pulse purge to quickly remove impurities in the sealed chamber and always maintain the cleanliness of the inert gas sealed chamber.

[0049] The use of a magnetic bearing group and an inert gas sealed chamber, combined with a differential pressure control valve and a high-pressure nitrogen pulse purge function, can significantly improve the performance and reliability of the gas turbine flowmeter, and is suitable for long-term stable operation of the turbine flowmeter under various complex working conditions.

[0050] Of course, in other embodiments, the inert gas sealed chamber may also be connected to an external gas source via a one-way valve.

[0051] Embodiment 3: The main difference between it and Example 1 is: In this embodiment, the blade is arranged in a curved surface, and the cross section of the blade is a semicircular structure. The semicircular blade uses the concave surface as the leading edge of the rotation. This setting is mainly suitable for high-efficiency, low-torque application scenarios, but for some working environments that require high speed or high load.

[0052] This setting enables the impeller to achieve higher output efficiency at lower energy input. The semicircular blades use the concave surface as the rotating leading edge, which can capture and push the fluid more effectively during rotation, thereby providing more gas mass transfer with less torque. However, during the startup phase, due to the particularity of the concave surface structure, a larger initial resistance may be generated, resulting in a longer startup time or requiring a larger starting torque; at low speed or startup, the fluid dynamics may cause system instability and affect the overall performance of the equipment.

[0053] According to the above description of this specification, those skilled in the art may also understand that the terms used below, such as "upper", "lower", "front", "back", "middle" and other terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings of this specification, which are only for the purpose of facilitating the explanation of the scheme of the present invention and simplifying the description, rather than explicitly or implicitly indicating that the device or element involved must have the specific orientation, be constructed and operate in a specific orientation. Therefore, the above-mentioned orientation or positional relationship terms cannot be understood or interpreted as limitations on the scheme of the present invention.

Claims

1. A gas turbine flowmeter, comprising a housing, wherein a leading fluid (1), a trailing fluid (3) and a core assembly (2) arranged between the leading and trailing fluids are arranged in the housing, wherein the core assembly (2) comprises a rotating shaft (21), a turbine rotor sleeved on the rotating shaft (21) and a bearing assembly, wherein the turbine rotor is sleeved on one end of the rotating shaft (21) close to the leading fluid (1) and can rotate around the rotating shaft (21) inside the housing; characterized in that: The turbine rotor comprises a hub and 4-10 blades (24) evenly distributed along the circumference of the hub. The attack angle of the leading edge of the blade (24) is 15°-25°, and the trailing edge adopts a tapered bionic airfoil structure. The leading edge of the blade (24) is thicker than the trailing edge. A wear-resistant coating layer is provided from the leading edge of the blade (24) to the maximum thickness.

2. A gas turbine flowmeter as claimed in claim 1, characterized in that: The wear-resistant coating layer is a tungsten carbide coating or a diamond-like coating.

3. A gas turbine flowmeter as claimed in claim 1 or 2, characterized in that: The wear-resistant coating layer has a thickness of 50-200 μm.

4. A gas turbine flowmeter as claimed in claim 3, characterized in that: The turbine rotor is made of 17-4PH precipitation hardened stainless steel and is subjected to low temperature ion nitriding treatment.

5. A gas turbine flowmeter as claimed in claim 4, characterized in that: The movement assembly (2) also includes a movement, the movement sleeve is arranged on a bearing group, the bearing group includes two bearings (22) and a sealed cavity (23), the sealed cavity (23) is located between the two bearings (22), and the sealed cavity (23) is composed of a closed chamber formed between the two bearings (22), the rotating shaft (21) and the movement; the sealed cavity (23) is connected to the oil pump (7) through a pipeline.

6. A gas turbine flowmeter as claimed in claim 5, characterized in that: The bearing (22) is a jewel bearing or a ceramic ball bearing.

7. A gas turbine flowmeter as claimed in claim 4, characterized in that: The movement assembly (2) also includes a movement, the movement is sleeved on a bearing group, the bearing group includes a magnetic suspension bearing group and an inert gas sealing chamber (23), the inert gas sealing chamber (23) surrounds the magnetic suspension bearing group, and the inert gas sealing chamber (23) is in communication with a main air flow channel through a pipeline.

8. A gas turbine flowmeter as claimed in claim 6 or 7, characterized in that: A one-way valve (8) or a pressure difference control valve is arranged in the pipeline.

9. A gas turbine flowmeter as claimed in claim 8, characterized in that: An inspection slot is provided on the top of the shell to allow observation of the turbine rotor inside the shell, and the inspection slot is adapted to be equipped with a cover.

10. A gas turbine flowmeter as claimed in claim 9, characterized in that: The cover is a transparent cover, and a sealing ring is arranged at the edge of the cover.

Images