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CN-121977159-A - Low-temperature pressure pulsation buffering device, and pressure stabilizing and conveying system and buffering method thereof

CN121977159ACN 121977159 ACN121977159 ACN 121977159ACN-121977159-A

Abstract

The invention relates to a low-temperature pressure pulsation buffer device, a pressure stabilizing and conveying system and a buffer method thereof, wherein a liquid phase buffer area and a gas phase buffer space positioned above the liquid phase buffer area are arranged in a buffer container body, and the liquid phase buffer area and the gas phase buffer space are separated by a gas-liquid interface without a solid diaphragm; the lower part of the buffer container body is provided with a low-temperature fluid inlet and a low-temperature fluid outlet which are both in the range of a liquid-phase buffer area, fluid does not pass through a gas-phase buffer space when entering and exiting, the gas-phase buffer space realizes energy storage and energy release by means of the compressibility of internal gas, pressure pulsation transmitted by the inlet is absorbed and attenuated by compression and expansion, and the buffer container body maintains a low-temperature working state by adopting a cold insulation structure or cold insulation arrangement. The invention adopts a diaphragm-free gas-liquid interface structure, avoids the problems of embrittlement failure and poor sealing reliability of the traditional diaphragm at low temperature, reduces the disturbance of the gas-liquid interface through the arrangement mode of the inlet liquid and the outlet liquid at the lower part, reduces the risks of gas entrainment and downstream flow vibration, and can provide stable low-temperature fluid supply for downstream loads.

Inventors

  • Yang Wubei
  • CHEN JIAHUA
  • ZHU WANQIAN
  • ZHENG YANPENG
  • FEI RONGJIE

Assignees

  • 中国科学院上海高等研究院

Dates

Publication Date
20260505
Application Date
20260407

Claims (10)

  1. 1. A low-temperature pressure pulsation buffering device comprises a buffering container body (1) and is characterized in that a liquid phase buffering area (4) and a gas phase buffering space (5) located above the liquid phase buffering area (4) are formed in the buffering container body (1), the liquid phase buffering area (4) and the gas phase buffering space (5) are separated through a gas-liquid interface without a physical diaphragm, a low-temperature fluid inlet (2) and a low-temperature fluid outlet (3) are arranged at the lower portion of the buffering container body (1), the low-temperature fluid inlet (2) and the low-temperature fluid outlet (3) are located in the range of the liquid phase buffering area (4), a fluid inlet and outlet path does not pass through the gas phase buffering space (5), the gas phase buffering space (5) can store energy and release energy according to the compressibility of internal gas, pressure pulsation transmitted by the low-temperature fluid inlet (2) is absorbed through compression and expansion of the gas, and the buffering container body (1) maintains a low-temperature working state through a cold keeping structure or a cold keeping arrangement.
  2. 2. The cryogenic pressure pulsation damping device according to claim 1, characterized in that a rectifying and energy dissipating structure (6) is arranged at the cryogenic fluid inlet (2) and positioned in the liquid phase buffer zone (4), and the rectifying and energy dissipating structure (6) is used for rectifying, decelerating and dissipating energy of cryogenic fluid entering the liquid phase buffer zone (4), weakening disturbance of inlet jet flow to a gas-liquid interface and inhibiting gas entrainment.
  3. 3. The low-temperature pressure pulsation damping device according to claim 2, characterized in that the rectifying and energy dissipating structure (6) is one or a combination of a plurality of porous plates, porous metal pieces, honeycomb rectifying pieces, diffusion structures or multi-stage orifice plates.
  4. 4. The low-temperature pressure pulsation damping device according to claim 1, wherein the damping container body (1) is a closed pressure-bearing vertical cylindrical shell, the upper part of the damping container body is of a closed structure, and no elastic diaphragm component is arranged inside the damping container body (1).
  5. 5. The low-temperature pressure pulsation damper according to claim 1, wherein the low-temperature fluid inlet (2) adopts a low-level layout structure, and the inlet opening is arranged below the normal working liquid level, so that the low-temperature fluid finishes feeding in the liquid phase area, the low-temperature fluid outlet (3) and the low-temperature fluid inlet (2) are mutually staggered in the circumferential direction or the horizontal direction, and the opening position of the low-temperature fluid outlet (3) is always below the normal working liquid level.
  6. 6. The low-temperature pressure pulsation damper according to claim 1, wherein the cold insulation structure or the cold insulation arrangement is a double-shell vacuum sandwich structure, an external normal-pressure liquid nitrogen bath immersion arrangement or a combination of the two, and a multi-layer heat insulation member, a radiation protection screen or a heat bridge blocking structure is further arranged in the vacuum sandwich structure for reducing external heat invasion.
  7. 7. The low-temperature pressure pulsation damping device according to claim 1, wherein vapor formed by volatilization of the low-temperature fluid naturally exists in the gas-phase damping space (5), and gas which is not condensed at the whole working temperature is filled when the working condition is needed, so as to stably provide a compressible damping effect.
  8. 8. A low-temperature fluid steady-pressure conveying system, which is characterized by comprising a low-temperature fluid supply device (11), an upstream connecting pipeline (12), a downstream connecting pipeline (13), a downstream load (14) and the low-temperature pressure pulsation damping device (10) according to any one of claims 1 to 7, wherein the low-temperature fluid supply device (11) is connected with a low-temperature fluid inlet (2) of the low-temperature pressure pulsation damping device (10) through the upstream connecting pipeline (12), and a low-temperature fluid outlet (3) of the low-temperature pressure pulsation damping device (10) is connected with the downstream load (14) through the downstream connecting pipeline (13).
  9. 9. The cryogenic fluid regulated delivery system of claim 8, wherein the cryogenic pressure pulsation damper (10) is disposed in series between the cryogenic fluid supply and the downstream load, the cryogenic fluid flowing from the cryogenic fluid supply to the downstream load along a continuous liquid phase delivery path during normal operation, the vapor phase buffer space not constituting a continuous product gas output path.
  10. 10. The low-temperature pressure pulsation buffering method is characterized in that the low-temperature pressure pulsation buffering device (10) according to any one of claims 1 to 7 is adopted, the low-temperature pressure pulsation buffering device (10) is connected in series between a low-temperature fluid supply device (11) and a downstream load (14) to form a continuous conveying passage, a cold insulation structure or cold insulation arrangement is used for maintaining the device in a low-temperature fluid working temperature area to ensure stable internal fluid state, low-temperature fluid enters a liquid-phase buffering area (4) through a low-temperature fluid inlet (2), pressure pulsation is transmitted to a gas-phase buffering space (5) through a gas-liquid interface, energy storage and energy release are achieved by utilizing the compressibility of gas in the gas-phase buffering space (5), the pressure pulsation is absorbed and attenuated, and the low-temperature fluid after pressure stabilization is output to the downstream load (14) through a low-temperature fluid outlet (3) to avoid downstream propagation of the pressure pulsation.

Description

Low-temperature pressure pulsation buffering device, and pressure stabilizing and conveying system and buffering method thereof Technical Field The invention relates to low-temperature engineering and low-temperature fluid transportation, in particular to a low-temperature pressure pulsation buffering device, a pressure stabilizing and conveying system and a buffering method thereof. Background In synchrotron radiation beam lines, cryocooling circuits, precision instrument thermal management systems, and other devices that use cryogenic fluids such as liquid nitrogen, it is often necessary to use a cryopump to circulate the cryogenic fluid to remove heat from the downstream load. In the running process of the system, the pump outlet pressure can generate periodic pressure pulsation mainly comprising shaft frequency, blade passing frequency and harmonic waves thereof under the influence of dynamic and static interference between the impeller and a static part of the low-temperature pump, fluctuation of rotating speed, local unsteady flow in a flow passage and other factors. When the pressure pulsation propagates to a downstream load along the low-temperature conveying pipeline, periodic pressure disturbance and flow fluctuation are formed at the load end, and the pressure pulsation is easy to further induce the problems of flow-induced vibration, local heat exchange fluctuation, temperature fluctuation, mechanical response amplification and the like in the application scenes with high stability requirements such as synchronous radiation monochromator cooling, ultra-precise low-temperature heat exchange, low-temperature test platform liquid supply and the like, so that the operation stability and the use effect of the system are finally affected. In order to restrain pressure pulsation generated by a pump source, a diaphragm type pulsation damper or an accumulator is commonly adopted in the existing fluid conveying system to realize pulsation absorption and pressure stabilization, and the device generally isolates internal buffer gas and pipeline fluid from each other by means of an elastic diaphragm and realizes attenuation of pressure pulsation by utilizing compressibility of the gas. However, most of diaphragms adopted by the conventional pulsation dampers are made of high polymer materials such as rubber and polymers, the applicable temperature range is concentrated in a normal temperature-middle low temperature range, and the extremely low temperature working condition of a liquid nitrogen temperature range is difficult to bear. In an ultralow temperature environment, the diaphragm material is easy to generate low-temperature embrittlement, elasticity loss, sealing failure and fatigue damage, long-term reliable work cannot be ensured, and the problems of gas-liquid communication, medium pollution, gas leakage and the like can be caused by diaphragm damage, so that the pulsation buffering function is completely lost. If a simple large-volume container is adopted as a buffer structure, the pulsation propagation intensity can be reduced to a certain extent by means of the volume effect, but the problem of unreasonable flow path design often exists, and inlet high-speed fluid is easy to directly impact an internal gas-liquid interface, so that the interface is severely fluctuated, gas is entrained and secondarily disturbed, and the buffer effect is obviously reduced. Meanwhile, the simple structure is not provided with special cold insulation measures aiming at extremely low temperature working conditions, external heat invasion easily causes low-temperature fluid to be heated and boiled, temperature fluctuation and internal pressure state instability, and pulsation inhibition capability is further weakened. Disclosure of Invention The invention aims to solve the problems that in the existing low-temperature fluid pulsation buffer device, a diaphragm is easy to embrittle and lose efficacy in a liquid nitrogen temperature region, an inlet jet flow is easy to disturb a gas-liquid interface, so that gas entrainment and flow-induced vibration risks are high. The low-temperature pressure pulsation buffering device comprises a buffering container body, wherein a liquid phase buffering area and a gas phase buffering space positioned above the liquid phase buffering area are formed in the buffering container body, the liquid phase buffering area and the gas phase buffering space are separated by a gas-liquid interface without a physical diaphragm, a low-temperature fluid inlet and a low-temperature fluid outlet are arranged at the lower part of the buffering container body, the low-temperature fluid inlet and the low-temperature fluid outlet are both positioned in the range of the liquid phase buffering area, a fluid inlet and outlet path does not pass through the gas phase buffering space, the gas phase buffering space realizes energy storage and energy release by virtue of the compressibility of internal gas, pres