阅读说明：本技术 一种实现抑制低温管道压力波动的结构 (Structure for realizing suppression of low-temperature pipeline pressure fluctuation ) 是由 陈慧 杨鹏 胡露露 亓新 刘迎文 于 2020-03-06 设计创作，主要内容包括：一种实现抑制低温管道压力波动的结构,包括低温温控箱,通过制冷机提供冷量；在所述低温温控箱的核心腔体上通过低温管道与室温端稳定压力气源相连接；所述低温管道一端位于室温环境,一端位于低温环境,形成沿管道的轴向温度梯度分布,从而诱发低温温控箱核心腔体及管道内部的压力波动；低温管道上安装有抑制系统内部压力波动模块。稳定压力气源的工作介质通过低温管道进入低温温控箱的核心腔体,在整个系统中形成一个稳定的压力环境。本发明一方面解决低温管道中出现的热声震荡现象导致的系统漏热损失大以及压力测量失稳等问题,另一方面提供了一种可实现系统压力波动抑制的模块,其结构简单,易于实现,性能可靠。(A structure for realizing the suppression of low-temperature pipeline pressure fluctuation comprises a low-temperature control box, a refrigerating machine and a temperature control device, wherein the refrigerating machine is used for providing cold energy; the core cavity of the low-temperature control box is connected with a room-temperature end stable pressure air source through a low-temperature pipeline; one end of the low-temperature pipeline is positioned in a room temperature environment, and the other end of the low-temperature pipeline is positioned in a low-temperature environment, so that axial temperature gradient distribution along the pipeline is formed, and pressure fluctuation in a core cavity of the low-temperature control box and the pipeline is induced; and the low-temperature pipeline is provided with a module for suppressing the pressure fluctuation inside the system. The working medium of the stable pressure air source enters the core cavity of the low-temperature control box through the low-temperature pipeline, and a stable pressure environment is formed in the whole system. The invention solves the problems of large system heat leakage loss, pressure measurement instability and the like caused by the thermoacoustic oscillation phenomenon in a low-temperature pipeline on one hand, and provides a module capable of realizing system pressure fluctuation inhibition on the other hand, and the module is simple in structure, easy to realize and reliable in performance.)

1. A structure for realizing suppression of low-temperature pipeline pressure fluctuation is characterized in that: the system comprises a low-temperature control box (1) with a refrigerator (2), wherein a core cavity (3) of the low-temperature control box (1) is connected with a room-temperature-end stable-pressure air source (5) through a low-temperature pipeline (4), one end of the low-temperature pipeline (4) is located in a room-temperature environment, the other end of the low-temperature pipeline is located in a low-temperature environment, temperature gradient distribution along the axial direction of a pipe is formed, accordingly, pressure oscillation inside the system is induced, and a pressure fluctuation suppression module (6) is installed on the low-temperature pipeline (4) in the low-temperature control.

2. The structure for realizing suppression of pressure fluctuation in a cryogenic pipeline according to claim 1, wherein: the pressure fluctuation suppression module (6) adopts a dynamic dissipation impeller (7) and a sudden change structure (8) with inconsistent bidirectional resistance-capacitance to be connected in series to realize suppression of pressure fluctuation in the system.

3. The structure for realizing suppression of pressure fluctuation in a cryogenic pipeline according to claim 2, wherein: the impeller (7) is centrifugal, radial-flow or mixed-flow, and dynamic dissipation in the system is increased through different flow characteristics at two sides of the impeller, so that pressure fluctuation is reduced.

4. The structure for realizing suppression of pressure fluctuation in a cryogenic pipeline according to claim 2, wherein: the mutation structure (8) adopts a multi-layer uneven density fin structure (6.1).

5. The structure for realizing suppression of pressure fluctuation in a cryogenic pipeline according to claim 4, wherein: the shape of the fins (9) of the multi-layer uneven density fin structure (6.1) adopts a triangle, a ring or a rectangle.

6. The structure for realizing suppression of pressure fluctuation in a cryogenic pipeline according to claim 2, wherein: the mutation structure (8) adopts a gradually expanding or gradually contracting regulating element group (6.2).

7. The structure for realizing suppression of pressure fluctuation in a cryogenic pipeline according to claim 4 or 6, wherein: the structural size of the abrupt structure (8) is determined according to the pressure gradient formula (1) and the volume flow rate gradient formula (2) caused by the movement of the working medium in the structure to be minimum:

p is the pressure of the working medium, w is the frequency of oscillation of the working medium in the pipeline, l is the inductance per unit length, r_μImpedance per unit length, U the volume flow rate of the working medium flow, c the capacitance per unit length, r_kAnd g is a volume flow source term, i is an imaginary number unit, and the capacitance, the inductance and the impedance corresponding to the mutation structure can be obtained by minimizing the pressure gradient and the volume flow rate gradient generated when the working medium flows through the mutation structure, so that the structural parameters of the mutation structure (8) are reasonably distributed.

Technical Field

The invention relates to a structure for suppressing pipeline pressure fluctuation, in particular to a structure for suppressing low-temperature pipeline pressure fluctuation.

Background

Thermoacoustic oscillation phenomena are often generated in industrial equipment due to the influence of the system working environment or the equipment structure, particularly in cryogenic Engineering measurement and cryogenic liquid storage systems, the cryogenic pipeline may oscillate in the cryogenic pipeline due to the temperature gradient formed between the cold end and the hot end, however, the thermoacoustic oscillation phenomena are double-edged swords, and oscillation is mostly harmful in most occasions, particularly in cryogenic systems, on the one hand, oscillation increases heat leakage loss in the cryogenic pipeline system, causing misalignment of pressure measurement in the cryogenic environment, and on the other hand, oscillation seriously affects safe operation of experimental equipment, in cryogenic fluid cooling systems, such as those cooled by liquid helium or super-helium, severe pressure oscillation and temperature oscillation due to thermal disturbance or mechanical disturbance occur, if flexible, reliable and efficient suppression technology is not available, development of cryometrology etc. will be subject to Nucific and restrictive effects, and influences, at present, research on the phenomena and mechanism of thermal oscillation is focused on thermal oscillation and mechanical studies, H.F.Sminov et al (Smirnov H, thermal oscillation suppression technology, Bo. L. Calif there is not available, research on thermal oscillation of thermal oscillation in the thermal water, thermal oscillation, thermal shock et al, Journal, research on thermal shock et al.

Disclosure of Invention

The invention aims to solve the problems of large heat leakage loss of a system, instability of pressure measurement and the like caused by the thermoacoustic oscillation phenomenon in a low-temperature pipeline, and provides a structure for realizing the suppression of pressure fluctuation of the low-temperature pipeline, which has the advantages of simple structure, easiness in realization and reliable performance.

In order to achieve the purpose, the invention adopts the technical scheme that: the low-temperature control system comprises a low-temperature control box with a refrigerator, wherein a core cavity of the low-temperature control box is connected with a room-temperature end stable pressure air source through a low-temperature pipeline, one end of the low-temperature pipeline is located in a room-temperature environment, the other end of the low-temperature pipeline is located in a low-temperature environment, temperature gradient distribution along the axial direction of a pipe is formed, accordingly, pressure oscillation inside the system is induced, and a pressure fluctuation suppression module is installed on the low-temperature pipeline in the low-temperature.

The pressure fluctuation suppression module adopts a dynamic dissipation impeller and a sudden change structure with inconsistent bidirectional resistance-capacitance to be connected in series to suppress pressure fluctuation in the system.

The impeller is centrifugal, radial-flow or mixed-flow, and dynamic dissipation in the system is increased through different flow characteristics at two sides of the impeller, so that pressure fluctuation is reduced.

The abrupt structure adopts the uneven fin structure of multilayer density.

The shape of the fin of the multi-layer uneven density fin structure is triangular, annular or rectangular.

The mutation structure adopts a gradually expanding or gradually contracting type regulating element group.

The structural size of the abrupt structure is determined according to the pressure gradient formula (1) and the volume flow rate gradient formula (2) caused by the movement of the working medium in the structure to be minimum:

p is the pressure of the working medium, w is the frequency of oscillation of the working medium in the pipeline, l is the inductance per unit length, r_μImpedance per unit length, U the volume flow rate of the working medium flow, c the capacitance per unit length, r_kAnd g is a volume flow source term, i is an imaginary number unit, and the capacitance, the inductance and the impedance corresponding to the mutation structure can be obtained by minimizing the pressure gradient and the volume flow rate gradient generated when the working medium flows through the mutation structure, so that the structural parameters of the mutation structure are reasonably distributed.

The core cavity of the low-temperature control box is connected with the room-temperature end stable pressure air source through the low-temperature pipeline, and the low-temperature pipeline is provided with the pressure fluctuation module in the suppression system, so that pressure oscillation induced by temperature gradient on the low-temperature pipeline can be suppressed, on one hand, unfavorable pressure fluctuation in the low-temperature pipeline system can be suppressed, and the problems of large heat leakage loss of the system, unstable pressure measurement and the like caused by thermoacoustic oscillation are solved, on the other hand, the low-temperature control box is easy to realize and has reliable performance.

Furthermore, based on the thermoacoustic oscillation theory and the resistance-capacitance regulation thought, the invention searches for a proper structural parameter configuration by adopting an integration mode that a dynamic-dissipative impeller is connected in series with a sudden change structure with inconsistent bidirectional resistance-capacitance based on the design concept that a pressure fluctuation suppression structure is matched with a pressure gradient and a volume flow rate gradient generated when a working medium flows through the structure, so that the pressure gradient and the volume flow rate gradient corresponding to the acoustic inductance, the acoustic capacitance and the impedance are minimized, and the oscillation is suppressed.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

Fig. 2 is a schematic structural view of the impeller 7 of the present invention.

Fig. 3(a) is a schematic structural view of a multi-layer density uneven fin of the pressure fluctuation suppression module according to the present invention.

FIG. 3(b) is a top view of a multi-layer uneven density fin of the pressure fluctuation suppression module according to the present invention.

Fig. 4 is a schematic structural diagram of a gradually expanding or gradually contracting regulating element of the pressure fluctuation suppression module according to the present invention.

In the figure: 1-a low-temperature control box, 2-a refrigerator, 3-a core cavity, 4-a low-temperature pipeline, 5-a stable pressure air source, 6-a pressure fluctuation suppression module, 7-an impeller, 8-a mutation structure, 6.1-a multilayer density uneven fin structure, 6.2-a gradually expanding or gradually contracting type regulating and controlling element and 9-fins.

Detailed Description

The present invention will be described in further detail with reference to the following drawings and examples, but the present invention is not limited thereto.