CN-121994522-A - Wide-working-condition high-stability two-phase experiment circulating system and testing method thereof

CN121994522ACN 121994522 ACN121994522 ACN 121994522ACN-121994522-A

Abstract

The invention discloses a wide-working-condition and high-stability two-phase experimental circulation system and a testing method thereof, and relates to the field of electronic device thermal management. The experimental system realizes a wide-working-condition and high-stability two-phase flow circulation testing environment by cooperating the pumping unit and the flow control and pressure stabilization unit, can actually test the flow heat exchange performance of the two-phase flow heat exchanger under different inlet flow rates, supercooling degrees and dryness, monitors multidimensional data such as the temperature, the pressure, the flow state and the like of each key node in the loop in real time, so as to completely reflect the comprehensive performance of the heat exchanger, and provides experimental basis and design reference for the operation of the electronic device two-phase flow cooling system and the optimal design of the heat exchanger.

Inventors

DU SHEN
SHI DA
HUANG YANPEI
HUANG JINYIN
MIAO JIANYIN
HE YALING

Assignees

西安交通大学
北京空间飞行器总体设计部

Dates

Publication Date: 20260508
Application Date: 20260326

Claims (10)

1. The two-phase experimental circulation system with wide working conditions and high stability comprises an experimental section (14) arranged in a refrigerant circulation loop, and a test sample piece arranged in the experimental section (14), and is characterized by further comprising a pumping unit, a pressure control unit, a temperature control unit, a condensing unit and a data acquisition unit, wherein the test sample piece is a two-phase flow heat exchanger; the pumping unit is used for maintaining closed circulation of the refrigerant in the loop; The pressure control unit comprises a liquid storage tank (15), the bottom of the liquid storage tank (15) is connected in parallel in a loop behind the experimental section (14) through a stop valve (12) and is used for storing redundant refrigerant in the system, and the pressure of the refrigerant in the loop is regulated and controlled by regulating and controlling the temperature of the refrigerant in the tank; the temperature control unit is used for controlling the supercooling degree and dryness of the inlet refrigerant of the experimental section (14); the condensing unit is used for condensing the two-phase refrigerant at the outlet of the experimental section (14); The data acquisition unit is used for monitoring and obtaining thermodynamic parameters of key positions in the experimental system in real time.
2. The wide-working-condition high-stability two-phase experiment circulating system according to claim 1, wherein the experiment section (14) comprises two flexible metal corrugated hoses for installing test samples, the inlet and the outlet of each test sample are connected to one metal corrugated hose on the corresponding side through threads respectively to form a detachable fluid passage, the experiment section (14) can adapt to test samples with different dimensions by adjusting the bending form and the extending length of the metal corrugated hose, flexible adjustment of the installation position and the passage length is realized, the front and the rear of the experiment section (14) are respectively provided with a self-sealing interface (13) and an auxiliary stop valve (24) so as to be convenient for disassembly and assembly, and the two-phase flow heat exchanger is a parallel microchannel heat exchanger, a manifold microchannel heat exchanger or a jet flow heat exchanger.
3. The wide-working-condition high-stability two-phase experimental circulation system according to claim 1, wherein the pumping unit consists of a servo motor (1), a gear pump (2) and a filter (21), wherein the servo motor (1) drives the gear pump (2) to drive a refrigerant to overcome the flow resistance of a system loop and maintain circulation, and the filter (21) is positioned in front of an inlet of the gear pump (2) and is used for filtering solid impurities possibly carried by the refrigerant in the loop and protecting the gear pump (2); The pressure control unit further comprises an exhaust valve (17) and a second constant temperature water tank (18), wherein the exhaust valve (17) is positioned at the top of the liquid storage tank (15) and is used for decompressing and discharging non-condensable gas mixed in the loop, the second constant temperature water tank (18) is connected to a spiral heat exchange pipe inside the liquid storage tank (15), constant temperature circulating water is sent into the tank to exchange heat with the refrigerant in the tank, and the two-phase refrigerant in the liquid storage tank (15) is heated or cooled so as to increase or decrease the pressure of the two-phase refrigerant in the tank, so that the pressure of the refrigerant in the loop is regulated and controlled.
4. The wide-working-condition and high-stability two-phase experimental circulation system according to claim 1, wherein the temperature control unit consists of a plate heat exchanger (7), a first constant-temperature water tank (8), an electric heater (9) and a power regulator (10); one side of the plate heat exchanger (7) is connected with a loop, the other side of the plate heat exchanger is connected with a first constant temperature water tank (8), and the supercooling degree of the inlet refrigerant of the experimental section (14) is controlled by adjusting the temperature of circulating water in the first constant temperature water tank (8) to heat or cool the refrigerant; The electric heater (9) is positioned between the plate heat exchanger (7) and the inlet of the experimental section (14), is a tube type heating tube array inserted into a refrigerant pipeline, converts electric energy into heat energy by using a Joule effect to heat the refrigerant, and precisely controls specific voltage and current by the power regulator (10) so as to realize constant-power heating and further control the dryness of the refrigerant at the inlet of the experimental section (14).
5. The wide-working-condition high-stability two-phase experimental circulation system according to claim 1, wherein the condensing unit consists of a condenser (19) and a water chilling unit (20); the condenser (19) is a shell-and-tube heat exchanger, the tube side is connected with a water chilling unit (20), the shell side is connected with a refrigerant loop, and low-temperature cold water and two-phase refrigerant at the outlet of the experimental section (14) are subjected to non-contact heat exchange through the wall of the heat exchange tube, so that the refrigerant is condensed.
6. The wide-working-condition and high-stability two-phase experimental circulation system according to claim 1, wherein the data acquisition unit consists of a mass flowmeter (5) in a loop, temperature sensors (22) at key positions, a pressure sensor (23) and a liquid viewing mirror (11) and is used for monitoring the flowing heat exchange state of a refrigerant in the circulation system in real time and providing data support and regulation basis for the pumping, flow control, pressure stabilization, pressure control, temperature control and condensation units.
7. The wide-working-condition and high-stability two-phase experimental circulation system according to claim 1 is characterized in that the wide working condition refers to a flow range of 0.01-0.30 kg.s -1 and a pressure range of 0.1-2.0 MPa in a system test working condition, and the high stability refers to a thermodynamic parameter change range of less than 10% in a system test process.
8. The wide-operating-range and high-stability two-phase experimental circulation system according to any one of claims 1 to 7, further comprising a flow control and voltage stabilization unit; The flow control and pressure stabilizing unit consists of an electronic regulating valve (3), a pulsation damper (4) and a dynamic regulating valve (6); The electronic regulating valve (3) is connected to the front and the rear of the pumping unit in a bypass way, and is used for controlling the flow of the refrigerant actually flowing through the experimental section (14) in a matching way before the part of the refrigerant at the outlet of the pumping unit is returned to the pumping unit in a bypass way; The pulsation damper (4) is positioned behind the pumping unit and is used for eliminating the pressure pulsation and the flow pulsation of the refrigerant caused by the operation of the pump, so as to play a role in stabilizing the pressure and the flow of the fluid; The dynamic regulating valve (6) is positioned between the pulsation damper (4) and the experimental section (14), automatically regulates the opening of the valve according to the front-rear pressure difference change of the valve so as to stabilize the flow, balances the influence of the extra compressible volume brought by the pulsation damper (4) on the integral pressure drop-flow characteristic curve of the loop, and improves the circulation stability of the two-phase flow.
9. The method for testing the wide-working-condition and high-stability two-phase experimental circulation system according to claim 1, which is characterized by comprising the following steps: step 1, installing a test sample in an experiment section (14), vacuumizing a loop, and then filling a refrigerant until the liquid level in a liquid storage tank (15) reaches 1/2, and stopping; step 2, adjusting the temperature of the refrigerant in the liquid storage tank (15) to the saturation temperature corresponding to the saturation pressure, and adjusting the pressure of the refrigerant in the circulation loop to the expected saturation pressure through the pressure transmission between the refrigerant in the tank and the refrigerant in the loop; Step 3, adjusting the temperature of cold water in the condenser (19) to be lower than the saturation temperature of the refrigerant, ensuring that the refrigerant before the pumping unit is supercooled liquid, starting the pumping unit to pump, and controlling the opening to enable the inlet flow of the experimental section (14) to reach a set value Step 4, controlling the supercooling degree and dryness of the inlet refrigerant of the experimental section (14) through a temperature control unit; And 5, enabling the parameters of the refrigerant before the experimental section (14) to meet the test conditions and keep stable, starting the external loads of the simulated heat source and the simulated vibration source which are arranged on the surface of the test sample piece in the experimental section (14), and collecting the flowing heat exchange state parameters of the refrigerant at a plurality of positions in the system in real time through the data collecting unit.
10. The test method according to claim 9, wherein the temperature control unit consists of a plate heat exchanger (7), a first constant temperature water tank (8), an electric heater (9) and a power regulator (10), wherein one side of the plate heat exchanger (7) is connected with a loop, the other side of the plate heat exchanger is connected with the first constant temperature water tank (8), and the electric heater (9) is positioned between the plate heat exchanger (7) and an inlet of an experimental section (14) and is a cylinder type heating pipe array inserted into a refrigerant pipeline; The method comprises the steps of step 4, for supercooling working conditions, adjusting the water temperature of a first constant-temperature water tank (8) without starting an electric heater (9) to enable the refrigerant in front of an experiment section (14) to reach a set supercooling degree, for superheating working conditions, adjusting the water temperature of the first water tank (8) to enable the refrigerant in front of the electric heater (9) to reach a saturated state, estimating electric heating power required for achieving the set dryness through conservation of heat, enabling the electric heater (9) to heat with constant power according to the required power through a power regulator (10), and enabling the refrigerant in front of the experiment section (14) to reach the set dryness.

Description

Wide-working-condition high-stability two-phase experiment circulating system and testing method thereof Technical Field The invention belongs to the technical field of electronic device heat management, and particularly relates to a wide-working-condition and high-stability two-phase experiment circulating system and a testing method thereof. Background The two-phase flow cooling technology is based on the high latent heat phase change heat exchange process of the refrigerant, has the advantages of high heat exchange coefficient, good temperature uniformity, low pumping power requirement and the like, and has become one of research hot spots in the field of heat management of high heat flux electronic equipment. However, due to the complex phase state characteristics of the gas-liquid two-phase flow, the flow pattern evolution, the flow characteristics and the heat transfer performance of the refrigerant in the heat exchanger can show obvious nonlinear characteristics along with the changes of saturated pressure, mass flow, load thermal power and the like, and once the critical heat flow density state is reached, the potential safety hazards such as local overheating failure of electronic devices are easily caused. Therefore, the mapping relation between different working condition parameters and the flowing heat transfer characteristics of the heat exchanger is clarified through experiments, and the method has important guiding significance for promoting engineering application of the technology in the field of electronic heat management. The flow condition of the existing two-phase flow cooling technology experimental device is completely determined by a circulating pump, so that a flow regulation mechanism of the experimental device has double technical bottlenecks, namely, firstly, the experimental device is limited by the working principle of a positive displacement pump body, periodic pressure/flow pulsation phenomenon is inevitably generated in a loop, so that dynamic evolution characteristics between pressure and flow of a two-phase heat exchanger cannot be captured, secondly, the inherent mechanical characteristics of a pump body enable the experimental device to be difficult to realize accurate regulation and control of a wide-area flow condition, and particularly, a stable flow state is difficult to maintain under a small-flow condition required by a micro-channel heat exchanger, and the limitations of a flow control system have severely restricted the reliability and the working condition applicability of experimental data. Disclosure of Invention In order to overcome the defects of the prior art, the invention aims to provide a wide-working-condition and high-stability two-phase experimental circulation system and a testing method thereof, which can be used for testing the actual flow heat exchange performance of a two-phase flow heat exchanger in a high-stability manner under a wide flow and pressure working condition range by using the experimental device, thereby providing theoretical basis and experimental support for the design and performance optimization of the heat exchanger used in the two-phase flow cooling technology of an electronic device. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: The two-phase experimental circulation system with wide working conditions and high stability comprises an experimental section arranged in a refrigerant circulation loop, a test sample piece arranged in the experimental section, a pumping unit, a pressure control unit, a temperature control unit, a condensing unit and a data acquisition unit, wherein the test sample piece is a two-phase flow heat exchanger; the pumping unit is used for maintaining closed circulation of the refrigerant in the loop; The pressure control unit comprises a liquid storage tank, the bottom of the liquid storage tank is connected in parallel in a loop behind the experimental section through a stop valve and is used for storing redundant refrigerant in the system, and the pressure of the refrigerant in the loop is regulated and controlled by regulating and controlling the temperature of the refrigerant in the tank; the temperature control unit is used for controlling the supercooling degree and dryness of the inlet refrigerant of the experimental section; the condensing unit is used for condensing the refrigerant exiting the experimental section; the data acquisition unit is used for monitoring and obtaining thermodynamic parameters such as temperature, pressure, flow and the like of key positions in the experimental system in real time. In one embodiment, the experimental section is a position for installing a test sample, and comprises two bendable and adjustable metal corrugated hoses for installing the test sample, wherein the test sample can be flexibly adjusted according to the size of the test sample, a self-sealing interface and an auxiliary stop valve are arrange