CN-121548023-B - Plate type pulsating heat pipe electric element radiator with cooperative enhanced heat transfer

CN121548023BCN 121548023 BCN121548023 BCN 121548023BCN-121548023-B

Abstract

The invention belongs to the technical field of electric element heat dissipation, and particularly relates to a plate type pulsating heat pipe electric element radiator with cooperative enhanced heat transfer. The invention is to braze a porous copper wire mesh capillary core structure on the inner wall surface of an evaporation section to provide strong capillary force, and simultaneously interconnect the large multi-loop elbows of a condensation section through tapered connecting grooves and micro-groove channels to form a global pressure and working medium blended composite condensation flow channel network. Compared with the traditional pulsating heat pipe, the invention can effectively solve the problems of flow stagnation or pressure imbalance caused by uneven local heating or increased flow resistance through the capillary strengthening of the evaporation section and the multi-loop cooperation of the condensation section, and effectively improve the running stability and reliability of the system under uneven heat load.

Inventors

LIU JIANHONG
Ma Shunfang
SHANG FUMIN
XU HAORAN
LI WENJIE
ZHAO YANG
YANG KAI
ZHENG CHAOFAN

Assignees

长春工程学院

Dates

Publication Date: 20260512
Application Date: 20260119

Claims (5)

1. A plate type pulsating heat pipe electric element radiator with a composite evaporation layer and a micro-groove condensation channel for cooperatively enhancing heat transfer comprises a plate type pulsating heat pipe substrate (8) and a condensation section (1), an adiabatic section (2) and an evaporation section (3) which are arranged on the plate type pulsating heat pipe substrate (8), and is characterized in that the condensation section (1) adopts a composite condensation flow channel network (10) formed by a main groove channel (7), a micro-groove channel (4) and a tapered connecting groove (9) for connecting the main groove channel (7), the micro-groove channel (4) and the micro-groove condensation channel, the condensation section (1) is a multi-elbow closed loop formed by the main groove channel (7), the micro-groove channel (4) and the tapered connecting groove (9), a capillary core structure (5) formed by multi-layer copper wire mesh brazing is arranged in the evaporation section (3), the capillary core structure (5) is fixed at the bottom of the evaporation section (3) through vacuum brazing, and when the micro-groove channel (4) is designed, the micro-groove channel (4) is used for realizing pressure relief of adjacent elbows without affecting working medium oscillation in a pipe, and the following requirements are met: ; ; ; ; In the formula, P cap -capillary pressure, pa; Sigma-surface tension, N/m; Theta-wetting contact angle, cos theta is 1.0; -microgroove height, m; P h -hydrostatic pressure, pa; -liquid phase density, kg/m3; g-gravitational acceleration, m/s 2 ; z-the liquid level difference at two sides, m; p d -dynamic pressure of liquid plug, pa; acceleration of the liquid plug/column, m/s2; L eff -equivalent liquid column length affected by acceleration, m.
2. The plate type pulsating heat pipe electric element radiator with the synergistic enhancement of heat transfer by the composite evaporation layer and the micro-groove condensing channels as claimed in claim 1, wherein the width of the main groove channel (7) is 2.0 mm, the depth is 2.0 mm, the width of the micro-groove channel (4) is 0.3 mm, and the depth is 0.2 mm.
3. The plate type pulsating heat pipe electric element radiator with the synergistic enhancement of heat transfer by the composite evaporation layer and the micro-groove condensation channel as claimed in claim 1, wherein the capillary core structure (5) is a 100-150 mesh woven copper wire mesh, the wire diameter is 0.08-0.10 mm, and the single-layer thickness is 0.1 mm.
4. A plate type pulsating heat pipe electric element radiator with cooperative enhanced heat transfer of a composite evaporation layer and a micro-groove condensing channel as claimed in claim 2 is characterized in that the main groove channel (7) and the micro-groove channel (4) form a composite condensing flow channel network (10) capable of achieving self-adjusting partial pressure effect through a tapered connecting groove (9) along a runner at the lower part of an elbow.
5. The plate type pulsating heat pipe electric element radiator with the synergistic enhancement of heat transfer of the composite evaporation layer and the micro-groove condensation channel as claimed in claim 1 is characterized in that the upper part of the plate type pulsating heat pipe substrate (8) is sealed by a polycarbonate or acrylic transparent plate, so that visual test and optical observation are realized.

Description

Plate type pulsating heat pipe electric element radiator with cooperative enhanced heat transfer Technical Field The invention belongs to the technical field of electric element heat dissipation, and particularly relates to a plate type pulsating heat pipe electric element radiator with cooperative enhanced heat transfer. Background The current electric element is developing towards high power, high integration and micro scale, so the heat dissipation problem is more and more prominent, the pulsating heat pipe is a novel heat pipe which appears in nineties of the last century, and the pulsating heat pipe has the advantages of good temperature uniformity, high heat dissipation efficiency and the like, thus providing an effective heat dissipation technology for a plurality of high-power electric elements. However, the conventional pulsating heat pipe has multiple technical challenges in engineering application, and the disadvantages are mainly that firstly, the starting and running of the system are highly dependent on external working conditions, working medium oscillation flow in the pulsating heat pipe is driven by enough initial temperature difference and is influenced by installation angles, when the working medium distribution is unbalanced in a horizontal or inverted installation state, continuous air lock or liquid plug phenomenon is easily caused, the starting failure of the system or the time for reaching a stable working state is obviously prolonged, secondly, because the internal flow is in random oscillation characteristic, bubble splitting and generating are uncontrollable, the system is often accompanied with large temperature fluctuation in the running process, the whole temperature uniformity is reduced, and moreover, the flat micro-groove with a plate structure is often insufficient in capillary reflux driving force, and as the heat flow density is increased, when the working medium supplementing rate in an evaporation section can not meet the evaporation requirement, the phenomenon of local drying is extremely easy to be caused, the phase change interruption not only limits the maximum heat transfer capacity, but also can cause irreversible performance attenuation, and finally, the conventional manufacturing process mainly adopts a simple grooving or mechanical processing channel, and is difficult to form a capillary structure with controllable aperture and wettability, so that the distribution capacity is insufficient. Disclosure of Invention In order to solve the problems of insufficient boiling heat transfer, uneven flow of a condensing section, high overall heat resistance and the like of an evaporation section in the existing pulsating heat pipe, the invention provides a plate type pulsating heat pipe electric element radiator with a composite evaporation layer and a micro-groove condensing channel for cooperatively enhancing heat transfer. The invention relates to a plate type pulsating heat pipe electric element radiator with a composite evaporation layer and a micro-groove condensation channel for cooperatively enhancing heat transfer, which is characterized in that a porous copper wire mesh is brazed on the inner wall surface of an evaporation section on the basis of a traditional pulsating heat pipe to provide strong capillary force, and simultaneously large elbows of a plurality of loops of the condensation section are interconnected through tapered connecting grooves and the micro-groove channels to form a global pressure and working medium blended composite condensation flow channel network; and be provided with the fixed copper wire mesh capillary core structure of brazing in the evaporation zone, this structure is integrated through the fixed copper wire mesh capillary layer of vacuum brazing at evaporation zone inner wall for construct capillary reflux channel and strengthen the phase transition boiling process, can form higher capillary pressure and good wettability in the evaporation zone, can realize stable liquid backward flow, thereby avoid local dry up and promote the reliability of pulsation heat pipe under high heat flux density. The condensation section is a composite condensation flow channel network formed by the mutual communication of the main channel and the micro channel through the tapered connecting grooves, the structure can obviously reduce the flow resistance and promote the condensation heat exchange uniformity, can effectively relieve the stagnation of air plugs and liquid plugs which are easy to occur in the traditional pulsating heat pipe, improves the oscillation frequency in the pulsating heat pipe and the controllability of the heat transfer process, and ensures that the integral temperature fluctuation is smaller and the thermal resistance is lower. Further, a 100-150 mesh woven copper mesh is selected as a capillary core structure in the evaporation section, the wire diameter is 0.08-0.10 mm, the single-layer thickness is 0.1mm, and the capillary