Numerical investigations of phase change material (PCM) based thermal control module (TCM) under the influence of low gravity environment

Abstract Transport processes associated with melting of an electrically conducting Phase Change Material (PCM), placed inside a rectangular enclosure, under low-gravity environment, and in the presence of a magnetic field is simulated numerically. Electromagnetic forces damp the natural convection as well as the flow induced by sedimentation and/or floatation, and thereby simulating the low gravity environment of outer space. Computational experiments are conducted for both side-wall heating and top-wall heating under horizontal magnetic field. The governing equations are discretized using a control-volume-based finite difference scheme. Numerical solutions are obtained for true low-gravity environment as well as for the simulated-low-gravity conditions resulted by the presence of a horizontal magnetic field. The effects of magnetic field on the natural convection, solid phase floatation/sedimentation, liquid-solid interface location, solid melting rate, and flow patterns are investigated. It is found that the melting under low-gravity environment can reasonably be simulated on earth via applying a strong horizontal magnetic field. However, the flow patterns obtained for the true low-gravity cases are not similar to the corresponding cases solved for the simulated-low-gravity environment.

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The effect of water’s presence around the Phase Change Material

Thermal Science ◽

10.2298/tsci180922301s ◽

2020 ◽

Vol 24 (6 Part B) ◽

pp. 4049-4059 ◽

Cited By ~ 2

Author(s):

Haythem Shili ◽

Kamel Fahem ◽

Souad Harmand ◽

Jabrallah Ben

Keyword(s):

Phase Change ◽

Phase Change Material ◽

Thermal Protection ◽

Flow Direction ◽

Operating Time ◽

Thermal Control ◽

Melting Time ◽

Standard Case ◽

Time Flow ◽

Change Material

As part of the research in the field of thermal control of electronic components, a phase change material is confined in a liquid and is heated vertically on one side by a hot plate. The presence of the liquid around the phase change material prevents the formation of air bubbles produced in case of direct contact between the hotplate and the phase change material (extends the lifetime of the phase change material by reducing overheating zones). It improves heat transfer by increasing the thermal conductivity around the phase change material (raising the thermal exchange surface) and by accelerating the convective transfer. This work examines experimentally and numerically the effect of the water on the phase change material and on the heating plate. The water is used around the phase change material and a comparative study of the comportment of some important parameters like the melt front form, melting time, flow direction, temperature, and operating time is realized. It is found that the presences of the liquid around the phase change material seems to be more interesting for a thermal protection role than the standard case of the phase change material directly heated by the hotplate.

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A hollow microlattice based ultralight active thermal control device and its fabrication techniques and thermal performances

Journal of Micromechanics and Microengineering ◽

10.1088/1361-6439/ac3be2 ◽

2021 ◽

Author(s):

Wenjun Xu ◽

Longquan Liu ◽

Junming Chen ◽

Xinying Lv ◽

Yongtao Yao

Keyword(s):

Phase Change ◽

Phase Change Material ◽

Forced Convection ◽

Liquid State ◽

High Efficiency ◽

Thermal Control ◽

Test System ◽

Control Device ◽

Active Cooling ◽

Change Material

Abstract This paper introduces a new thermal control device which has not only low weight and high efficiency but also passive and active cooling capabilities. The thermal control device mainly consists of hollow graphene-enhanced-metallic microlattice material, phase change material (PCM) and a peristatic pump. The PCM is inside the spatial-interconnected millimeter-scale diameter tubes, which are the basic constitution of the hollow microlattice material, in addition, the peristatic pump was connected with the tubes and used to force the liquid-state PCM to circulate inside the interconnected thin tubes. Thus, the proposed thermal control device takes combined advantages of the ultralight and high thermal transfer properties of the hollow graphene-enhanced-metallic microlattice materials, the thermal storage capability of the PCM and forced convection of the PCM driven by the peristatic pump as the PCM is in liquid state. The manufacturing process of the active thermal control device was also developed and proposed, which mainly includes additive manufacturing, composite electroless plating, polymer etching, liquid phase change material injecting and the peristatic pump connecting. In addition to that, a thermal test system was built and the effective thermal conductivities of the thermal control device in passive cooling and with active cooling modes were experimentally studied. The thermal control device can absorb heat and actively dissipate heat by means of forced convection. Consequently, the proposed active thermal control device can be used to guarantee the electronic components and spacecrafts operate in a specific temperature range.

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