PCM thermal control unit for portable electronic devices: experimental and numerical studies

This paper investigates the effectiveness of a thermal control unit (TCU) for portable electronic devices by performing experimental and numerical analyses. The TCU objective is to improve thermal management of electronic devices when their operating time is limited to a few hours. It is composed of an organic phase change material (PCM) and a thermal conductivity enhancer (TCE). To overcome the relatively low thermal conductivity of the PCM, a TCE is incorporated into the PCM to boost its conductivity. The TCU structure is complex, and modeling an electronic device with it requires time and effort. Hence, this research develops approximate, yet effective, solutions for modeling the TCU, which employ effective thermo-physical properties. The TCU component properties are averaged and a single TCU material is considered. This approach is evaluated by comparing the numerical predictions with the experimental results. The numerical model is then used to study the effect of important parameters that are experimentally expensive to examine, such as the PCM latent heat, Stefan number, and heat source power. It is shown that the TCU can provide a reliable solution to portable electronic devices, which avoids overheating and thermally-induced fatigue, as well as a solution which satisfies the ergonomic requirement.

[1]  L. T. Yeh,et al.  Review of Heat Transfer Technologies in Electronic Equipment , 1995 .

[2]  R. C. Estes.  The effect of thermal capacitance and phase change on outside plant electronic enclosures , 1992 .

[3]  J. R. Ockendon,et al.  Modelling mushy regions , 1987 .

[4]  A. Abhat.  Low Temperature Latent Heat Thermal Energy Storage , 1982 .

[5]  Cristina H. Amon,et al.  Thermal Management Strategies for Embedded Electronic Components of Wearable Computers , 2000 .

[6]  Napoleon Leoni,et al.  Bayesian surrogates for integrating numerical, analytical and experimental data: application to inverse heat transfer in wearable computers , 1998, ITherm'98. Sixth Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (Cat. No.98CH36208).

[7]  Daniel P. Siewiorek,et al.  Thermal management and concurrent system design of a wearable multicomputer , 1997 .

[8]  Yogendra Joshi,et al.  Application of Phase Change Materials to Thermal Control of Electronic Modules: A Computational Study , 1997 .

[9]  Weiran Xu,et al.  Modeling Phase Change Material in Electronics using CFD - A Case Study , 2000 .

[10]  Fritz B. Prinz,et al.  THERMAL MODELLING AND EXPERIMENTAL TESTING OF MD* SPRAY SHAPE DEPOSITION PROCESSES , 1994 .

[11]  Cristina H. Amon,et al.  Transient thermal management of temperature fluctuations during time varying workloads on portable electronics , 1999 .

[12]  L. Chow,et al.  Thermal conductivity enhancement for phase change storage media , 1989 .