Evaporative heat transfer analysis of a micro loop heat pipe with rectangular grooves

• The performance of a micro loop heat pipe is modeled using the principles of thin film evaporation.
• The model utilizes an in-situ calculation of the evaporative heat transfer coefficient in capillary grooves.
• The model incorporates a micro flow solver to estimate the length of the wetted evaporating region.
• The integrated model predicts the thermal and flow characteristics of a micro loop heat pipe with rectangular grooves.

This study focuses on the thermal and capillary analysis of a micro loop heat pipe for the thermal management of electronic devices and systems. A model is developed using the principles of thin film evaporation to predict the evaporative heat transfer coefficient in grooved capillary structures. In addition, a micro-flow submodel is developed to compute the dry-out distance in rectangular capillary grooves. These submodels are incorporated into our previously developed system-level loop solver model to simulate the performance of a flat micro loop heat pipe. The integrated model predicts the thermal performance, evaporator surface temperature, and local and average heat transfer coefficients as a function of the applied heat load. The modeling results are verified by comparison with the experimental data for a similar device and a good agreement is obtained.