1. Thermal and Electrical Systems Research Laboratory (THELES), Cluster of Engineering Technology, Mechanical Engineering Department, KU Leuven, Sint-Katelijne-Waver 2860, Belgium e-mail:
2. Fellow ASME Thermal and Electrical Systems Research Laboratory (THELES), Cluster of Engineering Technology, Mechanical Engineering Department, KU Leuven, Sint-Katelijne-Waver 2860, Belgium e-mail:
3. GeoTherma, Ambachtenstraat 14A, Lubbeek 3210, Belgium e-mail: