Comparison of FEM calculated heat transfer coefficient in a minichannel using two approaches: Trefftz base functions and ADINA softwareBeata Maciejewska, Paweł Łabędzki, Artur Piasecki and Magdalena PiaseckaEPJ Web Conf., 143 (2017) 02070DOI: https://doi.org/10.1051/epjconf/201714302070