Heat Transfer and Two-Phase Flow Regimes in Manifolded Microgaps: Performance Comparison Between R245fa and FC-72

Two-phase embedded cooling has great potential for meeting the increasing thermal management needs of high-heat flux electronics. The use of manifold-microchannels further enhances the effectiveness of embedded cooling while maintaining low pressure drop and pumping power. Previous research has shown that thermodynamic quality drives the thermo-fluid phenomena in the channel, including the prevailing flow regime, the transition to dryout, and the local heat transfer coefficients. The flow phenomena are also strongly dependent on the properties of the working fluid. The current study investigates the performance of FC-72 and R245fa in an enlarged visualization manifold-microchannel, referred to as a "microgap" channel.