Solar-Powered Water Pump and Related Problem of Boiling on Downward-Facing Surface

Conceptual design of a new type solar-powered water pump (SPWP) integrated into flat plate solar collector (FPC) has been carried out. SPWP represents simple heat engine-membrane pump operating through alternating of processes of evaporation and condensation in its working chamber. It should provide circulation of water using part of absorbed by FPC heat and returning it finally to the same heat carrier Two basic versions of structural layout of FPC have been considered: the first - with flow-through absorber (with circulation of water through riser pipes welded to absorbing plate) and the second with absorber with gravity-assisted heat pipes (GAHPs). In terms of efficient operation important role of proper organization of boiling heat transfer on downward-facing heating surface of working chamber has been revealed. Thermo-hydrodynamic peculiarities of this process are considered. The results of preliminary experimental study of boiling heat transfer on downward-facing heating surface are presented.