STUDIES ON METHODS OF REDUCING HEAT LOSSES FROM FLAT PLATE SOLAR COLLECTORS Progress Report, August 1, 1974-January 31, 1976

摘要

Improvements to flat plate solar collectors for heating and cool-ing of buildings have been evaluated through three parallel studies. The first study has demonstrated suppression of free convection by a honeycomb at all angles of inclination. Reductions by a factor of 5 in the free convective heat loss are reported, and equations and charts permitting the rational design of honeycombs for convection suppression in solar collectors are presented. The second study has resulted in a precise, easily programmable set of equations for the free convective heat loss through the air gaps in flat plate solar collectors, for any angle of tilt. The third study has theoretically and experimentally de¬monstrated that the solar transmittance of a flat transparent cover for a solar collector can be very substantially increased by V-corrugating. Since V-corrugating should also decrease the free convective and radi¬ant losses, substantial improvements in collector efficiency are pre¬dicted.