The top heat-loss factor (U-t) of a box-type solar cooker varies with
plate temperature, wind heat-transfer coefficient and ambient temperat
ure. A method for correlating U-t with these variables is presented fo
r a cooker with double glazing. A set of equations is developed for co
rrelating data obtained in indoor experiments at different plate tempe
ratures and wind speeds. (C) 1997 Elsevier Science Ltd.