DEVELOPMENT OF A FLOW DISTRIBUTION AND DESIGN-MODEL FOR TRANSPIRED SOLAR COLLECTORS

Unglazed, transpired solar collectors offer a low-cost, high-efficienc y means for preheating outside air for ventilation and crop drying app lications. Although large building wall applications for these collect ors have generally performed well in the field, many have exhibited po or flow distribution which can prevent maximum efficiency from being a chieved. The objective of this work was to develop a computer model wh ich would run quickly on a personal computer and allow designers of tr anspired collectors to easily adjust geometric parameters to achieve r easonable flow uniformities and to determine efficiencies. This paper describes how this model was developed and includes results from model runs. In order to allow the model to run quickly on the PC, pipe netw ork methods were used to develop a set of simultaneous equations in th e unknown flow rates. Previous research results on heat exchange effec tiveness, pressure drop, and wind heat loss were incorporated. (C) 199 7 Elsevier Science Ltd.