Heat Transfer Characteristics and Boundary Conditions between North Wall of Chinese Solar Greenhouse and Environment

A one-dimensional unsteady-state heat transfer model for a three-layer north wall with a phase-change material used for thermal storage in a Chinese solar greenhouse was established． Implicit finite difference method was used to establish node temperature dispersion equation． Temperature distribution in the wall was calculated using Matlab programming． By analyzing thermal balance of the nodes on internal and external surfaces of north wall, rate of heat transfer between surfaces of north wall and environment was calculated and analyzed． Using Matlab fitting tool, functional relationship between heat transfer rate and wall surface temperature, outdoor air temperature, and solar radiation intensity was analyzed under various weather conditions． The results could provide reference material for optimizing and evaluating design of north wall of a solar greenhouse．