The effectiveness of using greenhouse soil for heat storage: A comsol multiphysics™ model

One of the problems currently facing the agriculture sector in egypt is the scarcity of energy sources needed to maintain the temperature inside greenhouses to enable farmers to grow out of season crops. to contribute to the solution of this problem,it is suggested to use the greenhouse soil as an energy storage medium,where warm liquid passes during the daytime to heat the soil and then the heat is recovered by a cold liquid at night. this paper presents a mathematical model that tests the heat storage efficiency of a greenhouse ground,for two typical egyptian soil types,where one is clay based and the other is sand based. the model is simulated using comsol multiphysics 4.3b and compares the effectiveness of heat transfer when using three different pipe materials,copper,hdpe and pvc,over a 10 hours period. the results obtained indicate that the sandy soil is egypt exhibits a higher heat absorption capacity than the clay soil. also,from the three pipe materials simulated,copper is by far the most effective,followed by hdpe then pvc,both of which show comparable heat propagation trends.