| The study of the heat transfer in greenhouse, heat storage layer and passive solar heating room has an important effect on decreasing the energy consumption in building. In this paper, the analysis of the convection heat transfer in greenhouse, the heat storage layer of rock bed, the passive solar heating with greenhouse, the thermal convection diode and the passive solar composite wall with porous absorber has been conducted. In a lean-to passive solar greenhouse, a mathematical model based on energy conversation and a one-dimensional mathematical model for the unsaturated porous medium have been founded and developed to predict the temperature and moisture content in soil and the enclosed air temperature in the greenhouse. The effect between the soil temperature and that of the air in the greenhouse exists and there is thermal inertia in soil bed. Solar irradiation absorber, heat storage and insulation are the main effects of the north massive wall on greenhouse, which is influenced by the structure and the material. So, the build-up north wall with thermal insulation layer may be chosen .The specific heat capacity and thermal conductivity of wall material have a remarkable effect on the north wall temperature distribution. The calculated values of the soil and air temperature in the greenhouse correspond with the observed data in experiment. Thus, the conclusions drawn from the calculation are correct. The low-turbulent model has been employed to study the effects of the cover material of the north inside wall and the glass roof inclined angle on the temperature distribution and gas flow in greenhouse. The greenhouse location, solar radiation transmission into the greenhouse, the temperature distribution and gas flow in greenhouse and the space utility should all be taken into account for building a greenhouse. The cover material of the inside surface of the north wall, which is black paint or white paint, could be selected to increase the absorption or reflection of solar irradiation to meet the requirement of the temperature or the light irradiation in greenhouse. Heat transfer and air flow in a rock bed, which is used as solar absorber and storage layer, are also studied. If porosity is kept within certain range, increasing the rock size causes an increase of the capability of thermal storage and heating effects; Increasing the porosity of thermal storage materials results in an increase of the bed temperature but a decrease of the rock mass. In passive solar heating room with greenhouse and heat storage, thermal insulation of solar heating room has significant effects on temperature distribution and airflow in the heating chamber of this solar system. Solar irradiation absorber, heat storage and insulation are the main effect factors of the passive solar heating room Heat transfer and gas flow in rock bed worked as solar absorber and storage layer have also been studied, including transport properties.Heat transfer and liquid flow in a heating wall with thermal diodes – passive solar heating device which absorb and accumulate solar energy and then transport heat preferentially to the inside of a building, has been investigated. The system contains thermal diode to prevent reverse circulation at night time. A mathematical model based on energy equilibrium was founded and may be used to predict the variation of the isotherms and streamlines within the convective thermal diode versus time of a day. It has been found that the thermal diodes leads to energy savings higher compared with the reference cells without it and reduce the thermal losses at night-time. In the composite solar wall with porous absorber, which has been first designed, the unsteady numerical simulation is employed to analyze the performance of the flow and temperature field versus the change of the solar radiant and temperature outside in a day, the porous absorber works as thermal insulator in a degree when no solar shining is available. The influence of the particle size and the porosity within the porous absor...
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