The Research On The Numerical Simulation Of Humidity Distribution In Solar Greenhouse

The solar greenhouse is closed in order to keep warm in winter and spring, then it lead to the moisture can not escaped from indoor and the air humidity is high. The high humidity environment is not only harmful to plant growth and production, it is easy to cause physiological disorder of crops, also limits the transpiration of plants, effects the root system on soil nutrient absorption and utilization, and increasing plant disease occurrence, so it is important to control the humidity of greenhouse. To get the distribution of humidity in a certain period of time in the greenhouse on the condition of border irrigation in winter, using the computational fluid dynamics (CFD) method to simulate the environment of the greenhouse, and comparing the results of CFD simulation and experimental test results in my study. Then we can take reasonable measures to artificial regulation, improve crop growth conditions and prevent disease through the humidity changes.Based on the experimental results, the three-dimensional CFD model of the greenhouse under natural ventilation condition was established by CFD method. In the model, using standard k- ? turbulence model and standard wall function method to encrypt the near wall region. DO radiation model is used to dispose solar radiation. The humidity is described using a component transport model. The finite volume method is used to solve the differential equation of the flow field.By comparison of the simulation results and experimental results under the condition of non plant, the average error of indoor air temperature between simulated and measured values is 2.5%, the average error of indoor air humidity between simulated and measured values is 3.3%. The simulation results and the experimental results show that the fitting degree is higher, and it is proved that the CFD model can reflect the internal situation of the greenhouse. From this, we can guide the production and operation of the actual greenhouse by the experiment and optimization of the CFD model.