Research On The Simulation And Optimization Of The Environment Of Edible Mushroom Factory

The internal environment of mushroom house is one of the important factors that affect the growth of edible fungi. At present, though the monitoring technology on mushroom house internal environment and the measurement precision have been improving constantly, local measurement is still adopted to determine the internal environment distribution of the entire mushroom house. It is not able to reflect the distribution environment of the mushroom house fully. In recent years, computational fluid dynamics(CFD) technology has been widely applied in the research of greenhouse internal environment to save costs and improve the yield of greenhouse crops through the optimization of the greenhouse environment. Researching on the distributed internal environment of a mushroom house can obtain the further guidance of edible fungus production operation and the mushroom house design optimization. It is of great significance to improve the yield of edible fungus and energy conservation.A wireless temperature-humidity monitoring system is established in a flammulina velutipes mushroom house, which is located in Fengxian District, Shanghai City. CFD software is applied in the numerical simulation analysis and experimental study on the mushroom internal environment. Then adding the return air inlet and changing the air supply angle of fan are used to realize the optimization of internal environment. The main content of the research work is as follows:(1) Based on the basic analysis of CFD simulation theory of mushroom house,mathematical models are established to describe the two different cases of single phase gas and multiphase gas.(2) By using CFD software model of simulation on the mushroom house is established. Using the standard k-ε turbulence model and the semi implicit algorithm of SIMPLEC to simulate the indoor temperature field, humidity field and CO2 gas concentration field of the mushroom house. The simulation results were compared with thetest results to verify the validity and the accuracy of simulation model.(3) The mushroom house temperature-humidity real-time monitoring system is established with LabVIEW software and Zig Bee wireless transmission technology to monitor of indoor temperature-humidity at the different measured locations.The temperature-humidity changes in interal mushroom house have been observed and recorded when fan and a humidifier is operated successively, providing experimental reference data to verify the validation of CFD simulations.(4)It is used to optimize the mushroom house structure by adding return air inlets and changing the send wind angle. The results show that: temperature, humidity, CO2 gas concentration distribution of the optimized mushroom house is more uniformity and stability.(5) It is obtained from the simulation results under the condition of adding return air inlets and changing the send wind angle that the mushroom house environment achieved the optimal state and promoted the growth of the Flammulina velutipes after the operation of the humidifier.