Research On The Strength And Flow Field Temperature Field Of Photovoltaic Light Steel Greenhouse Based On Finite Element Analysis

Photovoltaic light steel agricultural greenhouse,which combines photovoltaic power generation module with agricultural greenhouse,is a new type of product developed according to market demand.It achieves power generation on the greenhouse and planting under the greenhouse,and has advantages of good anticorrosion and low cost.But the structure is complex.Because it needs to be generalized throughout the country,it must be designed in consideration of wind and snow resistance of support and the flow field temperature field in the greenhouse.To solve the above problems,the thesis checks whether the design of photovoltaic light steel greenhouse is reasonable and whether the environment in the greenhouse is suitable for crop growth through finite element simulation method.The specific research content and conclusions are as follows.In Chapter 2,we systemically analyze the strength of the steel structure of photovoltaic agricultural greenhouse by the finite element method.For the safety of the whole structure,we study the overall force and component deformation of photovoltaic matrix under wind load,snow load and constant load.It is found that the overall structural strength of the bracket is relatively safe under force 8 wind(20.7m/s),and the local area has a phenomenon of stress concentration.Furthermore,the overall structural strength of the bracket is safe under the heavy snow once in thirty years(snow load of 0.19 kN/m2).In Chapter 3,we give the structural dynamics analysis of the steel structure of photovoltaic agricultural greenhouse using the finite element method.We also study the wind resistance of the photovoltaic light steel greenhouse under fluctuating wind conditions.It is shown that the deformation and stress of light steel boron structure under fluctuating wind are 1.33 times and 1.15 times of those under static state respectively.Under the condition of 10?11 wind speed,the structure has the problem of insufficient strength,and the purlin and photovoltaic bracket may be broken.To deal with these problems,we suggest some corresponding solutions,which provide theoretical basis for the actual design and production.In Chapter 4,we simulate the flow field and temperature field inside the photovoltaic light steel greenhouse using the finite element method.We study the influence of the building on the flow field distribution and changes on the temperature distribution in the greenhouse,and compare with the actual test results.The simulation results can better reflect the temperature distribution and changes on the temperature in the greenhouse,which can effectively guide the installation position and angle,and opening time of the fan and the opening position of the top exhaust window.Moreover,these results provide reference for crop planting in greenhouse and ensure the safety and stability of photovoltaic system.Through this research,we verify that the photovoltaic light steel agricultural greenhouse is safe under force 8 wind,and the temperature and humidity of indoor can satisfy the growth needs of plants by fan-cooling.