Research On Unsteady Numerical Simulation Of Influence Of Solar Radiation To Environment Parameters In Phytotron

This article taken the desert environment phytotron as the object, it used the methods of numerical simulation and experiment to research influence of solar radiation to the environment parameters in phytotron. The method of numerical simulation was feasible to analyze the indoor temperature field,velocity field and distribution of floor solar radiation.This section of numerical simulation carried on the Computational Fluid Mechanics software FLUENT and established the model of Realizable k-εto research this project. When the grids were built, for the sake of reduce the node, save the iterative time, and guarantee the computational accuracy in mainstream region, it used the composite zoning grid's technology. First, it compared the characteristic and applicability of different radiation model. Second, through changed sunlight simulator's altitude and numbers it simulated the different solar radiation, and carried on the steady numerical simulation. Finally, selected November 8, 2007 9:00-16:00 and someday (August 16) which solar radiation was strongest in Typical Meteorological Year to research influence of glazed roof and sunlight simulator to environment parameters in phytotron. In experiment aspect, selected the indoor characteristic section, and carries on the points of measurement in the section, obtains the corresponding parameters, then compared the results of numerical simulation and experiment.By analyzing the results of simulation and experiment, DO model was in good agreement with the practice for indoor radiation. When opened the sunlight simulator, with the increased of lamp's altitude, the hot current was more difficult to be carry off and the floor solar radiation value reduced obviously; with the increased of lamp's quantity, the current of indoor upstream was more obvious and the floor solar radiation value elevated obviously. It was propitious to obtain an even radiant illuminance if the lamp arranged as "plum blossom". It was the same effect to indoor heat transfer when turned on group A of lamp or turned on group D. It was the same effect to solar radiation simulation when turned on all lamps or turned on each group of lamps. When closed the sunlight simulator, the disturbance of indoor temperature and velocity mainly caused by capacity of heat transmission permeated from glazed roof; sunlight simulator affected the indoor distribution of temperature field, and had the obvious mask effect to the floor solar radiation. Therefore, it suggested blocking the glazed roof with the insulating material.