The Research On The Grain Heap Thermal Transfer Model

Grain safe storage related to the development and stability of the overall situation of thenational economy. Therefore, in the case of internal heat resource in the stored grain bulk,research on the grain heap thermal transfer model, effective control of the granarytemperature and humidity, can achieve the safe and green storage of the grain bulk.In this paper, on the basis of previous studies the theory and technology of the grain bulktemperature mathematical model, based on the theoretical computational fluid dynamics andheat and mass transfer in porous media theory, using the combination of the experiments andCFD simulation method, in Xingyang large warehouse for example, the numerical simulationof granary in the case of adding internal heat source within the variation of temperature andhumidity, the main research contents are as follows:First of all, on the basis of the study of computational fluid dynamics, according to theporous medium heat transfer characteristics of grain bulk，put forward the feasibility of usingCFD method to numerical simulation, analysis the research and the progress in this field ofhome and abroad and the application development status of this software.Secondly, based on the computational fluid dynamics theory, put an internal heat source inthe grain to generate heat, establishing the heat source in the grain under the condition of theinternal heat transfer mathematic model, using FLUENT fluid simulation method, afterseveral numerical gets the basic rule of the heat transfer under the condition of inner heatsource iteration.Finally, in Xingyang grain depot granary for example, by using numerical simulationmethod, establishing the three-dimensional dynamic physical model, selecting the porousmedia, given the state of the airflow and thermal boundary conditions, and using intelligentventilation grain condition detection system, collecting temperature and humidity values inthe case of having an internal heat source in the grain, by compared with experimental dataand simulation data to verify the accuracy of the establishment mathematical model.Research results show that compared through theoretical analysis and experimental validation, and proved that this paper establish mathematic model is correct, and also laid thefoundation for the optimization design of the granary warehouse type, provides a new thoughtand method, and it has a great significance for popularization.