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空气能热泵烘干房温度场、风速场仿真分析
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Abstract:
干燥行业是我国工业能耗的大户,热泵及除湿干燥技术因其能效比高、环境友好并能较好地保持物料的品质而越来越受到重视,其在不同种类的物料烘干中都有成熟的应用。本文所研究的空气能热泵烘干设备主要应用于畜禽粪以及污泥烘干领域,在空气能热泵烘干房热源不变的情况下,借助Solid Works的Flow Simulation模块来分析不同风道布置下烘干房内温度场、风速场的分布情况,旨在改善物料表层的干燥环境,提高设备热利用率。首先,将方案一中温度场的模拟结果和实测结果进行了对比分析,发现相对误差在5%以内,证实了模拟结果的可靠性。其次,进行了方案二中温度场和风速场的模拟。通过仿真发现,在设备原有结构基础上加装了顶部对向轴流风机和导风板对风速场的改善效果不明显,但对温度场的改善较为明显。加装后,一、二层物料表面的温度有所提高,大大减小了一、二层物料沿宽度方向的温差,物料表面整体温度值有所提高且温度场分布均匀性得到提升。考虑到温度对对流干燥的影响程度大于风速,且方案二对温度场的改善较为明显,故设备选择采用方案二的风道结构。该仿真分析方法对设计和改进烘干房风道结构及风机布置具有一定的指导意义。
The drying industry is a major energy consumer in China, and heat pump and dehumidification drying technology have been paid more and more attention because of their high energy efficiency ratio, environmental friendliness and better maintenance of material quality, it has been widely used in drying different kinds of materials. The air energy heat pump drying equipment studied in this paper is mainly used in the field of livestock and poultry manure drying and sludge drying, the distribution of temperature field and wind velocity field in the drying room with different air duct layout is analyzed by using the Flow Simulation module of Solid Works, in order to improve the drying environment of material surface and the heat utilization ratio of equipment. Firstly, the simulation results of the temperature field in scheme 1 are compared with the measured results, and the relative error is less than 5%, which proves the reliability of the simulation results. Secondly, the temperature field and wind velocity field in the second scheme are simulated. Through simulation, it is found that the improvement effect of the wind speed field is not obvious when the axial flow fan and the wind guide plate are added to the original structure of the equipment,but the improvement of temperature field is obvious. After installation, the surface temperature of the first and second layers is increased, and the temperature difference along the width direction of the first and second layers is greatly reduced. Considering the effect of temperature on convective drying is more than wind speed, and the improvement of temperature field is obvious in scheme 2, the air duct structure of scheme 2 is chosen. The simulation analysis method has certain guiding significance for the design and improvement of air duct structure and fan arrangement of drying room.
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