【作者】 付剑波；

【导师】 吴静怡；

【作者基本信息】 上海交通大学 ， 制冷与低温工程， 2007， 硕士

【摘要】 低温储粮是最有发展前景的绿色储粮技术之一。现有的自然低温储藏、冬季自然冷源机械通风冷却以及谷物冷却机机械制冷通风冷却,均无法满足“高质量、高效益、低能耗、低污染”的绿色低温储粮要求。新型低温储粮技术的研究开发,是当前粮食储藏技术发展的迫切要求。太阳能是清洁环保、来源广阔的可再生能源。太阳能制冷具有制冷量与制冷需求在时间与地域上的分布高度吻合的特点。国内外对于太阳能吸附式制冷的研究与应用已经有一定的基础,但是在低温稻谷储藏领域的应用尚无先例。基于此,本文开展了太阳能制冷低温稻谷储藏实验研究,具体研究工作如下:(1)对位于江苏中部地区某粮库内的一座粮仓,进行了实验测试,研究其在常规储粮方式下全年仓储粮温的变化规律。在此基础上,提出了四种可行的太阳能制冷低温稻谷储藏通风冷却方式。(2) 2004-2006年,在该粮库采用其中三种通风冷却方式,分别构建了三套不同型式的太阳能制冷低温稻谷储藏系统,并对其进行了实验研究。其中,2006年负责系统的构建与实验测试,2004及2005年参与系统的构建与实验测试。这三套系统分别是:空气隔离层环流通风太阳能制冷低温稻谷储藏系统(2004年),膜下上层与沿墙四周区域内循环通风太阳能制冷低温稻谷储藏系统(2005年),及膜下上层横向双向内循环通风太阳能制冷低温稻谷储藏系统(2006年)。(3)重点对2006年膜下上层横向双向内循环通风太阳能制冷低温稻谷储藏系统进行了实验研究。实验研究的主要内容有:对太阳能吸附式制冷子系统的性能及匹配进行了分析;完成了太阳能制冷低温稻谷储藏实仓实验,分析了系统在实际运行中的储粮效果,并对粮堆“冷心”冷量的利用以及通风冷却方式进行了探讨。(4)对2004-2006年三套不同型式的太阳能制冷低温稻谷储藏系统,从太阳能吸附式制冷子系统性能以及储粮效果两方面进行了比较,寻找出其中性能及效果最好的一个,作为今后后续深入研究的基础。对这三套太阳能制冷低温稻谷储藏系统的实验研究及分析比较表明,与仅采用常规储粮方法的对照仓相比,实验仓在高温季节能对粮堆的上层及沿墙四周区域粮温起到一定的抑制作用,延缓粮食陈化,改善储粮效果。其中,膜下上层与沿墙四周区域内循环通风太阳能制冷低温稻谷储藏系统的性能及效果最佳,如能在上层粮温上升到15-20℃之前投入运行,有望实现稻谷的准低温储藏。更多还原

【Abstract】 Grain is one of the basic backbones for every country, and grain storage is necessary to ensure their security in grain supply. Low-temperature grain storage is one of the most promising technologies in grain storage. Nowadays, the development and utilization of low-temperature grain storage in our country is not satisfying. The importance of low-temperature grain storage is not so well understood, and the existing technologies have not met the requirements of high quality, high benefits, low energy consuming and low pollution, including: grain storage under natural low temperature, mechanical ventilation in winter using natural cold source and mechanical refrigeration with a grain cooler. There are great needs for novel low-temperature grain storage technologies. Solar energy is the energy which is clean, environment friendly and renewable. Solar cooling has the advantages that its cooling power and cooling demand can match well both with time and location. There have been some utilizations and researches in solar driven adsorption refrigeration, but it has not been reported that using solar adsorption chiller in low-temperature grain storage, which is right the research of this paper. The main research work of this paper can be summarized as following:(1) The grain temperature distribution in a grain bin all over one year was investigated, based on which four types of feasible ventilation mode for low-temperature grain storage with solar cooling were brought out. The grain bin was located in Jiangsu Province, where the solar irradiation is at the moderate level of China.(2) From 2004 to 2006, three sets of low-temperature grain storage system with solar cooling were built in three grain bins respectively. They were: low-temperature grain storage system with solar cooling plus circulating ventilation in an air insulation layer, low-temperature grain storage system with solar cooling plus internal circulating ventilation in the top layer and the area close to the wall under the sealing film, and low-temperature grain storage system with solar cooling plus internal and bidirectional circulating ventilation in the top layer under the sealing film. Among them, the system built in 2006 is the main research point of this paper.(3) The experimental study in this paper was mainly carried out on the system built in 2006, including: analysis of performances of the solar adsorption refrigeration subsystemand matching between its components; the low-temperature grain storage system was tested in practice, from which the effect of grain storage was investigated. The utilization of cold core of the grain bin and the ventilation mode were also discussed.(4) The performances and effects in grain storage of the three systems from 2004 to 2006 were compared, in order to find the system with the best performances and effects in grain storage, to be the basis of the following advanced study in the future. The experimental study carried out in 2004-2006 indicated that using the above three low-temperature grain storage systems with solar cooling can delay or restrain the going up of the temperature in the top layer and the area close to the wall of the experimental bins in some degrees during hot months, compared to their reference bins. Among them, the low-temperature grain storage system with solar cooling plus internal circulating ventilation in the top layer and the area close to the wall under the film, gave out the best performances. If the system starts to work before the temperature of the top layer goes beyond 15-20℃, it is quite probable to reach the goal of quasi-low-temperature grain storage.更多还原