共查询到18条相似文献,搜索用时 140 毫秒
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热风循环温控系统主要应用于干燥炉中,为被干燥对象提供所需的高品质温控环境。目前,大多数干燥炉的温度控制偏差在5℃以上,同时热气流不均匀造成不同区域的干燥效果不尽相同。通过对以往干燥炉温控系统的总结与优化,提出了一种更为精确、全面的控制方案。该热风循环温控系统主要包括温控系统与风机系统两大部分,通过优化的温控算法整合成PID 温控调节模块以实现温度的快速准确响应;同时引入风机系统,优化机械结构设计来改善气流的均匀性。通过温控系统与风机系统的有效整合,实现了分布均匀、温度可控的干燥环境。经过实际测试使用,该系统达到了设计要求,为干燥炉中温控系统的设计提供了一种可靠地选择。 相似文献
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为了能够更精确、更省时地采集污泥热风干燥过程的相关参数,我们研制了一套基于MATLAB/Simulink和组态王的监视平台.该监视平台利用通用的数据采集卡和传感器,实现了同时监视和记录污泥干燥过程中的重量、风速、温度、湿度、设备耗电量等参数,同时利用MATLAB强大的计算功能,计算出污泥干燥速率、污泥水分扩散系数、MR曲线等.本文主要介绍了该监视平台的构成情况以及在污泥热风干燥中的应用,实践证明该监视平台的可行性和有效性,值得推广. 相似文献
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刘军涛 《电子工业专用设备》2013,(7):57-60
偏光片消泡设备的作用是对贴附好偏光片的液晶玻盒进行处理,提高显示质量,腔体内部温度均匀性是其关键性能指标之一,腔体内部热风循环系统是保证设备工作过程中温度均匀性的结构。通过对该部分结构的详细分析,确定有效可行的机械结构,并根据计算得出的结构在设备上进行试验,得出实验数据,最终实现对温度的精确控制。 相似文献
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微波加热作为一种清洁又高效的加热方式,已普遍应用于化工、医药、冶金以及食品加热等多个方面,而如何提高微波加热的均匀性一直是近些年来研究的热点。本文通过分别对比旋转和变频对微波加热均匀性的影响,提出一种旋转变频的新型微波加热技术,同时使用多物理场仿真软件COMSOL仿真计算,结果表明采用频率范围在2.4~2.5 GHz变化的旋转变频式加热方式,温度变化系数降低了0.33,并进行了实验验证。实验结果和仿真计算结果相一致,证实了旋转变频式加热技术有利于提高微波加热的均匀性。 相似文献
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自新冠肺炎疫情爆发以来,各行各业对消毒灭菌的要求越来越高,因此开展微波灭菌技术的研究意义重大。传统的微波灭菌技术中由于固体培养基存在受热不均匀的问题,导致出现灭菌“冷点”,灭菌时间过长。文章首先对微波辐射腔的电场分布特性和固体培养基的温度分布特性进行了仿真研究。研究结果表明:微波辐射腔内的电场分布呈现馈源较近区域内场强大于较远区域内场强的特点,固体培养基的温度呈现出四周高于中心位置的特征。然后采用在辐射腔内添加搅拌器的措施,有效改善了腔体内部的电场分布和培养基的温度分布特性。最后通过微波灭菌试验证明了搅拌器能显著改善微波灭菌中的受热不均匀问题,提高了灭菌率。 相似文献
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Michele N Berteli Antonio Júnior Marsaioli Elisabeth Rodier 《The Journal of microwave power and electromagnetic energy》2007,40(4):241-250
Drying processes have evolved considerably over the years, aiming at the best conditions to shorten the processing time, but maintaining the highest final product quality. The application of vacuums to the microwave drying process might be interesting, especially for thermally sensitive products because the reduced boiling point of the solvent allows a lower temperature processing. The objective of the present work is to study and evaluate the process of drying a granulated product that is the basis of the drug hydrochlorthiazide, with an initial moisture content of 21% in dry basis. This study monitored the drying kinetics, product temperature and power absorbed by the sample using a bench scale vacuum microwave dryer. The equipment consisted of a cylindrical pressure vessel crossed by a wave guide, setting up a system whereby the vacuum pressure, the sample weight and the incident, reflected and residual microwave powers could be measured and evaluated, throughout the entire process. The experimental runs were established with an approximate incident microwave power at 20 W for absolute pressure levels of 50 and 75 mbar, working with samples of about 1.4 g. It was observed that the vacuum microwave process kinetics at both pressure levels showed little difference. The processes were carried out almost entirely in a regime of water evaporation, the product's temperature remaining below the solvent boiling temperature. The drying times were similar for both processes, whereas the absorbed power was slightly higher at the pressure of 75 mbar. 相似文献
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《Microwave Theory and Techniques》1972,20(8):547-549
A combination of hot air and microwave heating is generally achieved by placing air knives alongside the waveguide applicators when drying web materials. lf the air knife is placed inside the applicator, using it as the center conductor of a TEM structure, better or additional moisture removal may be achieved. The TEM mode also permits more control of the wave attenuation. Perturbation formulas are developed to compare conventional slotted waveguide applicators with two TEM systems. Experimental results are given. Improved uniformity of heating and lower leakage are indicated. 相似文献
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微波在煤泥低温脱水提质的应用研究 总被引:1,自引:0,他引:1
利用微波能对煤泥低温脱水提质,探讨了微波干燥的影响因素;分析了微波干燥对煤泥性质的影响;寻求煤泥资源化利用的途径。微波时间、功率和煤泥形状、质量对微波干燥效果影响显著。在微波作用下,煤中水分的蒸发过程分三个阶段:煤加热,外在水分减少,内在水分减少,因而干燥速度较快。烘干重量为200g,水分25%的煤样所需时间不超过700s。试验表明:干燥200s后,煤样温度可达110℃;600s后,温度可达240℃。不仅蒸发了水,也排出了挥发成分。煤泥在微波低温干燥条件下具有较好的脱水效果,干燥后煤泥的含水率和热值提升幅度均达到了预期目标,证明了微波在煤泥干燥提质方面应用的可行性。煤泥微波脱水后,由于微波加热在加热物料内形成的特殊传热传质机理,煤泥内部的矿物盐等会在煤泥表面积聚,形成"硬壳",煤泥不易粉化、破碎,且水分回吸不明显,有助于后续运输和利用。 相似文献
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Viboon Changrue G S Vijaya Raghavan Yvan Gariépy Valérie Orsat 《The Journal of microwave power and electromagnetic energy》2007,41(2):39-47
A laboratory scale microwave vacuum dryer with the ability to record temporal variation of mass and temperature of a drying product was designed and built. The initial study was set up to investigate the effect of the position of a vacuum pressure control valve at two vacuum pressure levels, 6.5 and 13.3 kPa, with a fixed microwave power input of 1.5 W/g. Then, strawberry halves and carrot cubes (10 x 10 x 10 mm) were used for a preliminary study to investigate the effect on drying product temperature and the effect of input microwave powers (1, 1.5 and 2 W/g) at a fixed level of vacuum pressure (6.5 kPa). The position of the valve which allows air to pass through the vacuum container was found to provide shorter drying time and reduced the occurrence of water vapor condensation. The product temperature at the end stage of drying under continuous microwave mode was too high to ensure quality for both dried strawberry halves and carrot cubes. 相似文献
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单伟 《电子工业专用设备》2010,39(4):32-35
提出一种基于WinCE系统的嵌入式窑炉控制系统设计原理和方法。运用自适应模糊PID控制算法对采集到的温度、速度、压力等信号进行运算处理,实现对温度、压力、网带速度等物理量自动控制。该系统硬件平台基于ARM9处理器构建;软件部分采用C++语言实现。 相似文献