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潘地林 《淮南工业学院学报》2011,(3):27-30
射流风机已在公路隧道、铁路隧道及地铁通风中被广为应用。正确的进行射流风机的空气动力设计可以提高通风装置效率,降低隧道通风的运营成本。通过对射流风机的空气动力特性分析,论证了射流风机叶轮所产生的静压仅仅是用于克服风机本身的内部流动阻力,与改善隧道内通风状态无关。指出在进行射流风机空气动力设计时,应使得其叶轮产生的静压尽可能的小。同时,给出了合理设计射流风机的通流部件的具体方法。 相似文献
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积极推进纺织印染业的清洁加工生产,直接关系到行业可持续发展.文章介绍了20世纪70年代以来国内外气雾/气液节水染色技术的发展状况,运用气雾/气液喷射技术是当前纺织丝绸印染业开发高效节水降耗染色新技术、新设备的重要方向. 相似文献
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Jet spreading width is one of the important characteristics of water jets discharging into the air. Many researchers have dealt with measuring this width, and contact measuring methods on the water jet surface were employed in a lot of the cases. In order to avoid undesirable effects caused by the contact on the jet surface, we introduce non-contact measuring methods with a laser instrument to the measurements of jet spreading width. In measurements, a transmitter emits sheet-like laser beam to a receiver. The water jet between the transmitter and the receiver interrupts the laser beam and makes a shadow. The minimum and maximum values of the shadow width are measured. In addition, pictures of the water jet are taken with a scale, and the shadow width is measured from the pictures. The experiments on various needle strokes were performed. Three kinds of width consistent with the jet structure were obtained. In the results, it can be concluded that our non-contact measuring methods are feasible. The data of jet spreading widths and jet taper were obtained and are useful for future applications. 相似文献
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HRJ (Hydro-processed Renewable Jet) conversion technology has been recently used to produce renewable jet fuel for commercial or military flights. In this study, a techno-economic analysis is carried out for evaluating the production of jatropha-derived HRJ fuel through a bio-refinery process. Each component of the chosen feedstock jatropha can be converted into valuable products. The bio-refinery process is split into 6 parts: (1) Fruit Dehulling; (2) Shell Combustion; (3) Oil Extraction; (4) Press Cake Pyrolysis; (5) Oil Upgrading; (6) Product Separation. The minimum jet fuel selling price (MJSP) from this fruit scenario is calculated to be $5.42/gal based on the plant capacity of 2400 metric tonne of feedstock per day. The co-products obtained from the process not only significantly deduct the production cost but make the entire process energy self-sustainable. We also discuss the oil scenario, which oil is the starting material and the process begins from Oil Upgrading section. The oil scenario offers the MJSP of $5.74/gal with lower capital but higher operating costs. The differences of MJSPs for fruit and oil scenarios are due to feedstock cost, refinery capital cost, co-product credits and energy cost. Based on the sensitivity analysis, the feedstock price, oil content, plant capacity, reactor construction and catalyst usage are important parameters that control the price of the produced fuel. 相似文献
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多尾鳍仿生推进器多推进模式运动仿真研究 总被引:1,自引:0,他引:1
提出了一种新型水下仿生推进器,采用多尾鳍协调驱动方式实现了鱼类波动推进模式和水母射流推进模式的有机复合,建立了多尾鳍波动-射流推进的运动学模型,着重利用计算流体动力学方法对多尾鳍波动-射流推进运动进行了仿真分析。研究结果表明:在特定运动参数下,多尾鳍波动推进模式能提供持续均匀的推进力,游动稳定性好;而射流推进模式,能产生瞬间的大推进力,加速性能好。研究内容为进一步探索多模式推进理论提供了依据。 相似文献
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玻璃生产中混合料的主要工艺指标为均匀度、水份和温度。通过应用射流器对原加水系统进仃改造,使混合料加水系统操作简单,质量稳定,维护方便,从而达到稳定混合料的水份和温度这一目标。 相似文献
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Reverse-flow diverter pumps have no moving parts that are in direct contact with the fluid; as a result, they are applicable for the transport of hazardous liquids or liquid–solid mixtures. To date, there is no method available for predicting the pumping capacity of reverse-flow diverter pumps. In this study, we experimentally investigated the pumping performance of reverse-flow diverters in the reverse-flow mode. Two dimensionless performance equations, expressed as q = 0.9597exp(−Eur/0.9237) + 0.4946exp(−Eur/7.360) + 0.1765 and q = kα + I, were determined from the experimental data. Based on these two equations, a method for predicting the pumping capacity of reverse-flow diverter pumps was proposed. 相似文献
30.
借助CFDesign 9.0软件平台,基于有限体积法计算连续相控制方程,结合多相流模型中的流体体积模型以及可实现κ-ε湍流模型,对液体射流泵全流场进行了三维数值模拟。 相似文献