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111.
通过广泛分析国内外对土壤源热泵实验研究的现状,建立了可以模拟多个地区、多种运行工况的土壤源热泵沙箱实验台,并进行了绝热边界工况短期内取热的实验研究。  相似文献   
112.
依据热平衡方法测流量原理研制的热平衡流量计没有任何可动部件,可靠性大大加强,可以代替常用的浮子流量计和涡轮流量计。该仪器的应用为油水井及注聚合物井的流量测试提供了更为有效的手段和方法。  相似文献   
113.
Technology can take many forms from the development of sophisticated electronics to the application of basic procedural principles. Technology transfer can also take several forms, however, in this case, it is the transfer of technological principles between application domains that is of primary interest. This paper presents a framework (the Five ‘M’s framework) that can be used to consider the likely success of technology transfer. The framework is based upon a sociotechnical system approach. The framework is illustrated with an evaluation of the introduction of intelligent cruise control into motor vehicles. It is argued that this is a technological concept first developed as an aerospace application in the form of the autopilot. In this case, it is argued that the transfer of this technology in its current form may potentially compromise safety.  相似文献   
114.
通过对焊接工艺及焊后热处理工艺优化,采用摩擦焊接技术对报废抽油杆中仍有使用寿命的杆头与杆体进行了拼接,获得了性能达标的抽油杆。从而提高了旧杆的修复率.降低了采油成本。该技术可在抽油杆修复及相关行业进行推广应用。  相似文献   
115.
我国风机盘管技术现状分析   总被引:2,自引:2,他引:0  
介绍了近年来我国在风机盘管技术领域的最新成果,在结构形式、强化传热、提高室内空气品质、降低噪音和提高自动控制水平等方面的技术进展情况,分析了目前风机盘管中存在的问题,并对今后的发展方向进行了展望。  相似文献   
116.
Some substituted coumarins have been synthesized by von-Pechmann condensation using SnCl2 · 2H2O (10 mol %) as catalyst in ethanolic medium. The reactions are simple, easy in handling and environmentally benign.  相似文献   
117.
Gas-to-liquids (GTL) technology involves the conversion of natural gas to liquid hydrocarbons. In this article, theoretical studies have been presented to determine the feasibility of transporting GTL products through the Trans-Alaska Pipeline System (TAPS). To successfully transport GTL through TAPS, heat loss along the route must be carefully determined. This study presents heat transfer and fluid dynamic calculations to evaluate this feasibility. Because of heat loss, the fluid temperature decreases in the direction of flow and this affects the fluid properties, which in turn influence convection coefficient and pumping power requirements. The temperature and heat loss distribution along the pipeline at different locations have been calculated. Fairly good agreement with measured oil temperatures is observed. The powers required to pump crude oil and GTL individually, against various losses have been calculated. Two GTL transportation modes have been considered; one as a pure stream of GTL and the second as a commingled mixture with crude oil. These results show that the pumping power and heat loss for GTL are less than that of the crude oil for the same volumetric flow rate. Therefore, GTL can be transported through TAPS using existing equipment at pump stations.  相似文献   
118.
This paper presents the mass transfer results from an impinging liquid jet to a rotating disk. The mass transfer coefficients were measured using the electrochemical limiting diffusion current technique (ELDCT). Rotational Reynolds number (Rer) in the range of 3.4 × 104–1.2 × 105, jet Reynolds number (Rej) 1.7 × 104–5.3 × 104 and non-dimensional jet-to-disk spacing (H/d) 2–8 were taken into consideration as parameters. It was found that the jet impingement resulted in a substantial enhancement in the mass transfer compared to the case of the rotating disk without jet.  相似文献   
119.
刘利平  马晓建  陈现玉 《冶金能源》2003,22(4):25-29,49
提出了一种管内装元件强化传热的技术经济评价方法,此方法综合考虑了强化换热器管内传热膜系数的提高和管内流体阻力的增大,与普通的管壳式换热器相比,所带来的投资费用和使用费用变化,这个变化量可用净现值增量△NPV来表示。根据△NPV值来评价强化传热技术,从而为强化传热技术的开发和推广及进行决策提供指导。  相似文献   
120.
This is part II of a study reported earlier on a method to characterize the air flow and water removal characteristics during vacuum dewatering. This article presents experimental data and analysis of results from the use of a cyclically actuated vacuum dewatering device for removing moisture from wetted porous materials such as paper with the intermittent application of vacuum and accompanying air flow though the material. Results presented include sheet moisture content as a function of residence time and hence water removal rate under a variety of process conditions. Also, experimental results on air flow through the wet porous structure and hence the role and importance of air flow during vacuum dewatering are presented. Vacuum dewatering process conditions include exit solids content between 11 and 20% solid under applied vacuum conditions of 13.5 to 67.7 kPa (4 to 20 in. Hg). Regression analysis indicated that the exit sheet moisture content exhibited a nonlinear relationship with residence time with exit solids reaching a plateau after a certain residence time. Final moisture content correlated linearly with the average overall flow rate of air through the paper sample and the basis weight of the material.  相似文献   
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