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11.
Xi WU Hong YE Jianxiang WANG Jie HE Jian YANG 《Frontiers of Energy and Power Engineering in China》2012,(2)
The influence of the period of rotation on the effectiveness of the thermophotovoltaic (TPV) rotary regenerator was theoretically and experimentally investigated.It was found that the deviations of the... 相似文献
12.
《International Journal of Hydrogen Energy》2019,44(56):29743-29751
Operational rules and control strategies of the chemically recuperated gas turbine (CRGT) in the marine propulsion are investigated in this paper. The Minimization of Gibbs free energy method is used to calculate the diesel-steam reforming reaction which products synthetic hydrogen rich fuels, and a universal model of the chemical regenerator which is easily applied to different application environments is created. The hydrogen production and hydrogen molar fraction are investigated to verify that the CRGT improve the combustion performances under low working conditions. Off-design calculations are performed to derive proper operational rules, and transient calculations are performed to investigate the best control strategies for the systems. The modelling approach of the chemical regenerator can be generally used in the chemically recuperated gas turbine. The elaborate operational rules can greatly improve the thermal efficiencies under every working condition. The system using synchronous control strategies have better regulation speed and operation stability than that using asynchronous control strategies. 相似文献
13.
In this paper, numerical and experimental investigations on a magnetic refrigeration device based upon the active magnetic regeneration (AMR) cycle operating near room temperature are presented. A numerical 1D model based on the transient energy equations is proposed for modelling the heat exchange between the magnetocaloric material and the carrier fluid in the regenerator bed. The validity of 1D AMR-numerical model is investigated through the recently developed magnetic cooling demonstrator by Clean Cooling Systems SA (CCS) at the University of Applied Sciences of western Switzerland (HES−SO). The obtained results including the temperature span, the coefficient of performance and the cooling power are presented and discussed. In general, good agreements have been noted between the experimental and numerical results. 相似文献
14.
Magnetic refrigeration is an emerging, environment-friendly technology based on a magnetic solid that acts as a refrigerant by magnetocaloric effect. The reference cycle for magnetic refrigeration is AMR (Active Magnetic Regenerative refrigeration). In this paper, attention is directed towards the near-room-temperature range. We compare the energetic performance of a commercial R134a refrigeration plant to that of a magnetic refrigerator working with an AMR cycle. The comparison is carried out by means of a mathematical model. In these simulations, we consider different solid magnetic refrigerants, namely, Gd, Gd0.95Dy0.05, Gd0.9Tb0.1,Gd5Si2Ge2, MnAs0.9Sb0.1, and MnAs0.95Sb0.05. We compared two different geometries of the regenerator: a porous medium and a flat plate. In the former, the Coefficient of Performance (COP) of the AMR cycle is better than that of the vapour compression plant only in the low mass flow-rate range. Whereas in a flat plate regenerator, the COP of the AMR cycle is better than that of the vapour compression plant only in the high mass flow-rate range. 相似文献
15.
120万t/a重油催化裂化装置节能改造效果分析 总被引:1,自引:0,他引:1
由于中国石油哈尔滨石化公司的120万t/a重油催化裂化装置存在主风机出口至烟机入口压降偏高的问题,所以对装置进行了改造。结果表明,改造后新设增压机,提压约40 kPa;用新型烟气分配器取代大孔分布板,实现了第二再生反应器的小风量操作,其主风流量控制在440 m3/min;改造后总能耗为36 kW.h,较改造前降低了247 kW.h;改造后再生反应器内实际烧焦效率达到了39.74%,是改造前的1.76倍。 相似文献
16.
回热器为回热式低温制冷机的关键部件,其性能对系统的影响甚大。为探索回热器内金属丝网混合填充对回热器性能的影响,文章基于回热器模拟软件REGEN3.3仿真结果的基础上,制作了单级脉管制冷装置,采用#300SS,#400SS和#500SS的金属丝网混填了四组回热器,并在不同输入功率下进行了系统制冷性能实验。实验结果表明,较之低目数丝网填充的回热器制冷机,采用高目数丝网填充的回热器制冷机性能较优;在回热器热端填充低目数,冷端填充高目数的丝网,可提高回热器冷端压比,提高整机制冷性能。 相似文献
17.
对中国石油化工股份有限公司九江分公司1.20 Mt/a S Zorb装置再生器下料中断原因进行了分析.提出了处置措施:加强原料和工艺精细化管理,确保汽油含水量维持最低水平;将再生器下料流程,从原设计的再生器锥体底部输送吸附剂至再生滑阀,改为再生器筒体下部斜管下料管线输送至再生滑阀,防止吸附剂结块堵塞管路;清理再生器底部... 相似文献
18.
有效的污染控制是影响微型机械制冷机长寿命运行的关键因素.本文首先分类阐述了机械制冷机内各污染源的产生,然后用直接模拟蒙特卡罗方法与传质扩散方程对制冷机内部管道污染气体的传输扩散进行仿真建模,最后分析了污染气体在蓄冷器的凝结吸附以及其它因素对制冷机性能的影响,并介绍了机械制冷机的污染控制技术以及寿命预测。 相似文献
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