This paper presents background, experimental design, and preliminary experimental results for the liquid hydrogen bubble point tests conducted at the Cryogenic Components Cell 7 facility at the NASA Glenn Research Center in Cleveland, Ohio. The purpose of the test series was to investigate the parameters that affect liquid acquisition device (LAD) performance in a liquid hydrogen (LH2) propellant tank, to mitigate risk in the final design of the LAD for the Cryogenic Propellant Storage and Transfer Technology Demonstration Mission, and to provide insight into optimal LAD operation for future LH2 depots. Preliminary test results show an increase in performance and screen retention over the low reference LH2 bubble point value for a 325 2300 screen in three separate ways, thus improving fundamental LH2 LAD performance. By using a finer mesh screen, operating at a colder liquid temperature, and pressurizing with a noncondensible pressurant gas, a significant increase in margin is achieved in bubble point pressure for LH2 screen channel LADs.

关键词：液态电池；电能利用；电能存储

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This project, ACRP Project 11-03, Synthesis of Information Related to Airport Practices, searches out and synthesizes useful knowledge from all available sources and prepares concise, documented reports on specific topics. Reports from this endeavor constitute an ACRP report series, Synthesis of Airport Practice. This synthesis series reports on current knowledge and practice, in a compact format, without the detailed directions usually found in handbooks or design manuals. Each report in the series provides a compendium of the best knowledge available on those measures found to be the most successful in resolving specific problems.

关键词：电池；电动汽车；环保能源

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为了降低燃煤电厂汞污染物的排放量,基于量子化学的密度泛函理论(DFT)构建了活性炭纤维(ACF)平行四碳环模型,以研究不同含氧官能团对ACF表面吸附单质汞(Hg0)机理的影响.理论计算结果表明:2个位于相邻或相近活性位含同一含氧官能团的ACF表面吸附Hg0的吸附能基本相同;内酯、羰基和半醌官能团使ACF表面对Hg0的吸附为化学吸附;羧基、酚羟基官能团则抑制ACF表面对Hg0的吸附;理论计算结果与试验结果一致,表明密度泛函理论是研究汞吸附性能的一种有效方法。

关键词：密度泛函理论；汞吸附；活性炭纤维；含氧官能团；活性炭；活性位

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蓄热堆积床是否具有高效蓄、放热能力是太阳能热发电技术的关键.根据高温蓄热球与载热流体间的能量平衡,考虑载热流体与蓄热球之间的换热系数,以及相变材料密度的变化,建立了堆积床放热过程的数学模型,并进行了数值模拟,讨论了载热流体流速、相变材料初温、蓄热球半径和孔隙率对蓄热堆积床放热过程的影响.结果表明:载热流体流速越快,蓄热堆积床放热速率越大;孔隙率越小,越不利于蓄热单元散热,但对堆积床整体放热和蓄热有利;相变材料初温仅对显热放热阶段有影响,降低初温,可缩短整体放热时间;蓄热球半径越小,蓄热堆积床放热速率越快,蓄热量也越大。

关键词：太阳能热发电；蓄热堆积床；高温蓄热球；载热流体；放热速率；换热系数

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The charging station of battery replaceable EV is used as measures for voltage control for a distribution network with large penetration of PVs. Stochastic optimal operation method of the charging station which maintains voltage of a distribution network and can replace batteries is studied. In addition, the battery usage fee is evaluated to get incentive to both EV users and the charging station to demonstrate usefulness of battery replaceable EV.

关键词：光伏；分销网络；电压控制

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以某1000MW机组汽轮机末级叶片为对象,采用CFX软件对该汽轮机末两级叶栅内凝结流动及水滴沉积过程进行了数值模拟,计算分析了除湿缝的缝隙位置、角度、宽度及数目对除湿效率、二次水滴去除率和级效率的影响.结果表明:为保证末级叶片同时具有较好的除湿性能、级效率和静叶刚度,除湿缝结构应设计在相对叶高60%以上,且在压力面和吸力面相对叶宽80.6%和29.2%处;除湿缝角度选取45°,除湿缝宽度采用1.0mm;若不考虑空心静叶的强度问题,单段除湿缝的综合性能更优;当开缝面积相同时,双缝除湿缝的各项性能均更优;当开缝宽度相同时,单缝除湿缝的综合性能更优。

关键词：1000MW机组；汽轮机；末级叶片；空心静叶；除湿；缝隙结构；数值模拟

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目前,我国电站锅炉回转式空气预热器(空预器)普遍存在漏风率较高、运行可靠性较低等问题.空预器的密封型式是决定其漏风率的关键因素.为此,对回转式空预器的不同密封型式进行了详细介绍和比较.从实际应用效果来看:空预器采用多密封技术配以可调式密封系统,其漏风率较低;采用柔性密封技术后及时进行检修更换,也能将漏风率控制在较低水平;间隙自补偿密封、疏导密封和加压密封目前应用较少,其可靠性及应用效果仍需观察。

关键词：回转式；空气预热器；密封技术；漏风率；可靠性

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The Virtual synchronous generator (VSG) is an inverter based generating unit that uses a synchronous generator model to insert virtual inertia to power system. In this research, the parameters of the VSGs of the multi-VSG system are tuned to obtain the desired response. First, the multi-VSG microgrid is introduced. Then Particle Swarm Optimization is implemented to tune the parameters of the VSG units in the microgrid. Further, the virtual inertia control is applied to the VSG units to improve its stabilization. The simulations in PS CAD are represented for three conditions of VSG parameters and the results are compared.

关键词：微电网；智能电网；虚拟同步发电机

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The TIG arc welding is the high-quality joining technology. However, the weld pool is shallow in the TIG welding because the heat transfer to anode is poor. So, the weld defect sometimes occurs. The pulsed arc welding and mixing oxygen are used in order to control the heat transfer and prevent the weld defect. However, few reports has reported the variation of heat transfer to anode and the physical arc phenomena. In this paper, the time variation of heat transfer to anode in pulsed arc welding mixed with oxygen was elucidated in order to know the welding depth for prevention of welding defect. The thermal conductivity of heat transfer in the case of pulsed arc is not same as that in the case of stable arc. The thermal conductivity of heat transfer gradually decreases with increasing the time. The thermal conductivity of heat transfer can not catch up with the current waveform. When the arc is the transient mode, the arc radius and temperature distribution can not catch up with the stable arc ones. However, the heat transfer from center to r=3.00 mm can catch up current waveform. Thus, the thermal conduction of heat transfer varies over r=3.00 mm. The variation of it with Ar-O_2 is larger than that with pure Ar. Because the specific heat increases, the arc temperature at center becomes high.

关键词：电弧焊；脉冲电弧；传播热量；电磁热流体仿真

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采用CFD Fluent6.3软件模拟了自主研发的低阶煤低温干馏炉对喷式低温燃烧室内温度场分布,并对其结构进行了优化.结果表明:在燃烧室内设计4个关于燃烧室中央轴对称的长度分别为800mm和500mm、旋转角度分别为±30°和±10°的直挡板后,燃烧室内横向、纵向平均温度满足褐煤低温热解需求(500~650℃);采用非预混模式、过量空气系数为1.25和煤气管径为50mm时,燃烧室的燃烧特性最佳;过量空气系数、煤气与空气预混方式、管径均会影响燃烧室内温度分布;Realizablek-ε湍流模型、P-1辐射模型和非预混燃烧模型适用于计算焦炉煤气和空气低温燃烧室内燃烧温度场分布;模拟计算结果与实验结果基本吻合,误差波动幅度为50~70℃,同时对燃烧后烟气的检测结果表明,烟气排放符合标准要求。

关键词：低阶粉煤；低温干馏炉；低温燃烧室；NOx排放；CFD模拟

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