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1.
代永朝  董玉祥 《粘接》2003,24(2):34-35
分析了飞机油箱的漏油原因,介绍了油箱渗漏标准和修理要求,对密封胶配制和粘接修理工艺进行了研究,并给出了修补验证结果,修复48h后进行压力密封试验,均不渗漏。  相似文献   

2.
C. Wieser 《Fuel Cells》2004,4(4):245-250
During the past few years, the feasibility of using polymer electrolyte fuel cells in automotive power trains at an impressive performance level has been proven repeatedly. However, current fuel cell stacks are still largely based on decade‐old polymer electrolyte membrane technology thus limiting performance, durability, reliability, and cost of the fuel cell systems. The major challenge for membrane R&D constitutes the demand for polymer electrolytes that allow for system operation at higher temperatures and lower water management requirements without increased conduction losses. None the less, demanding automotive requirements will not compromise on other properties such as mechanical and chemical stability and gas permeability.  相似文献   

3.
整体油箱具有载油量大、质量轻等特点而被各型飞机广泛采用,其内表面需采用特别的密封防腐涂层系统,以保证整体油箱具有较高的“三防”能力和密封性能,提高整体油箱的可靠性和长寿命。本文参照整体油箱材料配套性能中的试验设计,研究了飞机拟采用的 454-4-1防腐涂料与国内燃油以及与 HM113B-4、HM116C-8密封剂的配套相容性。试验结果表明: 454-4-1涂层具有良好的耐水性、耐盐水和燃油性以及耐 15号航空液压油性。 454-4-1涂料与 HM116C-8和 HM113B-4密封剂表面具有良好的粘接力。阳极化的铝合金 +454-4-1涂料 +NJD-3底涂 +HM116C-8/HM113B-4密封剂组成的整体油箱密封体系,材料之间相容性较好,可满足涂层体系各层间粘附性要求。  相似文献   

4.
为满足现代飞机燃油系统模拟试验燃油流量高精度、快速度的测量要求,针对涡轮流量计不能长期保持校准曲线和破坏管路系统的缺陷,提出了超声波测试技术。重点介绍了超声波系统的技术要求、主要功能、工作原理、工作模式和实际测量情况,并结合燃油系统试验进行了对比检验。结果表明:该测试方法满足飞机燃油试验需要,主要设备具有高可靠性、可控性和稳定性,可实现燃油系统的无损测试。  相似文献   

5.
马彦峰 《广东化工》2011,38(7):229-230,264
文章介绍了有机热载体炉供热系统的设计要点.从导热油类型的选择,热量的核算,有机热载体炉主机的选型、辅机的设计,导热油供热系统工艺流程的设计,详细分析了有机热载体炉供热系统、排气系统、冷油置换系统、膨胀槽系统、储油及注油系统、稳压旁路系统、管道流速的设计要求,提出了工程设计时应注意的问题。  相似文献   

6.
P. Kazempoor  V. Dorer  F. Ommi 《Fuel Cells》2010,10(6):1074-1094
Models of fuel cell based combined heat and power systems, used in building energy performance simulation codes, are often based on simple black or grey box models. To model a specific device, input data from experiments are often required for calibration. This paper presents an approach for the theoretical derivation of such data. A generic solid oxide fuel cell (SOFC) system model is described that is specifically developed for the evaluation of building integrated co‐ or polygeneration. First, a detailed computational cell model is developed for a planar SOFC and validated with available numerical and experimental data for intermediate and high temperature SOFCs with internal reforming (IT‐DIR and HT‐DIR). Results of sensitivity analyses on fuel utilisation and air excess ratio are given. Second, the cell model is extended to the stack model, considering stack pressure losses and the radiative heat transfer effect from the stack to the air flow. Third, two system designs based on the IT‐DIR and HT‐DIR SOFCs are modelled. Electric and CHP efficiencies are given for the two systems, as well as performance characteristics, to be used in simulations of building integrated co‐ and polygeneration systems.  相似文献   

7.
To prevent the catalysts in fuel cell systems from poisoning by sulfur containing substances the fuel to be used must be desulfurized to a maximum of 10 ppm of sulfur. Thereby, damage to the catalysts in the fuel cell and the reformer can be avoided. Diesel fuel for road vehicles within the EU is already desulfurized at the refinery. However, jet fuel is permitted to have up to 3000 ppm of sulfur. Since the hydrodesulfurization process used in refineries is not suitable for mobile applications, the aim of the present work was to develop an alternative desulfurization process for jet fuel and to determine its technical feasibility.To this end, many processes were assessed with respect to their application in fuel cell based auxiliary power units (APUs). Among them, hydrodesulfurization with pre-saturation was selected for detailed investigations. Laboratory tests revealed that also syngas operation is possible without any performance loss in comparison to operation with hydrogen. Pure hydrogen is not available in a fuel cell system based on reforming of jet fuel. The effects of reaction temperature, operating pressure and liquid hourly space velocity (LHSV) were investigated. Different jet fuel qualities with up to 3000 ppm of sulfur were desulfurized to a level of 15-22 ppm.Finally, the technical applicability of hydrodesulfurization with pre-saturation was demonstrated in a pilot plant with an electrical power of 5 kW, going beyond the laboratory scale. In a 200-h experiment, a commercial jet fuel with 712 ppm of sulfur was desulfurized to a maximum sulfur content of 10 ppm. Besides this, H2S separation by stripping with air turned out to be a suitable method for APU applications. The aim of developing a suitable process for the desulfurization of jet fuel in fuel cell APUs has thus been achieved.  相似文献   

8.
Low temperature fuel cells such as the Polymer Electrolyte Fuel Cell (PEFC) are preferably used for domestic applications because of their moderate operating conditions. Using the existing distribution system, natural gas is used as a source for a hydrogen rich gas to power this fuel cell type. The high requirements on the fuel gas quality as well as high conversion efficiencies for the small local gas processing units are critical aspects in the evaluation of decentralized fuel cell systems. In the present paper, three typical gas processing methods are evaluated for the supply of a hydrogen rich gas for PEFCs: steam reforming, partial oxidation, and autothermic conversion. All three processes are studied in detail by varying the relevant process parameters: temperature, pressure, steam to fuel ratio, and oxygen to fuel ratio. The results are graphically displayed in numerous nomograms. With the help of these graphs, regions of stable operation and the sensitivity to the operational parameters are discussed. For all three gas processing methods, the graphs generated display methane conversion, the hydrogen yield, and the yields of unwanted components, i.e., carbon monoxide and solid carbon. Although only steady‐state operating conditions were simulated, critical modes of operation, which might occur during start‐up or transient operation can easily be identified. For instance, operating conditions where soot is generated have to be avoided under all circumstances. All simulations were done with the Gibb's reactor model of a commercial simulation program. The Gibb's reactor model was found to be a suitable tool, since the simulated results compared well with reported literature data. According to the simulation results, the methane‐steam‐reforming process appears to be favorable for application to PEFCs. Methane conversion and hydrogen yields are highest for this process while the yield of CO is relatively low.  相似文献   

9.
In the framework of the EC project STORHY (Hydrogen Storage for Automotive Applications), the prototype of a solid storage tank for hydrogen based on sodium alanate was developed. A storage tank containing 8 kg sodium alanate was designed and manufactured with the objective of fast refueling. To obtain the optimum design of the storage tank a simulation tool was developed and validated by experiments with a laboratory‐scale tubular reactor. Application of the simulation tool to different storage concepts and geometries yielded the final design. The chosen concept is modular, enabling simple scale‐up. This is the basis for the future development of fuel cell vehicle storage tanks containing 5 kg of hydrogen.  相似文献   

10.
考虑飞行器的服役环境以及热管理系统质量与几何尺寸的设计要求,探讨了以航空燃料再生冷却技术为基础的高超声速飞行器综合热管理系统的方案。根据不同的热载荷种类和换热方式,结合新提出的超临界压力碳氢燃料管内传热关联式,给出了飞行器热管理系统中两种类型换热设备的传热参数设计方法。利用MATLAB/SIMULINK平台的图形化交互界面创建并封装了飞行器热管理系统的主要功能模块,并以国内典型的RP-3型航空煤油为例,实现了以航空燃料为热沉的热管理系统参数设计过程。  相似文献   

11.
于克杰  李艳  曹俊彬 《粘接》2011,(11):92-93
针对某军用飞机整体油箱在使用中的渗油故障,分析了油箱密封舱产生燃油泄漏的一般原因,给出了排除渗漏故障的工艺方法,解决了4号整体油箱的渗油问题。本方法为油箱密封舱泄漏问题的解决提供了参考。  相似文献   

12.
阿嵘  庞丽萍  杨东升  齐玢 《化工学报》2020,71(z1):315-321
先进的高速飞行器面临着气动加热与大功率电子设备发热的双重热负荷,使得机载热沉与能量需求呈指数上升趋势,进而导致发动机性能下降、耗油量增加,严重制约着飞行器的功能和性能提升。机载热管理系统的优化设计,旨在提升系统制冷和供电性能的同时减小发动机性能损失。以Mach数Ma=1~4.4的大热负载高速飞行器为背景,针对三种机载综合热管理系统,开展适应飞行任务的系统优化设计,实现燃油热沉、外涵道引气热沉、冲压空气引气、发动机引气与飞行任务的最优匹配。研究过程采用等效质量方法,将各系统质量、能耗、气源消耗等成本统一等效为燃油代偿损失,并作为目标函数,对多种工况进行优化设计。研究结果表明:在Ma≤2时,采用外涵道空气热沉模式更为合适,但随飞行速度的进一步提高,其制冷循环压比显著上升制冷效率降低,燃油代偿损失急剧上升;基于燃油热沉的综合热管理模式更适用于Ma=2~4.5的飞行任务,其制冷循环功耗和能耗在各飞行工况下性能表现较为稳定,燃油代偿损失仅因飞行速度增大而增大;与发动机引气相比,冲压空气引气更适合Mach数较高的飞行任务规划。因此,对于巡航Ma≤2的飞行器,搭载“外涵道引气热沉+发动机引气”的机载综合热管理系统,发动机性能损失更低;对于巡航Ma=2~4.5的飞行器,搭载“燃油热沉+可切换发动机引气/冲压空气引气”的机载综合热管理系统,发动机性能最优。  相似文献   

13.
J. Geng  X. Li  G. Sun  B. Yi 《Fuel Cells》2010,10(4):608-612
This paper presents a simple and reliable pumpless methanol feeding (PLMF) method for application in direct methanol fuel cell (DMFC) systems. The primary feature and advantage of the PLMF is as follows: it employs an approach that allows the cathode gas pressure to be connected with a fuel container for supplying the methanol fuel into the anode fuel loop, instead of using any feeding pump or other specially designed apparatuses. The PLMF has been used in a portable 25 W DMFC system and realised feeding methanol in real time for meeting the requirements of the system. The PLMF method not only is suitable for the DMFC system, but also can be used in other liquid‐feeding fuel cell systems.  相似文献   

14.
出于降低单车成本的需要,同时也为了满足环保法规和社会可持续发展的需要,需对原电泳槽内电泳漆进行置换,在进行电泳漆置换前,需要对其进行配套性试验和可行性评估分析,同时还需在实验室对混槽置换模拟试验进行验证,只有在验证合格的前提下,才能对现场电泳槽内电泳漆进行置换,针对此次电泳漆置换试验进行总结与分析以供同行分享和参考。  相似文献   

15.
A review of tomography systems suitable for industrial implementation and design considerations for tomographic sensors has allowed the design of an ERT sensor compatible with stringent process requirements. In conjunction with a data acquisition system, ITS P2000, this sensor was applied to processes considered typical of Active Pharmaceutical Ingredients (API) chemical development. Experimental results are described where variations in conductivity measurements were monitored in a stirred tank. The data were compared with spectroscopic on‐line monitoring and kinetic information. The results obtained demonstrate that this approach shows promise for on‐line control of mixing process performance and efficiency evaluation and optimisation of reactor geometries.  相似文献   

16.
李毅  袁永熠  廖中亮 《化工进展》2020,39(3):916-923
针对某型号高温甲醇燃料电池单电池模块,以实现精确控温、快速启动为目的进行了燃料电池热管理系统的设计、制造和测试。应用Matlab/Simulink平台开发了一种拟合简化方程的控制系统算法及其仿真计算平台,并对所设计的控制算法进行了仿真计算;同时对燃料电池内外传热介质循环回路及冷却系统换热器进行了重新设计与样件试制。完成了热管理系统单电池模块运行试验,将实测数据与仿真计算结果进行了对比分析。试验结果表明,所设计热管理系统成功将电池预热时间缩短了678s,稳定工况下冷却介质温度误差保持在±2℃以内,达到了预定的设计要求。样件试制及测试结果验证了热管理系统设计的可行性、准确性及实用性,为今后高温甲醇燃料电池热管理系统设计优化提供了理论和实际参考。  相似文献   

17.
Biodiesel fuel represents an interesting alternative as a clean and renewable substitute of fossil fuels. A typical biodiesel production process involves the use of a catalyst, which implies high energy consumptions for the separation of the catalyst and the by-products of the reaction, including those of undesirable side reactions (such as the saponification reaction). A recently proposed process involves the use of short-chain alcohols at supercritical conditions, avoiding the use of a catalyst and the occurrence of the saponification reaction. This process requires fewer pieces of equipment than the conventional one, but its high energy requirements and the need of special materials that support the reaction conditions makes the main product, biodiesel fuel, more expensive than petroleum diesel. In this work, a modification of the supercritical process for the production of biodiesel fuel is proposed. Two alternatives are proposed. The process involves the use of either reactive distillation or thermally coupled reactive distillation. Simulations have been carried out by using the Aspen One™ process simulator to demonstrate the feasibility of such alternatives to produce biodiesel with methanol at high pressure conditions. A design method for the thermally coupled system is also proposed. Both systems have been tested and the results indicate favorable energy performance when compared to the original scheme. Furthermore, the thermally coupled system shows lower energy consumptions than the reactive distillation column.  相似文献   

18.
A simulation model of a car driven by a gasoline based fuel cell system was generated with Matlab/SIMULINK. The model of the vehicle represents a common compact class passenger car equipped with an electric power train, fuel cell system and with and without an additional battery. For the fuel cell system two variants have been implemented, a PEMFC and a high temperature SOFC system. Both models consist of an on‐board gasoline reformer, stack and auxiliary components such as evaporator, catalytic burner, fuel pump, fans and control unit with additional FC‐type specific components such as air preheater or CO‐shifter. The simulation model allows the comparison of the two FC systems in different automotive traction concepts (fuel cell vehicle, hybrid car) varying all important parameters such as driving cycle or fuel cell nominal power. In this paper the simulation model is described and first simulation results are given.  相似文献   

19.
This work is based on the hybrid system emulator plant developed by the Thermochemical Power Group (TPG) of the University of Genoa. This rig is composed of a 100 kW microturbine coupled with high temperature fuel cell emulation devices. A real‐time model is used for components not physically present in the laboratory (solid oxide fuel cell (SOFC), reformer, anodic circuit, off‐gas burner, cathode blower). It is necessary to evaluate thermodynamic and electrochemical performance related to SOFC systems. Using an User Datagram Protocol (UDP) based connection with the control/acquisition software, it generates a hardware‐in‐the‐loop (HIL) facility for hybrid system emulation. Temperature, pressure, and mass flow rate at the recuperator outlet and machine rotational speed are measured in the plant and used as inputs for the model. The turbine outlet temperature (TOT) calculated by the model is fed into the machine control system and the turbine electric load is changed to match the model TOT values (effective plant/model coupling to avoid modifications on microturbine controller). Different tests were carried out to analyze hybrid system technology through the interaction between an experimental plant and a real‐time model. Double step and double ramp tests of current and fuel provided the system dynamic response.  相似文献   

20.
本文介绍了新型聚硫密封剂的特性、用途,使用方法及制备工艺和性能测试结果。  相似文献   

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