车载复合材料高压储氢气瓶快速充装温升控制数值模拟研究

针对碳纤维增强复合材料气瓶的快速充氢过程,建立了70 MPa储氢气瓶快速充装数值模型,研究了不同充装参数对瓶内氢气温升的影响规律,探讨了温升的控制策略,提出了温升的控制方法.结果表明:气瓶快充温升主要由充装时间、气瓶初始压力以及初始温度决定,初始充装压力增大对降低温升有显著影响;初始充装压力和初始温度与温升近似呈线性关...     

氢气快充温升控制装置数值设计

高压氢气从储氢罐到氢气瓶的加注过程中存在一定的温升．从安全角度出发,本文建立了高压氢气快充温升控制设计模型,基于模型对氢气快充温升控制装置进行了数值分析,并提出了氢气快充温升控制装置的数值设计方法。研究结果可以为加氢站等对于初始温度有要求场合的设计提供参考。     

天然气气瓶快充过程温升数值模拟研究

通过对天然气气瓶快充过程温升机理的分析,建立了天然气气瓶快充温升数值计算模型.应用模型对天然气气瓶在不同充装参数(包括起始温度、初始压力与充装速率等)下的温升进行了预测.结果表明:气瓶初始压力对快充温升的影响呈线性减小关系;温升近似与初始温度呈线性增长关系;随着气瓶充装速率的提高,气瓶内最大温升逐渐增加,但呈非线性增加...     

高压储氢容器失稳分析与研制

借助有限元方法对高压储氢容器进行分析计算,采用ANSYS软件对碳纤维复合材料高压储氢容器内衬的各阶模态失稳进行研究,结合设定的预应力和安全余量,采用了4mm厚的内衬厚度。通过70MPa高压储氢容器快速充放氢系统进行氢环境的疲劳试验,同时进行耐压试验、耐冲击试验和爆破试验,且都得到了安全验证。     

轻质高压储氢容器

氢的储运是氢能发展的关键技术之一。轻质高压储氢是一种切实可行的氢能储运方法。结合纤维缠绕气瓶和高压储氢容器的国内外最新研究进展,介绍了轻质高压储氢容器的结构、设计方法和有待深入研究的若干问题。     

复合材料气瓶高低温条件下的疲劳及爆破性能研究

本文缠绕成型130 L复合材料气瓶,进行了充放气疲劳及水压爆破试验,并且采用声发射的检测方法对充放气疲劳试验过程进行了监控。试验结果表明:充放气疲劳过程中复合材料气瓶除了承受内压载荷作用,同时还承受由于充放气导致的温度变化产生的热应力,内压以及热应力对气瓶的损伤较大,会导致气瓶疲劳后的爆破压强下降。     

不同水容积的车载储氢气瓶快充温升研究

高压气态储氢是氢能汽车的主流技术解决方案,氢能汽车加氢操作时间应与燃油车加油操作时间相近.但快充过程伴有较高温升,这将诱发环氧树脂剥离、碳纤维失效及气瓶欠充装等问题,故应准确预测温升并给定可靠的加注策略.因此需要关注不同水容积的储氢气瓶,揭示氢气、复合层压板的温升演化,并给定高精度、宽适用范围的温升预测公式.     

复合材料高压气瓶用玻璃纤维开发研究

简要介绍了复合材料高压气瓶的发展状况、分类、特点以及相关标准。详细总结了复合材料高压气瓶用玻璃纤维的质量要求,研究开发了一种性能优异、适合于缠绕复合材料高压容器的玻璃纤维产品,并介绍了这种玻璃纤维产品的主要性能指标。     

高压氢气储运设施泄漏喷射火过程预测模型及其验证

近年氢能已迅速成为能源领域“新宠”,正在迎来快速发展的战略机遇期,但氢安全问题仍然是制约其发展的关键,尤以高压氢气储运设施泄漏后引发喷射火灾害较为突出。为了探究高压氢气泄漏过程并对其引发喷射火灾特性参数变化进行评估,本文采用理论分析和实例验证相结合的方法对两起高压氢气泄漏实验案例（90 MPa氢气瓶和6 MPa氢气管道）进行了研究。结果表明：通过模型精度检验,Abel-Nobel气体状态方程适用于当前常用的多种高压氢气储运设施泄漏过程的描述。基于Abel-Nobel气体状态方程、火焰尺寸模型、辐射分数模型和热辐射模型构建的高压氢气泄漏喷射火过程预测模型对实验案例中的泄漏出口气体质量流量、氢喷射火焰长度和辐射热场等的模拟计算结果与实验测量数据基本一致,验证了模型有效性及所含假设合理性。另外在计算中还需要结合实际情况充分考虑高压氢气储运设施发生泄漏时产生的能量损失以及等温流动过程,从而对模型预测精度进行修正。上述结论对于工程实际、氢能安全利用以及灾害预防等具有重要现实意义。     

大型碳纤维复合材料气瓶在压缩天然气储运领域中的研制与应用进展

采用碳纤维缠绕成型技术制造的大型压缩天然气(CNG)气瓶,具有质量轻、强度高、疲劳强度好,耐腐蚀等特点,可以满足海洋油田天然气开发及天然气的陆上储运等领域的应用需求。本文综述了国际上大型碳纤维复合材料CNG气瓶的研制及应用现状,结合国内天然气开发及储运和国产碳纤维复合材料应用的现实,提出了研制大型CNG复合材料气瓶应突破的关键技术、标准规范以及成型装备等。     

Activated carbon fibres and composites on its base for high performance hydrogen storage system

To obtain high hydrogen sorption capacity and reduce the time of the cycle (adsorption/desorption) in the gas storage system a new composite material (metal hydride particles on the activated carbon fibre matrix) was suggested. Different adsorbent materials such as activated carbon fibre “Busofit”, granular activated carbon and new composite sorbent (metal hydride La_0.5Ni₅Ce_0.5 particles on the activated carbon fibre “Busofit”) were tested. Effect of the carbon sorbent nature and metal hydride content is important to choose the optimal sorbent bed.In this paper, a thermally regulated storage system for hydrogen was numerically analyzed and experimentally validated. A two-dimensional transient model was used to analyze the influence of the thermal control on the operating characteristics of the flat sectional vessel. The evolution of the temperature, pressure and volumetric density of hydrogen inside the vessel during the charging/discharging is discussed. It was shown that heat pipe based thermal control of the process increase the efficiency of the hydrogen storage. Such vessels are interesting to be applied in fuel cells used for vehicle or dual-fuel engine car (hydrogen/gasoline, hydrogen/methane).     

壳管式潜热蓄能系统换热特性

针对目前石蜡潜热蓄能系统效率低下的特点,构建了石蜡/膨胀石墨混合相变材料的潜热蓄能系统,研究了其蓄/放热特性,并与纯石蜡相变材料系统进行了对比分析,讨论了不同换热流体流量下的蓄/放热过程的时间周期。用焓法处理相变区域,对该潜热蓄能系统的整体蓄热过程进行数值模拟。研究结果表明,对于石蜡／膨胀石墨复合相变材料,其导热性能较纯石蜡有很大提高,但由于添加了膨胀石墨而减弱了蓄热中石蜡的对流换热。流量提高对蓄/放热速率有明显的改善。焓法模型能全面反映蓄能系统的换热与流动特性,数值计算的结果与实验数据吻合较好。     

Thermodynamic Analysis of Single Reservoir Filling Process of Hydrogen Vehicle

The accurate modeling of the fast-fill dynamics occurring in hydrogen fueled vehicle storage cylinders is a complex process, and to date those dynamics have not been thoroughly studied. In this paper, based on the first and second laws of thermodynamics, conservation of mass and real gas assumptions, a numerical method has been developed to study the fast filling process of the hydrogen vehicle’s cylinder. Thermodynamic properties' table has been employed for the case of the real gas model. The model has been applied for a single reservoir tank. The results indicate that there is a temperature rise on the order of 100 K or more during the charging process. The results also indicate that ambient temperature has a strong effect on the filling process and final hydrogen cylinder conditions.     

平板微热管阵列-泡沫铜复合结构相变蓄热装置蓄放热特性

相变蓄热技术是节能减排的一个重要手段,在太阳能利用、余热回收和电力削峰填谷等领域发挥重要的作用。设计了以平板微热管阵列-泡沫铜复合结构为基础,多孔扁管为载热流体通路,水为载热介质,石蜡为相变材料的热管式蓄热装置。通过实验研究了蓄放热过程中装置内部石蜡的温度分布情况,不同载热流体温度和流量下的蓄放热功率变化,以及装置蓄放热效率等特性。实验结果表明,平板微热管阵列-泡沫铜复合结构可以使箱体内石蜡温度分布更加均匀;增加载热流体和相变材料的温差以及增大流量都可以提高蓄放热功率。实验条件下,该装置的最大蓄热功率为1.24 kW,最大放热功率为1.43 kW。装置蓄热效率为92%,放热效率为94%,总效率为87.4%。     

六水硝酸镁相变储热复合材料改性制备及储/放热性能研究

水合盐相变材料因具有较高的相变焓和较低的成本在中低温储热领域有着广泛的应用前景,但其在储放热过程中通常存在过冷度大和热循环稳定性差的问题。以六水硝酸镁为主要研究对象开展相变储热复合材料的改性制备及相变储热装置的研制,采用熔融共混法制备了以二水硫酸钙为成核剂的六水硝酸镁相变储热复合材料,利用差示扫描量热仪及步冷曲线法测试了相变储热复合材料的热物性和循环热稳定性。在此基础上设计并构建了储热量为152 kWh的相变储热装置和相变储热系统,并对其储/放热性能进行了测试。结果表明：添加了2%（质量）二水硫酸钙的相变储热复合材料具有较好的循环热稳定性,且在经过50次熔化-凝固循环后其过冷度一直保持在0.5℃内,相变温度保持在87℃左右,相变焓保持在150 kJ/kg以上;相变储热装置可实现高达27 kW的平均储热功率,在保证放热过程中出水温度不低于56℃的情况下,可实现8 kW的平均放热功率和92.3%的储-放热效率,可满足建筑采暖及日常生活热水需求。     

湿活性炭储天然气方法

Storing natural gas in wet active carbon is a recently proposed method. The research progress shows that this method considerably decreases the storage pressure while maintaining the storage capacity equal to or even higher than compressed natural gas （CNG）. There is no requirement of pre-sifting any component out of natural gas for the storage, and the thermal effect on fast charging/discharging has almost no effect on the storage capacity. The charging and discharging processes are reversible and show good dynamic behavior. Although the storage temperature is a little lower than the ambient, the new method seems technically and costly more competitive than the available methods.     

氢能供应链成本分析及建议

氢能具有能量密度高、环保清洁可再生的优势,已经成为未来能源发展的重要方向,被视为实现碳减排的必由之路。但目前氢能发展的核心问题是用氢成本过高,与电动车和传统燃油车相比没有经济优势。本文从制氢-运氢-加氢的产业链角度分析,发现电解水制氢成本远远高于化石能源制氢,且氢气的成本主要在运氢和加氢环节被抬升。文中指出：究其原因,主要由于氢气储存不易,在现有的长管拖车运输条件下,每次运输氢气量少,效率不高;同时由于燃料电池汽车数量少,每日加注量不足,叠合加氢站关键设备不能国产化,固定资产投资高导致折旧成本高,增加了氢气成本。针对这一问题,文中给出了具体降低成本建议,包括增加运氢压力以增加单次氢气运载量;加快科技攻关,关键设备国有化;突破政策限制,实现站内制氢;优化加氢站工艺,减少日常运营成本等。     

船用蒸汽蓄热器非平衡热力过程

船用蒸汽蓄热器作为舰船上弹射装置的重要组成部分,具有充、放汽时间短,短时间内蒸汽消耗量大等特点,其运行特性直接关系到弹射装置能否安全、稳定运行。建立了船用蒸汽蓄热器实验系统,以过热蒸汽作为充汽汽源,进行不同工况下的充汽、放汽及连续充放汽实验。实验结果表明：蓄热器充汽(放汽)过程中,其压力呈现先急剧上升(下降)后随充汽(放汽)阀门关闭下降(上升),最终趋于稳定的强烈的非平衡热力过程;由非平衡热力过程导致的压降比随单位时间内充入蓄热器能量的提升而加大;蓄热器内温度变化滞后于压力变化,水温变化滞后于汽温变化。蓄热器非平衡热力过程研究可为蒸汽弹射系统的安全运行提供一定的技术支撑。     

Hydrogen generation from noncatalytic hydrothermolysis of ammonia borane for vehicle applications

Ammonia borane (AB) is a promising hydrogen storage material as it contains 19.6 wt % hydrogen. In this article, our recently developed hydrothermolysis approach to release hydrogen is studied over a wide range of AB concentrations (6–88 wt %), at pressure 14.7 and 200 psia, and temperature 85–135°C. It is shown that with increasing AB concentration up to 77 wt %, the H₂ yield increases, and that the role of thermolysis, when compared with hydrolysis, increases. The maximum hydrogen storage capacity, obtained at 77 wt % AB and T_reactor ～ 85°C along with rapid kinetics, was 11.6 and 14.3 wt % at pressure 14.7 and 200 psia, respectively. To our knowledge, on a material basis, the AB hydrothermolysis process is the first one to provide such high hydrogen yield values at near PEM fuel cell operating temperatures without use of catalyst, and thus is promising for use in fuel cell‐based vehicle applications. © 2010 American Institute of Chemical Engineers AIChE J, 2011     

20 V stack of aqueous supercapacitors with carbon (−), titanium bipolar plates and CNT‐polypyrrole composite (+)

A 20 V stack of 19 supercapacitors was fabricated from titanium bipolar plates (150 × 150 × 0.1 mm³) coated on each side with carbon nanotubes and polypyrrole composite (+) and pigment carbon black (?), and microporous polymeric separators containing aqueous KCl. Internal sealing of each cell in the stack was achieved by placing a silicone rubber washer between neighboring bipolar plates. The stack was tested by high voltage cyclic voltammetry, galvanostatic charging and discharging, and electrochemical impedance spectroscopy. It approached 25 kW/kg in maximum specific power and 3.64 Wh/kg in specific energy. Performance of the stack through intermittent charging‐discharging tests in a storage period of 10 months (still ongoing) remained fairly stable. For example, it exhibited almost zero decay in capacitance after 1000 continuous galvanostatic charging‐discharging cycles in the first month of storage (10 V), and less than 6% loss in the seventh month (19 V). © 2011 American Institute of Chemical Engineers AIChE J, 2012