空间熔盐堆运行过程中,反应性控制起到十分重要的作用,目前陆地上常采用的主动反应性控制方式存在出现故障的概率等问题。空间熔盐堆需要一种非能动反应性控制方式,在无需外源及人为操控情况下,对反应性实施自动控制,降低事故发生风险...空间熔盐堆运行过程中,反应性控制起到十分重要的作用,目前陆地上常采用的主动反应性控制方式存在出现故障的概率等问题。空间熔盐堆需要一种非能动反应性控制方式,在无需外源及人为操控情况下,对反应性实施自动控制,降低事故发生风险。本文针对热管式液态燃料空间熔盐堆,利用液态燃料的热胀冷缩机制,当堆芯处在正常运行工况下温度发生变化时,提出并设计一种液态燃料移出移入非能动反应性控制系统(Liquid Fuel in/out Transfer in a Passive Reactivity Control System,LFT-PRCS),并对含有该系统的堆芯进行在正常运行工况下物理特性分析,以及该系统结构参数与反应性补偿能力分析。结果表明:正常运行工况下,含有LFT-PRCS的堆芯具有更负的反应性,且堆芯物理特性未发生明显变化;LFT-PRCS中毛细管道较佳结构参数为:高度为10 cm、内层半径为0.2 cm、外层半径为0.4 cm;LFT-PRCS在寿期初、寿期末温度发生2 K波动时,可向堆芯引入约20 pcm的反应性。上述结果表明,LFT-PRCS可提高堆芯固有安全性,一定程度上补偿燃耗造成的反应性损失。展开更多
There are two kinds of internationally recognized approaches in terms of lightweight design.One is based on fatigue accumulated damage theory to achieve better reliability by optimal structural design; another is to u...There are two kinds of internationally recognized approaches in terms of lightweight design.One is based on fatigue accumulated damage theory to achieve better reliability by optimal structural design; another is to use high performance lightweight materials.The former method takes very few considerations on the structural strengthening effects caused by the massive small loads in service.In order to ensure safety,the design is usually conservative,but the strength potential of the component is not fully exerted.In the latter method,cost is the biggest obstacle to lightweight materials in automotive applications.For the purpose of light weighting design on a fuel cell vehicle,the new design method is applied on drive shafts.The method is based on the low amplitude load strengthening characteristics of the material,and allows the stress,corresponding to test load,to enter into the strengthened range of the material.Under this condition,the light weighting design should assure that the reliability of the shaft is not impaired,even maximizes the strength potential of machine part in order to achieve the weight reduction and eventually to reduce the cost.At last,the feasibility of the design is verified by means of strength analysis and modal analysis based on the CAD model of light weighted shaft.The design applies to the load case of half shaft in independent axle,also provides technological reference for the structural lightweight design of vehicles and other machineries.展开更多
文摘空间熔盐堆运行过程中,反应性控制起到十分重要的作用,目前陆地上常采用的主动反应性控制方式存在出现故障的概率等问题。空间熔盐堆需要一种非能动反应性控制方式,在无需外源及人为操控情况下,对反应性实施自动控制,降低事故发生风险。本文针对热管式液态燃料空间熔盐堆,利用液态燃料的热胀冷缩机制,当堆芯处在正常运行工况下温度发生变化时,提出并设计一种液态燃料移出移入非能动反应性控制系统(Liquid Fuel in/out Transfer in a Passive Reactivity Control System,LFT-PRCS),并对含有该系统的堆芯进行在正常运行工况下物理特性分析,以及该系统结构参数与反应性补偿能力分析。结果表明:正常运行工况下,含有LFT-PRCS的堆芯具有更负的反应性,且堆芯物理特性未发生明显变化;LFT-PRCS中毛细管道较佳结构参数为:高度为10 cm、内层半径为0.2 cm、外层半径为0.4 cm;LFT-PRCS在寿期初、寿期末温度发生2 K波动时,可向堆芯引入约20 pcm的反应性。上述结果表明,LFT-PRCS可提高堆芯固有安全性,一定程度上补偿燃耗造成的反应性损失。
基金supported by National Natural Science Foundation of China (Grant No. 50875173)Shanghai Municipal Education Commission Key Foundation of China (Grant No. 09ZZ157)Shanghai Leading Academic Discipline Project of China (Grant No. J50503)
文摘There are two kinds of internationally recognized approaches in terms of lightweight design.One is based on fatigue accumulated damage theory to achieve better reliability by optimal structural design; another is to use high performance lightweight materials.The former method takes very few considerations on the structural strengthening effects caused by the massive small loads in service.In order to ensure safety,the design is usually conservative,but the strength potential of the component is not fully exerted.In the latter method,cost is the biggest obstacle to lightweight materials in automotive applications.For the purpose of light weighting design on a fuel cell vehicle,the new design method is applied on drive shafts.The method is based on the low amplitude load strengthening characteristics of the material,and allows the stress,corresponding to test load,to enter into the strengthened range of the material.Under this condition,the light weighting design should assure that the reliability of the shaft is not impaired,even maximizes the strength potential of machine part in order to achieve the weight reduction and eventually to reduce the cost.At last,the feasibility of the design is verified by means of strength analysis and modal analysis based on the CAD model of light weighted shaft.The design applies to the load case of half shaft in independent axle,also provides technological reference for the structural lightweight design of vehicles and other machineries.
