摘要
在进行SHPB系统高温实验时,波导杆常常与试件被同时加温,从而在波导杆中产生温度梯度。为了消除波导杆中温度梯度的影响,有研究人员利用传热学原理来对测量波形进行修正。本文利用一套自动组装装置,实验前对试件加热并自动保温,波导杆则置于加热炉外,实验时进行瞬态组装,由此避免了导杆温度梯度对波形的影响。本文介绍了自动组装原理和过程,比较了在200℃时导杆和试件同时加热,与采用自动组装所产生的透射波形的差异。同时应用ABQUS进行了接触热传导分析,比较了“冷接触时间”在40ms～500ms时试件上的温度分布,计算结果表明:自动组装条件下“冷接触时间”在400ms以内,试件温度不均匀可控制在10%以内。
In high temperature experiments of SHPB, the heater which is used to heat the specimen usually heats up the bars and causes non-uniform temperature field in the bar. In order to filter the effect of temperature gradient in the bars on measured results, some researchers took the measure of correcting the measured waves by use of the theory of heat conduction. In this paper, a method of assembling simultaneously the heated specimen and the unheated bars was discussed. By using this method, the heat in the high temperature specimen hardly affects on the temperature of the bars before the shocks end and therefore on the measured results. The assembling was automatically carried out by an auto-assembling apparatus and its principle was introduced. Moreover, the transmitted waves obtained by using the auto-assembling technique were compared with those by using the method of simultaneously heating the bars and the specimen at 200°C. Also ABQUS program was used to analyze contact thermal conductance in the specimen. The calculated temperature distributions in the specimen with 'cold-contact time' from 40ms to 500ms were compared, and the results demonstrate that the non-uniformity of temperature distributions in the specimen can be controlled under 10% with \{'cold-contact time'\} from 40ms to 400ms.
出处
《实验力学》
CSCD
北大核心
2005年第2期281-284,共4页
Journal of Experimental Mechanics
基金
国家自然科学基金(No.10232040)
中物院项目基金(2002-4210501-4-03)资助项目
