2020/8/8 11:01:28 XI Chang, CAI Zhiming, YUAN Jun 21true 2020/8/8 11:01:28 MA Jianfei, YAN Bing, LIN Chunsheng, CHEN Hao 20true 2020/8/8 11:01:29 SU Shipeng, CAO Xiaoqun, ZHANG Daquan, WEI Zhiyuan 19true 6 cathode has the advantage of high electron emission current density, and has been widely used in electric propulsion, high emission density electron gun and other products. In order to analyze the poisoning characteristics of the LaB₆ hollow cathode and identify its failure mode, the performance change features and reasons of LaB₆ hollow cathode exposed to atmosphere were studied. The results show that the LaB₆ hollow cathode adsorbs a great deal of poisonous gas on the surface of the emitter during exposure to the atmosphere, and while the work function from the emitter surface increases, the emitter appears short-term poisoning phenomenon. The discharge voltage and hollow cathode plate temperature are increased, and the discharge voltage and cathode top temperature are restored to the initial state after short-term operation. However, if the poisoning phenomenon of LaB₆ hollow cathode is serious, the oxide generated on the surface can not be removed by heating and ion bombardment. Therefore, the emitter state of hollow cathode can be indirectly characterized by monitoring the change of cathode temperature and anode voltage during the test.]]> 2020/10/21 15:55:40 YANG Wei, ZHANG Tianping, LONG Jianfei, GUO Ning, LIU Mingzheng, GU Zengjie 18true 2020/10/21 15:55:40 CHEN Chen, XU Wenqin, ZHANG Mingyang 17true 2020/10/21 15:55:40 DUI Hongyan, BAI Guanghan, ZHANG Yunan, ZHANG Xiaoke, WANG Chuang 16true 2020/10/21 15:55:40 HU Jie, ZHU Yixian, SHAN Yao 15true 2020/10/21 15:55:40 JI Huiming, YU Minjian, QIAO Xinhang, YANG Haiyan, ZHANG Shuaiwen 14true 2020/10/21 15:55:40 LI Zhe, HAN Yiliang, LI Yu, ZHU Shuaishuai, YANG Xiaoyuan 13true 2020/7/6 0:00:00 ZHOU Xiaosong, ZHANG Yanbing, MEI Zhiyuan 12true 2020/7/6 10:23:21 BIAN Liping, XING Suli, YIN Changping 11true 2020/7/6 10:23:21 ZHANG Lei, SHENG Li 10true 4 expander cycle throttling liquid rocket engine are rare and its recognition of it is not distinct, especially at the system level. Based on the whole engine system, the theoretical method was adopted to investigate the work capacity of CH₄ and the feasibility of throttling schemes. The single-turbine and double-turbine throttling schemes were given, and the detailed comparison between them was analyzed. The results reveal that CH₄ work capacity decreases at first and then increases with the decrease of chamber pressure. And the proposed throttling schemes are feasible. Moreover, compared with the single-turbine scheme, the oxidizer and fuel mass flows can be adjusted respectively for double-turbine scheme and the mixture ratio can keep constant better. Meanwhile, the work capacity of CH₄ for double-turbine scheme is much higher, the powers of the oxygen and fuel turbines vary in a narrow range, and the turbines work in a more relaxed environment. Therefore, considering the system reliability, the double-turbine scheme is advantageous to a certain extent.]]> 2020/7/6 10:23:21 CUI Peng, LI Qinglian, CHENG Peng, ZHANG Beichen 9true 2022/4/1 11:52:58 ZHANG Pu, XUE Huifeng, GAO Shan, ZUO Xuan 8true 2022/4/1 11:52:58 XING Bingnan, DU Zhonghua, DU Chengxin 7true 2022/4/1 0:00:00 LIU Zhuoqun, ZHANG Xiang, HUANG Yiyong, CHEN Xiaoqian, ZHAO Yong 6true 2022/4/1 11:52:58 WU Wanyang, ZHONG Jingjun 5true 2022/4/1 11:52:58 ZHOU Lei, YANG Kun, NIE Tao, WU Xin, LIU Nan 4true 2022/4/1 11:52:58 GUO Chun, GUO Shangsheng, QIAN Jianping, GU Wenbin 3true 2022/4/1 0:00:00 LIANG Yundong, HE Lin, XU Rongwu, CHEN Zongbin 2true xr automatically vanishes on the inner and outer surface of cylindrical tubes when an appropriate warping shape function instead of the shear correction coefficient is chosen. And it can provide analytical solutions with sufficient accuracy for the bending problems of cylindrical tubes with different length-diameter ratios and thickness-diameter ratios. When the stiffness coefficient approaches zero, the deflection curve of cylindrical tube embedded in Winkler elastic foundation approaches the deflection curve of cylindrical tube placed in free space, which verifies the accuracy of the present method. Different from the Euler-Bernoulli beam theory, the normal stress over the cross-section is no longer linear with the abscissa from the neutral surface in this method, and it is especially obvious when the length-diameter ratio is small and the thickness-diameter ratio is large.The shear stress τ_xz decreases when the distance from the neutral surface becomes large, approaching zero at the top and bottom positions, and the maximum shear stress occurs at the neutral surface which is close to the inner surface.]]> 2022/4/1 11:52:58 MA Weili, SHEN Liulei, SONG Dianyi, LI Xianfang 1true