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基于多体系统传递矩阵法的多管火箭定向器振动控制 总被引:1,自引:0,他引:1
应用多体系统传递矩阵法,建立了全新的多管火箭发射动力学控制模型,以二次型性能指标为成本函数, 设计了脉冲推力器为控制执行机构的振动主动控制律,并设计了多管火箭发射系统在燃气流冲击下定向器的振动主动控制系统,获得了最优脉冲控制力幅值和脉冲推力器工作次数. 应用设计的控制律数值仿真了某多管火箭定向器无控和受控状态下的振动响应,仿真结果表明该法可有效地降低定向器的振动.该方法易于工程实现,对控制多管火箭发射系统的振动、提高多管火箭射击的精度具有重要意义. 相似文献
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YANG Bin GUO Hao-ran GUI Xin-yang LIU Xin WANG Zhi-xin CHEN Xiao-long LIU Pei-jin 《光谱学与光谱分析》2018,38(6):1958-1962
针对固体火箭发动机恶劣环境下的高温燃烧测量问题,提出了利用辐射光谱法来开展固体火箭推进剂燃烧温度在线测量的方法,采用200~1 100 nm光纤光谱仪测量了高压实验燃烧器下固体火箭推进剂燃烧火焰辐射光谱,总结了其光谱特性,并基于普朗克定律和光谱拟合方法获得了相应的推进剂燃烧温度,这对固体火箭推进剂燃烧诊断与燃烧机理研究具有重要的参考价值。 相似文献
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M. M. Litvak J. A. Weiss G. F. Dionne 《International Journal of Infrared and Millimeter Waves》1980,1(4):561-579
The problem of detecting rocket plumes at thermospheric altitudes with satellite-borne submillimeter-wave radiometers is examined theoretically. To estimate the sizes of plume signatures contrasted against a 250-K earth background or in self-emission against the cold sky, a computer program has been developed to predict plume brightness temperatures and optical depths of rotational lines of plume molecular constituents (e.g., H2O) as a function of distance from the nozzle. The methods employed in the computations are described in general terms, and examples are presented to indicate that detectable H2O signatures extending to several thousand nozzle diameters should exist at plume altitudes above 250 km. 相似文献
67.
IntroductionThe problem of motion control for the mass center of ballistic rocket pertained typicallyto the boundary value problem for two points with the non-linear and multi-variables,namely,given the initial states of rocket,in order to satisfy the res… 相似文献
68.
Dmitry S. Kosyakov Nikolay V. Ul’yanovskii Sergey A. Pokryshkin Dmitry E. Lakhmanov Oleg A. Shpigun 《International journal of environmental analytical chemistry》2015,95(14):1321-1337
A method for the analytical extraction of mobile species of eightmain transformation products of 1,1-dimethylhydrazine (formaldehyde dimethylhydrazone, acetaldehyde dimethylhydrazone, 2-furaldehyde dimethylhydrazone, 1,1,4,4-tetramethyl-2-tetrazene, N,N-dimethylformamide, N-nitrosodimethylamine, 1-methyl-1H-1,2,4-triazole, and 1-formyl-2,2-dimethylhydrazine) from soils using subcritical acetonitrile at a pressure of 100 bar is proposed. The effects of temperature, number of extraction cycles, and the moisture content of soil samples on the recovery of analytes were studied. It was found that, for soils with high concentrations of lignin humic substances, efficient extraction can be attained with an addition of significant amounts of alkali to the soil (2.5 g/g). Under the optimum conditions, the recovery of analytes was higher than 70% at the extraction time no more than 30 min. A combination of the proposed sample preparation approach with analysis by gas chromatography–tandem mass spectrometry (GC-MS/MS) ensures the determination of the products of unsymmetrical dimethylhydrazine (UDMH) transformation in complex matrixes, such as soils with high concentrations of organic substance with detection limits from 1.8 to 15 µg kg–1 using the direct injection of the extract into the chromatography system. The error of determination at a confidential probability of 0.95 was not worse than 15% even for analyte concentrations close to lower limit of quantitation (LLOQ) values. The method developed is a significant improvement compared to the highly efficient methods previously reported in literature differing from them with simple sample preparation, rapidity, low consumption of reagents, the possibility of simultaneous determination of eight compounds and 1–2 orders of higher sensitivity. It was successfully used for the analysis of real samples of peaty soil from the place of impact of the first step of a carrier rocket. 相似文献
69.
Dmitry S. Kosyakov Ilya I. Pikovskoi Nikolay V. Ul’yanovskii Alexander Yu. Kozhevnikov 《International journal of environmental analytical chemistry》2017,97(4):313-329
A promising alternative to ion-chromatographic methods currently used for the direct determination of hydrazines is provided by hydrophilic interaction liquid chromatography (HILIC). In this work, we propose a method for the simultaneous determination of hydrazine, methylhydrazine and 1,1-dimethylhydrazine in natural waters and soils based on a combination of chromatographic separation on a zwitterionic sulfobetaine stationary phase (Nucleodur HILIC) in the HILIC mode with amperometric detection.Effects of different factors on the retention of analytes were studied and the optimum conditions of analysis were found. We recommend a mixture of acetonitrile with an aqueous phosphate buffer solution of pH 2.5 (78:22 v/v) with an ionic strength of 20 mM as a mobile phase. Detection in the direct current mode was performed at a working electrode potential of 1.1 V.The advantages of the method are the high efficiency of separation, rapidity, high sensitivity and a wide dynamic range of analyte concentrations, covering four orders of magnitude. The attained LOD values for analytes lie in the range 0.07–0.13 μg L–1, which is two orders of magnitude lower than those in currently used methods of ion chromatography with electrochemical and mass spectrometric detection.The method was validated on samples of natural waters of different origin using the added–found technique. It was found that the error of analysis did not exceed 10% for river and ground waters and increased to 20–30% for peat bog surface waters.The possibility of application of the developed method to the analysis of soils was shown on samples of peat bog soils selected at places of impact of the first steps of carrier rockets and polluted by rocket fuel based on 1,1-dimethylhydrazine. 相似文献
70.
本文提出一种线性函数斜率的确定方法并证明用其近似代替网格内流动变量的初始分布,MUSCL格式具有二阶精度。引入单调性限制条件和一定的耗散机制后,该方法适合于Euler坐标系下的计算。本文在处理间断时,用激波关系式代替特征线方程,解决了特征线法在全流场计算中的应用问题。最后,本文给出Emery问题和一个火箭喷流问题的计算结果。 相似文献