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41.
1前言认识压气机叶栅内部分离流动的结构和特性,对于揭示压气机内复杂的流动机制、改善叶栅气动性能、减少流动损失和提高压气机喘振裕度具有重要意义山。本文采用激光片光层加示踪粒子流场显示技术,观察和摄取了环形压气机叶栅在约十14”大攻角下的内部流动图像;采用七孔气 相似文献
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V. M. Astashinskii 《Journal of Applied Spectroscopy》2000,67(2):312-319
This article presents the results of experimental investigations of compression erosion plasma fluxes of a given composition
determined by the material of the internal electrode; the fluxes have been obtained for the first time in air at atmospheric
pressure. It is shown that a compression erosion plasma flux possesses marked absorption in the visible spectral region. The
basic thermodynamic parameters of these fluxes were determined with the use of a two-channel system of recording plasma radiation.
Reported at the International Conference on Plasma Physics and Plasma Technologies, Minsk, September 15–19, 1997.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 2, pp. 229–233, March–April, 2000. 相似文献
43.
三维FW-H方程与CAA数值模拟匹配技术研究 总被引:1,自引:0,他引:1
本文研究了三维FW-H方程与CAA数值模拟匹配技术。首先验证了适于亚音任意运动声源的Farassat时域公式和适于亚音匀速直线运动声源的Lockard频域公式,采用均匀流中单极子源声辐射问题对两类公式进行了校核。进一步,采用FW-H/CAA匹配技术对风扇/压气机前传声进行了预测。近声场基于轴对称三维CAA方法获得,远声场则基于近声场数据采用三维可穿透FW-H方程时域公式进行预测,并校核算例着重分析了不同积分面对远场声指向性的影响。本文研究证实了FW-H/CAA数值模拟匹配技术的可行性和解决工程实际问题的潜力。 相似文献
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The transient response analysis of the SLED based on the equivalent circuit is described. Then, a C-band SLED using TE0,1,15 mode cylindrical cavity with TE10-TE01 mode converter has been designed. According to the main RF parameters of the accelerator, the coupling coefficient is optimized to obtain the maximum multiplication factor. The key components of the pulse compressor include a 3 dB directional coupler, a TE10-TE01 mode converter,and a cylindrical cavity, which are simulated and optimized using 3D electromagnetic field simulation software. In addition, the function defining the relation between the coupling factor and aperture size is derived by a mathematical fitting method. 相似文献
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Pressure pulsations excited by a centrifugal turbomachinery such as compressor, fan or pump at the blade passing frequency may cause severe noise and vibrations in piping system. Therefore, the practical evaluation method of pressure pulsations is strongly recommended. In particular, the maximum pressure amplitude under the resonant conditions should be appropriately evaluated. In this study, a one-dimensional excitation source model for a compressor or pump is introduced based on the equation of motion, so as to incorporate the non-linear damping proportional to velocity squared in the total piping system including the compressor or pump. The damping characteristics of the compressor or pump are investigated by using the semi-empirical model. It is shown that the resistance coefficient of the compressor or pump depends on the Reynolds number that is defined using the equivalent velocity of the pulsating flow. The frequency response of the pressure amplitude and the pressure distribution in the piping system can be evaluated by introducing the equivalent resistance of the compressor or pump and that of piping system. In particular, the relation of the maximum pressure amplitude in piping system to the location of the excitation source under resonant conditions can be evaluated. Finally, the reduction of the pressure pulsations by use of an orifice plate is discussed in terms of the pulsation energy loss. 相似文献
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