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I. E. Mikhailov Yu. V. Polikarpov A. K. Fink 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1992,26(11):724-727
1. | The installation of a conical transitional segment between a tower (shaft)-type water intake-outlet and penstock affects a significant reduction in head loss in the pump mode, but has virtually no effect on the magnitude of the latter in the pump mode. |
2. | The existence of a conical transitional element in the pump mode appreciably lowers the discharge velocities of the flow and increases the effective height of the water-passing openings by 1.5–1.7 times when the height of the intake openings h0.5dp. |
3. | The head losses in the intake-outlet decrease in the pump mode of operation with increasing degree of expansion of the transitional diffusor segment. |
5.
V. I. Koptev Yu. M. Gorshkov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1986,20(7):411-416
Conclusion The proposed method of detecting local defects in a cutoff curtain has a large radius of investigation and allows testing a 30-m-long section of the curtain during one experiment.Each experiment takes about 4 h. The area of use is limited to an evaluation of the quality of grout curtains constructed below the groundwater level. The method is intended for use together with other existing methods for increasing the details of checking grout curtains.In addition to a qualitative solution of the quality control problem (detection of local defects in the grout curtain), the method makes it possible to obtain a quantitative evaluation of the achieved effect based on solving the problem of the relation between the measured parameter
and effect of grouting
obtained for a homogeneous (porous) medium.The use of the described geophysical method of checking the quality of grout curtains makes it possible to increase the reliability of their work and to promptly introduce necessary changes into the grouting technology.Translated from Gidrotekhnickeskoe Stroitel'stvo, No. 7, pp. 23–27, July, 1986. 相似文献
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这次会议讨论的是一个很重要的题目──国企转型与企业文化构建。我们现在对企业文化的认识,如果同10年前相比,可以说是跨越了一个世纪。当时感觉企业文化是个新鲜东西,并不知道它有多大用途,好像很时髦,多数人对它的认识还是狭窄的、浮面的。10年后的今天,经过理论界的探索研究,特别是经过企业界的创新实践,使得我们对企业文化的认识有了很大的发展。中外企业文化杂志社利用庆祝创刊10周年的机会,组织大家共同研讨国企转型与企业文化构建,这个题目选得非常好。当前,企业文化在中国的需求,很重要的一点就是与国企转型联系在了一起。企业文化… 相似文献
7.
结合国家标准GB 50057-2010《建筑物防雷设计规范》和BS规范BS EN 62305-2006《Protection against lightning》,介绍了两本规范中建筑物防雷装置做法,简述了两种规范中有关建筑物外部防雷(接闪器、引下线、接地装置)、内部防雷以及防雷击电磁脉冲的有关规范条文规定和比较。 相似文献
8.
Yu. I. Frishter O. A. Kogodovskii 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1995,29(12):694-706
1. | When constructing earth dams the inclusion of foreign members in the form of reinforced-concrete galleries, shafts, etc., in the body of the structure is impermissible. It is also desirable to eliminate the construction of a grouting gallery under the dam. The foundation should be grouted either before or after constructing the dam. |
2. | Installation of monitoring and measuring equipment for observations during operation must be done after completing construction of the dam. Installation of MME during construction leads to its complete disturbance, holds up the rate of filling, and affects the quality of the works. |
9.
Viewed as sinews and muscles of fluid motion,coherent vortical structures with their interactions are key to understanding the flow dynamics.Based upon this observation,we explore the possibility of efficient flow control by directly manipulating vortices numerically inside the flow field based on the vortex definition and identification system of Liutex.The objective is twofold:(1)to study the vortex dynamics,for example,by observing the response of the flow to strengthening or weakening of certain vortices,and(2)to obtain efficient vortex-based control strategies which might lead us to practical applications.In the present numerical study,the manipulating of vortices is achieved by introducing additional source(force)terms to the Navier-Stokes equations,which hereafter will be collectively called Liutex force field model.Methodologies including controlling the rotation strength and centripetal force of particular vortices are detailed in a flow past a cylinder with different control purposes at Reynolds number of 200.Further examples are provided with a cavitating flow around two-dimensional Clark-Y hydrofoil,with particular interests on cavitation suppression.It is illustrated particular vortex with cavitation encircled could be effectively suppressed. 相似文献
10.
V. N. Shchedrin Yu. M. Kosichenko 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2011,45(4):264-269
A safety declaration is a fundamental document assuring the safety of water-development works, their correspondence to safety criteria, the design, and active technical regulations and rules. 相似文献