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Quenching with gases rather than oil or other liquid media has the advantages of reducing the risks concerning health and environment, while simultaneously homogenizing the quenching results and minimizing distortion due to a wide range of possible process parameter variations and the pure convective heat transfer. In this contribution, a coupled solution for increasing homogenization of quenching results within high pressure gas quenching will be presented. In the first stage, an experimental test facility was set up for flow investigations and in the second stage a numerical simulation model was generated. The numerical and experimental results of the flow through the chamber were compared for several boundary conditions. Finally, after complete verification of the simulation, the model may be used to assist in parameter variation for optimization of homogeneous high pressure gas quenching. 相似文献
105.
This paper shows how the theory of nonlinear adaptive observers can be effectively used in the design of internal models for nonlinear output regulation. The theory substantially enhances the existing results in the context of adaptive output regulation, by allowing for not necessarily stable zero dynamics of the controlled plant and by weakening the standard assumption of having the steady-state control input generated by a linear system. 相似文献
106.
自治Agents的面向服务的协商模型 总被引:3,自引:0,他引:3
提出了一个基于自治Agents的面向服务的协商模型。模型主要包括两大模块:首先定义了一系列的战略和战术过程,使得Agents可以产生初始建议,评价对方的建议,以及在此基础上做出反建议;其次,定义了两个层次的Agent通信机制。二者相辅相成,实现了Agents间合作的动态形成和随机协调,使得Agents可以承担因环境的不确定性而需动态协作的复杂任务。 相似文献
107.
Tan Guang-ming Wang Zhen-zhong Wuhan University of Hydraulic Electric Engineering Wuhan P.R.China 《水动力学研究与进展(B辑)》1992,(1)
It is mentioned in this paper that the adjustment of flow structure occurs when themain-flow swings.The changes of turbulence structure and flow energy loss in the indoor rivermodel are measured.The experimental data are presented for the first time for the further studyof complicated river flow structure. 相似文献
108.
In this paper, we employ a nonlinear adaptive mechanism to globally stabilize nth-order reactions. 相似文献
109.
H.Honda T.Fukuda Institute of Advanced Material Study Kyushyu University Kasuga Fukuoka Japan 《热科学学报(英文版)》1992,1(2):123-129
A theoretical study has been made to optimize the fin geometry of a horizontal finned tube which is to be usedfor condensers that handle the vapor load of a liquid phase change cooling module.Systematic numerical calcu-lations of the vapor to coolant heat transfer have been performed for parametric values of fin height,fin spacing,vertical bundle depth and tubeside heat transfer coefficient.Three dielectric fluids (R-113,FC-72,and FC-87)at atmospheric pressure were selected as the working fluids.For a single tube with optimized fin geometry,theaverage heat flux increased in the order of FC-87,R-113 and FC-72.Both the optimum fin height and optimumfin spacing increased with increasing vertical bundle depth. 相似文献
110.
Flooding phenomenon limits the stability and the flow of a liquid film falling along the walls of a channel in which a gas is flowing upwards.As known, the entrainment effect can completely prevent the liquid to fall from its natural flow. The present work proposes a new mechanistic model for the prediction of the onset of flooding in vertical and inclined pipes in the presence of obstructions, as well as taking into account the viscosity effect. The good performance of the model in the different geometrical conditions and for variable viscosities of the liquid component assesses the validity of the hypothesis that the instability of a wavelike disturbance limits the countercurrent flow in a channel. 相似文献