| With the constant improvement of the automatic degree and development of the Process Technology, the control valve has already been widely applied to metallurgy, electricity, chemical industry, petroleum, textile in the industrial department. The control valve is essential in control system, In the process control industry the most commonly used terminal control part is a control valve, it is the important link which makes up industry's automated system, Is called it the production process automation "the hands and feet". The control valve accepts the standard control signal, Will control the signal to turn the corresponding mechanical displacement, change the area of circulation of the valve, thus achieve to the control purpose to accuse of target's parameter (pressure, flow, temperature, liquid level, etc. ), guarantee continuous process control system, effective in normal operation.The control valve is the products using the most questions in the industrial automation instrument, The control valve in many varieties and specifications, low reliability, the flow characteristic of the control valve industrial process plant characteristics are not matching, causing deterioration of the control system quality, the control valve is energy-consuming equipment, we should reduce the energy consumption of the regulating valve, improve the utilization ratio of the energy.Computational fluid dynamics (CFD) regards computer as the simulation means, utilizes the certain computation technology to seek hydromechanics each kind of complex question the separate numerical solution. CFD in the design of products made in the structural design tends to be more reasonable. In recent years, CFD numerical simulation has been applied in the valve design.Main work of this text:First, in view of the use widespread some type parameter cage control valve, use the three-dimensional modeling software to establishment valve interior flow field model, through CFD preprocessor production computation grid, using CFD software to separate solve, may obtain the regulating valve interior flow field the visible graph, like pressure and velocity vectors chart, contour map and so on. With make one degree of flow of making through the numerical simulation, receiving the flow characteristic of the control valve, carries on the comparison and analysis with the experimental determination data. Obtains the conclusion is the model which this article constructs is correct and reliable.Second, Take the goal of reduces the turbulent kinetic energy and the turbulent dissipation rates, optimize the energy loss serious site, after optimizes the flow channel to carry on the numerical simulation, comparison with the improvement before flow channel numerical simulation and obtains the optimized improvement model and the convection one optimized suggestion are putting forward.After numerical simulation can be obtain flow characteristic curve and the three-dimensional flow in detail. The advantage of CFD numerical simulation especially displays in the development of the new products, it not only can replace theroutine experiment and offer various kinds of flow characteristic parameters by a large margin , It not only can replace conventional experimental substantially provide various flow parameters, and reveals through three-dimensional flow field pattern to optimize design based on detailed. CFD numerical simulation in this text applications will greatly enhance the cage control valve design and the technical level and product quality, reducing cage control valve design and processing cycle, significant cost savings, And optimizes through the flow channel, to reduce fluid flow through the valve of energy loss, improving efficiency in the use of energy have the extremely vital significance.
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