The Numerical Analysis On Temperature Field Of Descaling Plate And Flow Field In High-Pressure Water Descaling

Firstly, summary were made on high-water descaling method, the descaling mechanism and its influence factors in this thesis. Then, numerical simulation model of descaling process was discussed. Based on this, unsteady numerical simulations were proceeded in connection with single and double nozzle model.Temperature field was analysed in single nozzle model after testing and verifying the simulation results with references. In double nozzle model,not only temperature field was analysed but also velocity field was analysed influenced by three factors such as nozzle inlet velocity u, dimensionless impact distance H/D, nozzle exit half angleθ.Then,research works aiming at steady case were engaged in.In the foundation of numerical simulation, presented general criterion equation of the high-pressure descaling process by means of dimensional method and regression equation about Nu through least-squares analysis.. After simulation and analysis of the actual process, the conclusions is as follows:①With the increase of the nozzle inlet velocity,the cooling capacity of the water jet enhances owing to the augmentation of the convection heat transfer coefficient in the steel surface.②Along with the increase of the dimensionless impact distance, the convection heat transfer coefficient of the steel surface demonstrates the process of decrease, increase, decrease again, which illustrates there exists an optimal impact distance.③With the increase of the nozzle exit half angle, the cooling capacity of the water jet declines because of the reduction of the convection heat transfer coefficient in the steel surface. If the nozzle exit half angle is excessively small, the number of the nozzle will be added as a result of lacking covering of the steel surface, leading to waste of the resources. It can be inferred that there exists an optimal nozzle exit half angle.④Distinct from the result of single nozzle model,in the double nozzle model, the offset phenomenon of the stagnation point can be observed by reason of the perturbation and entrainment of the two water jet.⑤The regression analysis show that Nu has the best correlation with Re.