Simulation And Experimental Study On Cooling Process Of Heavy Cylinder Based On Spray Cooling

Heavy cylinder is the core basic component of major technical equipment in the nuclear power,petrifaction,and other energy fields and plays a key role in the stable operation of major equipment.With the development of large equipment manufacturing industry,the demand for heavy cylinder is also increasing,and its inefficient manufacturing process and product quality have been severely tested.In this paper,in view of the poor cooling capacity and low efficiency of the traditional heat treatment cooling process,simulation and experimental are studied on heavy cylinder spray cooling device and cooling process.The mathematical model of temperature field and stress field is established for the numerical simulation of heavy cylinder spray cooling.Established heat transfer coefficient calculation model of heavy cylinder spray cooling,the air cooling coefficient and the deep cooling coefficient of the water tank.The CCT and TTT transition curves of2.25Cr1Mo0.25 V steel are given,which provides a theoretical basis for the formulation of the subsequent cooling process.A method for designing heavy cylinder spray cooling device structure is proposed,and a heavy cylinder spray cooling device with adjustable position is designed.Calculate cylinder spray cooling heat transfer coefficient.Formulate cooling process preliminarily.Simulation of heavy cylinder spray cooling process based on Ansys Workbench software.The simulation results show that the axial temperature uniformity is good,the temperature difference between the cylinder section of the thickness direction is obvious,and the thermal stress is within the material bearing range during cylinder cooling process.Based on the orthogonal test,the numerical simulation scheme for the spray cooling process under the combination of different equipment process parameters is designed.The effects of water flow density?spray pressure?spray angle and spray time and gap time ratio of cooling section on the temperature uniformity,thermal stress,and cooling time were studied,determined the optimal parameter combination.Optimize the cylinder spray cooling process further,and making comparison and analysis of the deep cooling processof the traditional water tank,the results show that the cylinder temperature uniformity of the spray cooling process is better,cooling time is greatly reduced,and the thermal stress is also within the range of the cylinder material.The physical experiment is carried out for the rapid cooling process of heavy cylinder spray cooling,measure the grain size and mechanical properties of the cylinder in the thickness direction.The experimental results show that the grain size and mechanical properties of the cylinder with spray cooling heat treatment technology all meet the requirements of operation,and further verify the feasibility of the rapid cooling process based on spray cooling.