Process Optimization And Numerical Simulation For PTC Heater Based On FLUENT

PTC electric heater refers to using a Positive Temperature Coefficient of heat sensitive materials as the heater heating elements,It has the advantages of low heat resistance and high efficiency of heat transfer,widely used in the fields of household appliances,electrical equipment and so on.Electric cars rely on electricity,not enough heat from the engine to warm them up,It is impossible to use the traditional fuel system to make heat,and the development of electric cars must be developed for the heating system.The article uses electric car PTC water heater as the research object,and analyses the flow speed and temperature change law of the import and export by heat energy transfer and energy conservation equation.The three-dimensional numerical simulation of the internal flow field during the working process of PTC water heaters was simulated using the fluid dynamics software Fluent.Finally with the orthogonal experiment method to physical experiments analysis,compare the numerical simulation and experiment,test and verify the reliability of data,for PTC run the initial process parameters optimization provides scientific guidance and theoretical basis.Modeling processing in Gambit software before using fluent software,and set the boundary conditions and mesh,mesh density can be adjusted according to the different situation,selecting the best mesh density.In computational fluid dynamics,the use of the Fluent software in a Mixture models of multiphase flow.The internal flow field in the electric car of the PTC water heater have the three-dimensional numerical simulation analysis.It obtains changing rule and influencing factors of the PTC water heater of temperature field?velocity field and pressure field,by comparing the different turbulence intensity and speed under the condition of the internal flow field in the PTC water heater.It is that turbulent intensity of 40%,0.8m/s speed,initial temperature 35.8? in the simulation analysis of initial solution Provided in the manufacturer.Simulation results show that due to the PTC water heater tank wall has certain thickness,the initial scheme under the heating effect is not obvious and the heating speed is slow,heating conditions are consistent with the actual result of simulation,the simulation analysis proves that the FLUENT to simulate the PTC water heater research and production is of high reference value,and verified the accuracy of the analysis.It is to solve the PTC water heater heating effect not obviously,simulated test was performed On temperature field?pressure field and velocity field three variable parameters.Through the comparison between results of simulation experiments and analysis and determine the best solution:turbulent intensity of 60%,1 m/s speed and initial temperature of 38.8?.Best solutions and the initial simulation results contrast analysis shows that the higher turbulent intensity,the flow speed and initial temperature can accelerate the rate of flow,more heat could be sent at the same time,make the heating effect is better.Finally,the experiment of the PTC water heater,The experiment by orthogonal simulation experiment to determine the best process,its significance lies in can be more intuitive to explore the initial temperature,velocity and turbulence intensity of the three different variables of the PTC water heater heating effect.By experiment,under the condition of the turbulence intensity60%,speed1m/s,the initial temperature of 38.8?,the PTC water heater heating speed and heating temperature,to verify the reliability of numerical simulation of the PTC water heater once again.It provides the theoretical basis and technical guidance for mass production of the PTC water heater.