Numerical Simulation Study Of The Effect Of Key Washing Parameters On The Detergency Of Top-loading Washing Machines

The washing machine has gradually become an indispensable household appliance because it liberates people from heavy domestic work.With people’s rising expectations,the demand for the intelligence and efficiency of washing processes increases.Meeting such demands requires an in-depth study of the influence mechanisms on various washing parameters of washing machines.Therefore,this study conducts numerical simulation and experimental analysis of the washing process under different washing parameters.The main contents are as follows:(1)Study on fabric modeling method.The mass-spring model of fabric was analyzed from the perspectives of mechanics,mathematics,and contact models.The formulas for calculating the spring constants in the mass-spring model were derived through practical mechanical performance testing of the fabrics.Based on the actual test results,the values of each spring constant in the model were determined.(2)Study on washing process’ s numerical simulation method by using CFD-DEM.Appropriate turbulence calculation and multiphase flow models were selected based on the actual flow characteristics.Additionally,the geometric model of the flow field was established based on the actual structure of the top-loading washing machine(TLWM).This thesis analyzed the coupling algorithm of CFD and DEM methods and studied the meshing method for the near-wall zone and core region of the computational domain based on the coupling algorithm’s requirements for meshing.(3)Study on the evaluation method of detergency based on numerical simulation.Based on the results of simulation,this thesis selects the turbulence energy and the force working on particles as evaluation criteria for detergency and analyzes the influence mechanism of each washing parameter during the washing process.(4)Experimental study on the relationship between washing parameters and detergency.An experimental setup for TLWM was designed and built to investigate the influence of different washing parameters on detergency through experiments.Furthermore,the evaluation effectiveness of each evaluation criteria on detergency were analyzed by combining the results of simulation and experiments.