A numerical model to predict the temperature field in a hermetic reciprocating compressor for household refrigeration appliances is presented in this work. The model combines a high resolution three-dimensional heat c...A numerical model to predict the temperature field in a hermetic reciprocating compressor for household refrigeration appliances is presented in this work. The model combines a high resolution three-dimensional heat conduction formulation of the compressor＇s solid parts, a three-dimensional CFD （computational fluid dynamics） approach for the gas line domain and lumped formulations of the shell gas and the lubrication oil. Heat transfer coefficients are determined by applying CFD to the gas line side and correlations from the literature on the shell gas and oil side, respectively. The valve in the gas line simulation is modelled as a parallel moving fiat plate. By means of an iterative loop the temperature field of the solid parts acts as boundary condition for the CFD calculation of the gas line which returns a cycle averaged quantity of heat to the solid parts. Using an iteration method which is based on the temperature deviation between two iteration steps, the total number of iterations and consequently the computational time can be reduced. The loop is continued until a steady-state temperature field is obtained. Calculated temperatures of the solid parts are verified by temperature measurements of a calorimeter test bench.展开更多
A two-dimensional steady state model was developed and solved numerically to predict the performance of evaporative condensing regenerator.Two-dimensional parameter distributions of air,solution and refrigerant were c...A two-dimensional steady state model was developed and solved numerically to predict the performance of evaporative condensing regenerator.Two-dimensional parameter distributions of air,solution and refrigerant were calculated by the mathematical model.The solution content first increases and then decreases along the solution flow direction.At y/Hr=0.98(where Hr is the height of regenerator),air humidity increases from 1.99% to 2.348% firstly and then decreases.The experimental results were used to validate mathematical model.It is indicated that the simulation results agree with experimental data well.The results not only show that the mathematical model can be used to predict the performance of regenerator,but also has great value in the design and improvement of evaporative condensing regenerator.展开更多
A theoretical and numerical study has been performed on an air film dumper attached to a plate structure. Combined with the analysis by Fox and Whittorg a damping model of the air fiim damper has been developed. A com...A theoretical and numerical study has been performed on an air film dumper attached to a plate structure. Combined with the analysis by Fox and Whittorg a damping model of the air fiim damper has been developed. A complex stiffness was introduced to represent the air pressure in the damper cavity. The stain energy and dissipated energy were integrated from the real part and imaginary part of the complex stiffness to determine the stiffness and damping. The response of the plate with the air film damper was considered by treating the air film as multiple discrete damping-stiffness elements using ANSYS.展开更多
文摘A numerical model to predict the temperature field in a hermetic reciprocating compressor for household refrigeration appliances is presented in this work. The model combines a high resolution three-dimensional heat conduction formulation of the compressor＇s solid parts, a three-dimensional CFD （computational fluid dynamics） approach for the gas line domain and lumped formulations of the shell gas and the lubrication oil. Heat transfer coefficients are determined by applying CFD to the gas line side and correlations from the literature on the shell gas and oil side, respectively. The valve in the gas line simulation is modelled as a parallel moving fiat plate. By means of an iterative loop the temperature field of the solid parts acts as boundary condition for the CFD calculation of the gas line which returns a cycle averaged quantity of heat to the solid parts. Using an iteration method which is based on the temperature deviation between two iteration steps, the total number of iterations and consequently the computational time can be reduced. The loop is continued until a steady-state temperature field is obtained. Calculated temperatures of the solid parts are verified by temperature measurements of a calorimeter test bench.
基金Project(PHR201007127) supported by Academic Human Resources Development Fund of Institutions of Higher Learning under the Jurisdiction of Beijing Municipality, China Project(bsbe2010-05) supported by the Opening Funds of State Key Laboratory of Building Safety and Built Environment, China Project supported by the Doctoral Startup Foundation of Beijing University of Civil Engineering and Architecture, China
文摘A two-dimensional steady state model was developed and solved numerically to predict the performance of evaporative condensing regenerator.Two-dimensional parameter distributions of air,solution and refrigerant were calculated by the mathematical model.The solution content first increases and then decreases along the solution flow direction.At y/Hr=0.98(where Hr is the height of regenerator),air humidity increases from 1.99% to 2.348% firstly and then decreases.The experimental results were used to validate mathematical model.It is indicated that the simulation results agree with experimental data well.The results not only show that the mathematical model can be used to predict the performance of regenerator,but also has great value in the design and improvement of evaporative condensing regenerator.
文摘A theoretical and numerical study has been performed on an air film dumper attached to a plate structure. Combined with the analysis by Fox and Whittorg a damping model of the air fiim damper has been developed. A complex stiffness was introduced to represent the air pressure in the damper cavity. The stain energy and dissipated energy were integrated from the real part and imaginary part of the complex stiffness to determine the stiffness and damping. The response of the plate with the air film damper was considered by treating the air film as multiple discrete damping-stiffness elements using ANSYS.
