A computational investigation was performed to predict the effects of aerodynamic performance degradation on aircraft swept taper wing with and without 10 minutes and 22.5 minutes glaze ice accretions. In this study, ...A computational investigation was performed to predict the effects of aerodynamic performance degradation on aircraft swept taper wing with and without 10 minutes and 22.5 minutes glaze ice accretions. In this study, the three-dimensional simulated glaze ice shapes were defined from a series of two-dimensional ice sections. The aerodynamic performances of glaze iced swept wings with C-H structure multi-block grid were analyzed and evaluated. The steady Reynolds- Averaged Navier-Stokes （RANS） equations are employed to compute solutions with implementation of two equation Shear-Stress Transport （SST） turbulence model and second-order upwind differencing for entire iced wing flow field. Computed results were compared with available experimental data. The CFD computation can also accurately predict the aerodynamic performance degradation of lift, drag and pressure coefficients of finite swept wing with glaze ice accretions which have two big upper and lower horn.展开更多
Computational fluid dynamics(CFD)simulations of multi-lobe progressive cavity(PC)pumps are limited in the literature due to the geometric complexity of the pump,which places numerous restrictions on the grid generatio...Computational fluid dynamics(CFD)simulations of multi-lobe progressive cavity(PC)pumps are limited in the literature due to the geometric complexity of the pump,which places numerous restrictions on the grid generation process.The present study attempts to alleviate such restrictions by developing a detailed numerical procedure for the numerical simulations of multi-lobe progressive cavity pumps.The profile equations for the multi-lobe configuration at any section at each instant of rotation are presented.A structured grid generation method is developed to generate mesh files required for CFD simulations of multi-lobe PC pumps.Results from the present procedure are validated against single-lobe PC pump numerical results available in the literature.Finally,a numerical parametric study is carried out to investigate the effect of the number of lobes,the stator pitch,the circular fillet and clearance on the volumetric efficiency of PC pumps with viscous oils.展开更多
文摘A computational investigation was performed to predict the effects of aerodynamic performance degradation on aircraft swept taper wing with and without 10 minutes and 22.5 minutes glaze ice accretions. In this study, the three-dimensional simulated glaze ice shapes were defined from a series of two-dimensional ice sections. The aerodynamic performances of glaze iced swept wings with C-H structure multi-block grid were analyzed and evaluated. The steady Reynolds- Averaged Navier-Stokes （RANS） equations are employed to compute solutions with implementation of two equation Shear-Stress Transport （SST） turbulence model and second-order upwind differencing for entire iced wing flow field. Computed results were compared with available experimental data. The CFD computation can also accurately predict the aerodynamic performance degradation of lift, drag and pressure coefficients of finite swept wing with glaze ice accretions which have two big upper and lower horn.
文摘Computational fluid dynamics(CFD)simulations of multi-lobe progressive cavity(PC)pumps are limited in the literature due to the geometric complexity of the pump,which places numerous restrictions on the grid generation process.The present study attempts to alleviate such restrictions by developing a detailed numerical procedure for the numerical simulations of multi-lobe progressive cavity pumps.The profile equations for the multi-lobe configuration at any section at each instant of rotation are presented.A structured grid generation method is developed to generate mesh files required for CFD simulations of multi-lobe PC pumps.Results from the present procedure are validated against single-lobe PC pump numerical results available in the literature.Finally,a numerical parametric study is carried out to investigate the effect of the number of lobes,the stator pitch,the circular fillet and clearance on the volumetric efficiency of PC pumps with viscous oils.
