Lifting-line model is developed for a propeller of large aspect ratio inblade-attached noninertial system. In the analysis of the method of matched asymptoticexpansions, a fictitious velocity potential is introduced. ...Lifting-line model is developed for a propeller of large aspect ratio inblade-attached noninertial system. In the analysis of the method of matched asymptoticexpansions, a fictitious velocity potential is introduced. Control equation, boundarycondition and Bernoulli equation are derived in blade- attached system. The analysis ofthe matched asymptotic expansions shows that if the advance ratio of propeller is notvery small, lifting-line theory is still valid in blade-attached noninertial system for propeller.展开更多
Direct numerical simulation(DNS)of transition over a hypersonic lifting body model HyTRV developed by China Aerodynamics Research and Development Center is performed.The free-stream parameters are:the free-stream Mach...Direct numerical simulation(DNS)of transition over a hypersonic lifting body model HyTRV developed by China Aerodynamics Research and Development Center is performed.The free-stream parameters are:the free-stream Mach number is 6,the unit Reynolds number is 10000/mm,the free-stream temperature is 79 K,the angle of attack is 0,and the wall temperature is 300 K.Weak random blowing-and-suction perturbations in the leading range are used to trigger the transition.A high order finite-difference code OpenCFD developed by the authors is used for the simulation,and grid convergence test shows that the transition locations are grid-convergence.DNS results show that transition occurs in central area of the lower surface and the concaved region of the upper surface,and the transition regions are also the streamline convergence regions.The transition mechanisms in different regions are investigated by using the spectrum and POD analysis.展开更多
Deformities in the body contouring population are rarely isolated to one area,and procedures can be combined to achieve more substantial results.While there is no formula for optimal surgical sequencing and timing,the...Deformities in the body contouring population are rarely isolated to one area,and procedures can be combined to achieve more substantial results.While there is no formula for optimal surgical sequencing and timing,there are certain principles which-when applied appropriately-can yield results that are reliable,aesthetically pleasing,and aligned with the patient’s desires and preferences.In this article,we outline our latest thinking in circumferential body contouring and how to integrate the lower body lift with procedures of the abdomen,upper body,breasts,back,and arms to achieve the complete 360°look.展开更多
文摘Lifting-line model is developed for a propeller of large aspect ratio inblade-attached noninertial system. In the analysis of the method of matched asymptoticexpansions, a fictitious velocity potential is introduced. Control equation, boundarycondition and Bernoulli equation are derived in blade- attached system. The analysis ofthe matched asymptotic expansions shows that if the advance ratio of propeller is notvery small, lifting-line theory is still valid in blade-attached noninertial system for propeller.
基金supported by the National Numerical Windtunnel Projectthe National Key Research and Development Program of China(Grant Nos.2016YFA0401200,2020YFA0711800 and 2019YFA0405300)the National Natural Science Foundation of China(Grant No.91852203 and Grant No.12072349).
文摘Direct numerical simulation(DNS)of transition over a hypersonic lifting body model HyTRV developed by China Aerodynamics Research and Development Center is performed.The free-stream parameters are:the free-stream Mach number is 6,the unit Reynolds number is 10000/mm,the free-stream temperature is 79 K,the angle of attack is 0,and the wall temperature is 300 K.Weak random blowing-and-suction perturbations in the leading range are used to trigger the transition.A high order finite-difference code OpenCFD developed by the authors is used for the simulation,and grid convergence test shows that the transition locations are grid-convergence.DNS results show that transition occurs in central area of the lower surface and the concaved region of the upper surface,and the transition regions are also the streamline convergence regions.The transition mechanisms in different regions are investigated by using the spectrum and POD analysis.
文摘Deformities in the body contouring population are rarely isolated to one area,and procedures can be combined to achieve more substantial results.While there is no formula for optimal surgical sequencing and timing,there are certain principles which-when applied appropriately-can yield results that are reliable,aesthetically pleasing,and aligned with the patient’s desires and preferences.In this article,we outline our latest thinking in circumferential body contouring and how to integrate the lower body lift with procedures of the abdomen,upper body,breasts,back,and arms to achieve the complete 360°look.