A robust unsteady rotor flowfield solver CLORNS code is established to predict the complex aerodynamic characteristics of flowfield. In order handle difficult problem about grid generation around with shape in this CFD code, a parameterized generated method established, and moving-embedded grids are constructed by several proposed universal methods. work, Reynolds-Averaged Navier-Stokes (RANS) equations Spalart-Allmaras selected as governing helicopter rotor. The discretization convective...

Expanding the imaging field of view (FOV) medical ultrasound transducers will be more effectively detect pathological behaviors tissues or organs. Conventional rigid can realized by increasing number array elements curvature, however, aperture is fixed original size and shape during manufacturing process. This paper presented a 128-element, 3MHz flexible curvature abdominal (FCAA) with goal dynamically expanding FOV within 120° range. The piezoelectric stack was divided into small pitches...

The aerodynamic performance analysis and blade planform design of a coaxial rigid rotor in forward flight were carried out utilizing CFD solver CLORNS. Firstly, the flow field characteristics analyzed. Shock-induced separation occurs at advancing side tip severe reverse retreating root. Then, influence geometrical parameters on was investigated. Results show that swept-back could reduce compressibility drag elliptic shape optimize airload distribution high advance ratio flights. A kind...

A solver is developed aiming at efficiently predicting rotor noise in hover and forward flight. In this solver, the nonlinear near-field solutions are calculated by a hybrid approach which includes Navier–Stokes Euler equations based on moving-embedded grid system adaptive methodology. combination of third-order upwind scheme flux-difference splitting scheme, instead second-order center-difference may cause larger wake dissipation, has been employed present computational fluid dynamics (CFD)...

To investigate the distinct properties of helicopter rotors during circling flight, aerodynamic and dynamic models for main rotor are established considering trim conditions flight parameters helicopters. The free wake method is introduced to compute unsteady loads characterized by distortions wakes, modal superposition used predict overall structural rotor. effectiveness methods verified comparison with experimental results, whereby influences direction, radius, velocity evaluated in both...

A design strategy to provide suitable baseline prop-rotors for sophisticated applications is presented. Unlike those approaches aimed at improving the aerodynamic performance of an already refined blade by high-fidelity methods, new can efficiently work out proper configurations with no baseline. It introduced through process initial blades a small uncrewed tilt-rotor aircraft. Moreover, consists four main parts, including identifying ideal boundaries chord and twist distributions under...

The external aerodynamics plays an important role in the design process of any automotive. whole performance vehicle can be improved with help aerodynamics. aerodynamic analysis nowadays is implemented recent research automotive industry to achieve better cars terms and efficiency. major objective present work find out effect changing angle between engine hood front windshield on reducing car air resistance. A full scale three dimensional (BMW 3 series) sedan model was carried using ALIAS...

Based on the numerical calculation and analysis of principle lift thrust Fan-wing. A new scheme for wing Fan-wing aircraft-distributed jet blowing was presented. Firstly, mechanism formation process vortex-induced force two kinds wings analyzed. Then, method validation example were verified. It proved that distributed had same mode as by comparing relative static pressure distribution curve, velocity contours, contours. Finally, blow-up speed a defined relationship between with flow angle...

A conventional axial turbine drived by a pulse detonation combustor heavily challenges the cooling and hot gas sealing. In order to fully understand physical behavior of ingress egress effect with inlet mainstream, study is carried out investigate unsteady flow field sealing efficiency inside cavity using method unsteady, 3-D CFD simulation. The inflow boundary condition simplified simple exponential decay formulas are applied mainstream passage. results reveal that magnitude pressure does...

This paper describes the aerodynamic simulation and optimization of NACA 0012 airfoil at a low Reynolds number using unsteady Reynolds-averaged Navier-Stokes (URANS) Spalart–Allmaras turbulence model in Ansys Fluent. The purpose this is to simulate optimize get better performances numbers. Parsec method was selected for airfoil. Both these airfoils are simulated CFD Fluent between 0 13-degree angle attack 200000. To airfoil, mesh generation crucial so an O-grid structured created. After...

Rotating instability (RI) as a prestall wave is closely related to tip clearance noise, blade vibration and rotating stall/surge of axial compressors, so lots researchers have focused on it. In this paper, the experimental numerical investigations for subsonic compressor are carried out explore flow mechanism leading step change in aerodynamic modes instabilities at different rotor speeds. The measurement results show that RIs only appear operating points narrow mass range near stability...

Electrohydrodynamic (EHD) force produced by corona discharge is considered as a new thrust for solar-powered aircraft and stratosphere balloons in near space. However, its performance at low air pressures remains to be clarified. An experiment of measuring the EHD 0.02 atm–1.0 atm (1 = 1.01325×10 5 Pa) carried out with wire-to-cylinder geometric structure. The ion distribution analyzed using drift-diffusion model two-dimensional numerical simulation. experimental result shows that not...

In modern campaign, Aircraft maneuverability and agility have been playing an increasingly important role. Plasma thrust vector control can avoid shortcomings of traditional methods, it has a very good prospect.In present work CFD simulation for 2D nozzle is performed.The results showed that the change magnetic field impress turn flowfield.