Several approaches for modelling the longitudinal aerodynamic coefficients of a fighter aircraft at high angles of attack, including the unsteady effects are presented. A traditional approach where the model of the coefficient arises in the form of the steady and unsteady effects, the unsteady effect being modelled by means of transfer functions. The second approach uses an internal variable de...

Design of muffler system strongly influences engine efficiency and noise level. Hence, comprehension of flow characteristics inside muffler system is very important. In this study, numerical study of three-dimensional steady and unsteady compressible flow inside muffler system attached to 4-cylinder engine was performed to identify the flow characteristics. To obtain the boundary conditions for...

The rating curve is the relationship between the water stage and the associated discharge in a givensection of a channel. In steady flow, this relationship usually has exponential type, whereas inunsteady it flow has a looped shape. Since direct developing of actual looped rating curve by usinghydrometric methods is merely possible, steady-state rating curve is commonly used as a downstreamboun...

the present work is focused on the performance analysis of a 1.7 liter engine with turbocharger. the ultimate target is studying the response of the turbocharger to the inlet pulsating flow. such numerical analysis requires the time variation of pressure and velocity at turbine inlet. in order to achieve such information, one dimensional unsteady viscous compressible flow within a 1.7 liter tur...

We give an algorithmic introduction to Lagrangian coherent structures (LCSs) using a newly developed computational engine, LCS Tool. LCSs are most repelling, attracting and shearing material lines that form the centrepieces of observed tracer patterns in two-dimensional unsteady dynamical systems. LCS Tool implements the latest geodesic theory of LCSs for two-dimensional flows, uncovering key t...

This research paper presents the CFD analysis of oscillating airfoil during pitch cycle. Unsteady subsonic flow is simulated for pitching airfoil at Mach number 0.283 and Reynolds number 3.45 millions. Turbulent effects are also considered for this study by using K-ω SST turbulent model. Two-dimensional unsteady compressible Navier-Stokes code including two-equation turbulence model and PISO pr...

The fluid-structure coupling process of a plunging rigid airfoil with a thin elastic plate attached at the trailing-edge is simulated numerically by using unsteady potential flow source/vortex panel method and the Euler-Bernoulli beam vibration differential equation. The flow characteristics, the unsteady aerodynamic loads, especially the thrust effects of the plunging motion are computed. The ...

This research paper presents the CFD analysis of oscillating airfoil during pitch cycle. Unsteady subsonic flow is simulated for pitching airfoil at Mach number 0.283 and Reynolds number 3.45 millions. Turbulent effects are also considered for this study by using K-ω SST turbulent model. Two-dimensional unsteady compressible Navier-Stokes code including two-equation turbulence model and PISO pr...

Propulsor crashback is an off-design operating condition where a propulsor rotates in the reverse direction to yield negative thrust. Crashback is characterized by the interaction of the free stream with the reverse flow generated by propulsor rotation. This causes a highly unsteady vortex ring which leads to flow separation and unsteady forces and moments on the blades. Large eddy simulation (...