Flow and heat transfer inside a nonisothermal, incompressible, thin-Ž lm squeezing bearing are analyzed. The governing equationshave been nondimensionalizedand reduced to simpler forms based on an order of magnitude analysis. Various analytical solutions for the temperature distribution and Nusselt number under dierent physical constraints are obtained. The in uence of the thermal squeezing pa...

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 (...

Unsteady flow models of wings and airfoils have been studied to understand the aerodynamic performance of natural flyers and provide improved maneuverability for micro aerial vehicles (MAVs). Vortex methods have been extensively applied to reduce the dimensionality of these aerodynamic models, based on the proper estimation of the distribution and evolution of the vortices in the wake. In such ...

We apply the phase-reduction analysis to examine synchronization properties of periodic fluid flows. The dynamics of unsteady flows are described in terms of the phase dynamics reducing the high-dimensional fluid flow to its single scalar phase variable. We characterize the phase response to impulse perturbations, which can in turn quantify the influence of periodic perturbations on the unstead...

The paper presents an adjoint based approach for determining global error in the time domain that is relevant to scalar outputs computed as functions of the unsteady flow solution. The algorithm is derived for the unsteady Euler equations and takes into account the effect of dynamic meshes. Two primary components of the total error are specifically identified, namely, the error due to temporal ...