Rotating cavitation is one of the flow instabilities associated with cavitation, which has been a problem for the development of turbopumps of liquid rocket engines since it causes super-synchronous shaft vibration. Recently, it is argued that rotating cavitation might also cause large repetitive stresses on blades. This paper describes about the theoretical prediction of unsteady blade forces ...

Small planktonic organisms ubiquitously display unsteady or impulsive motion to attack a prey or escape a predator in natural environments. Despite this, the role of unsteady forces such as history and added mass forces on the low-Reynolds-number propulsion of small organisms, e.g. Paramecium, is poorly understood. In this paper, we derive the fundamental equation of motion for an organism swim...

entropy generation in an unsteady hydromagnetic couette flow of a viscous incompressible electrically conducting fluid between two infinite horizontal parallel plates in a rotating system have been analyzed. both the lower and upper plates of the channel are subjected to asymmetric convective heat exchange with the ambient following the newton's law of cooling. a numerical solution for governin...

We show how a stable and accurate hybrid procedure for fluid flow can be constructed. Two separate solvers, one using high order finite difference methods and another using the node-centered unstructured finite volume method are coupled in a truly stable way. The two flow solvers run independently and receive and send information from each other by using a third coupling code. Exact solutions t...

A new type of glyph is introduced to visualize unsteady flow with static images, allowing easier analysis of time-dependent phenomena compared to animated visualization. Adopting the visual metaphor of radar displays, this glyph represents flow directions by angles and time by radius in spherical coordinates. Dense seeding of flow radar glyphs on the flow domain naturally lends itself to multi-...

This paper presents simulations of unsteady flow past a plunging airfoil using the highorder spectral difference (SD) method. Both third-order and fourth-order SD methods are used on unstructured quadrilateral grids. The vortex shedding pattern of an airfoil in an oscillating plunge motion becomes asymmetric at a sufficiently high frequency. The SD method is able to capture this effect and reve...

Feature-based flow visualization is naturally dependent on feature extraction. To extract flow features, often higher-order properties of the flow data are used such as the Jacobian or curvature properties, implicitly describing the flow features in terms of their inherent flow characteristics (e.g., collinear flow and vorticity vectors). In this paper we present recent research which leads to ...

The work develops a high-accuracy viscous analysis of nonlinear aeroelastic interaction of a Micro Air Vehicle’s (MAV) wing section with a non-uniform, unsteady upstream flow. In the implemented iterative procedure, a set of governing Navier-Stokes equations is solved simultaneously with nonlinear equations of motion of the structure, so that the fluid and structure are treated as a coupled dyn...

The unsteady aerodynamic behavior of a bird-damaged fan stage at the inlet of a highbypass turbofan engine is examined with a computational fluid dynamics (CFD) aerodynamic model suitable for use in an aeroelastic response calculation. ANSYS CFX, a commercially available CFD solver, is utilized to perform the steady-state and unsteady CFD calculations for the undamaged and damaged fan. The dama...

INTRODUCTION The discharge ofliquids from vertical tubes with various con­ traction geometries was studied via the unsteady Bernoulli equa­ tion. The temporal variations of the exit velocity and fluid level in the tube were found from the numerical integration of nonlin­ ear differential equations. Sudden, quadratic, and exponential contraction geometries were considered. For inlet to exit area...