In this work, a penalization method is discussed in the context of vortex methods for incompressible flows around complex geometries. In particular, we illustrate the method in two cases: the flow around a rotating blade for Reynolds numbers 1000 and 10,000 and the flow past a semi-circular body consisting of a porous layer surrounding a rigid body at Reynolds numbers 550 and 3000. In the latte...

This report details an experiment done to verify the effectiveness of a passive flow control system on a two-dimensional bluff body, blunt trailing edge model in controlling wake dimension and Karman vortex sheds. An earlier experiment by Park, et.al. [1] performed analysis via wind tunnel pressure testing and computerized model to determine the ideal proportions of such a tab design and identi...

The Blasius boundary layer solution is a basic feature of fluid mechanics, and the first application of Prandtl’s boundary layer concept as a significant issue in engineering. This work highlights the contributions of Blasius to hydrodynamics over a period of only six years, which marked the initiation of boundary layer theory. His main papers relating to aerodynamics and smooth turbulent pipe ...

The present study explores flow visualization experiments with various blunt shaped bluff bodies placed inside a circular pipe. The bodies mainly comprise of modifications of trapezoidal cylinder, most widely used in practical applications, such as vortex flowmeters. The present configuration possesses the feature of both internal and external flows with low aspect ratio. The vortex dynamics of...

ehicle technology at APL encompasses the four disciplines of guidance and control, navigation, aerodynamics/hydrodynamics, and propulsion as applied to military platforms and spacecraft. These disciplines are addressed in terms of historical background at APL, the status of current work, and examples of important new initiatives. The information was compiled for the Senior Leadership Team’s “Ve...

Bluff body calculation was accelerated by using a special-purpose computer, MDGRAPE-2, that was exclusively designed for molecular dynamics simulations. The three main issues were solved regarding the implementation of the MDGRAPE-2 on vortex methods. These issues were the efficient calculation of the Biot-Savart and stretching equation, the optimization of the table domain, and the round-off e...

A physical full-scale experimental set-up was designed and implemented in the wind tunnel to reproduce capture trajectories of falling water drops when approaching collector catching type precipitation gauges, reproducing rainfall measurements windy conditions. The experiment allowed collect, for first time, a large data set high-resolution footages deviation such trajectories, as induced by bl...