Breeder Genetic Algorithms represent a class of random optimisation techniques gleaned from the science of population genetics, which have proved their ability to solve hard optimisation problems with continuous parameters. In this paper we test a parallel version of this technique against a sequential Breeder Genetic Algorithm on a typical inverse design problem in Aerodynamics, the problem of...

Introduction This discussion is a qualitative treatment of a topic that is usually treated rigorously and quantitatively in engineering textbooks. This discussion is intended for the general audience of nonspecialists and will attempt to convey the main ideas behind aerodynamics of spheres in a qualitative manner, with a minimum number of mathematical equations. As the Latin roots of the word i...

466 NOTICES OF THE AMS VOLUME 47, NUMBER 4 The applied mathematics community suffered a great loss with the death of one of its leaders, Julian D. Cole, on April 17, 1999, at the age of 74. Julian was born in Brooklyn, New York, on April 2, 1925. He received his B.S. in engineering from Cornell and his Ph.D. from Caltech, where he worked with Hans Liepmann. During his career he was a faculty me...

Motivated by our interest in unsteady aerodynamics of insect flight, we devise a computational tool to solve the Navier–Stokes equation around a two-dimensional moving wing, which mimics biological locomotion. The focus of the present work is frequency selection in forward flapping flight. We investigate the time scales associated with the shedding of the trailingand leading-edge vortices, as w...

The purpose of this research is to develop a MATLAB model which can calculate the aerodynamics, such as lift, drag, and pressure, on an airfoil as it changes shape. This model needs to be computationally efficient and should have reasonable accuracy. A constant strength doublet panel code, which takes thickness and camber distribution as inputs, is used to model the aerodynamics. This code has ...

According to Slotnick et al. (2014), in 2025, air transport will contribute 1.5 billion tonnes of CO2 emissions annually. Of course, there are many other fluid dynamic engineering systems and processes that contribute to environmentally damaging emissions. Hence, it is critical to study aerodynamics with the view to creating more energy-efficient systems. Broadly speaking, the design engineer h...

We establish the existence, stability, and asymptotic behavior of transonic flows with a transonic shock for the steady, full Euler equations in two-dimensional infinite nozzles of slowly varying cross-sections. Given a smooth incoming flow that is close to a uniform supersonic state at the entrance, we prove that there exists a transonic flow whose infinite downstream smooth subsonic region is...

We present fully general relativistic equations governing viscous transonic flows in vertical equilibrium in Kerr geometry. We find the complete set of global solutions (both for Optically thick and optically thin flows) in the weak viscosity limit. We show that for a large region of parameter space, centrifugal pressure supported standing shocks can form in accretion and winds very close to th...