By simultaneously measuring flight forces and stroke kinematics in several species of fruit flies in the genus Drosophila, we have investigated the relationship between wing motion and aerodynamic force production. We induced tethered flies to vary their production of total flight force by presenting them with a vertically oscillating visual background within a closed-loop flight arena. In resp...

A time domain approach for predicting the coupled flutter and buffeting response of long span bridges is presented. The frequency dependent unsteady aerodynamic forces are represented by the convolution integrals involving the aerodynamic impulse function and structural motions or wind fluctuations. The aerodynamic impulse functions are derived from experimentally measured flutter derivatives, ...

Analysis of the aerodynamic forces acting on baseball pitches from major league games reveals a large variance in the measured coefficients of lift and drag. We have examined possible explanations for this effect and found that, while uncertainties introduced by measurement error and the method of reporting major league pitch trajectories do explain some of the spread, the reasons for the large...

In this paper, we compare the global accuracy of different strategies to build response surfaces by varying sampling methods and modeling techniques. The final application of the response surfaces being aerodynamic shape optimization, the test cases are issued from CFD simulations of aerodynamic coefficients. For comparisons, a robust strategy for model fit using a new efficient initialization ...

Vertical take-off and landing (VTOL) aircraft have become important aerial vehicles for various sectors, such as security, health, commercial sectors. These are capable of operating in different flight modes, allowing the covering most requirements environments. A tail-sitter is a type VTOL vehicle that has ability to take off land vertically on it elevators (its tail) or some rigid support ele...

In this study, density, energy, pressure, temperature changes, and drag coefficients occurring during the trajectory of movement for a 155 mm ammunition shell were simulated with computational flow dynamics software Stanford University Unstructured (SU2). Reynolds-Averaged Navier-Stokes (RANS) equations, which are operationally simplified variations (N-S) solver, used in simulations. The Reynol...