Aerodynamic shape design optimization problems, such as inverse and constrained airfoil design and axisymmetric nozzle design, are investigated by applying the simultaneous perturbation stochastic approximation (SPSA) method to objective functions that are estimated during each design iteration using a finite volume computational fluid dynamics technique for solving the compressible Navier–Stok...

Aspects of the development process of a flight simulation environment within a Simulink Project are presented. In particular, special attention is given to the control surfaces for longitudinal motion for three different trailing-edge control surface configurations, which differ in number and spanwise size of the individual surfaces. The entire modeling and simulation process consists of four m...

The structural and aerodynamic performance of the air inlet volute has an important influence on the performance of the gas turbine. On one hand, it requires the airflow flowing through inlet volute as even as possible, in order to reduce the pressure loss, to avoid a decrease in the effective output power and an increase of the fuel consumption rate of the internal combustion engine which indi...

A multidisciplinary research effort that combines aerodynamic modeling and gain-scheduled control design for aircraft flight at post-stall conditions is described. The aerodynamic modeling uses a decambering approach for rapid prediction of post-stall aerodynamic characteristics of multiple-wing configurations using known section data. The approach is successful in bringing to light multiple so...

A study was undertaken at NASA Langley Research Center to establish, demonstrate, and apply methodology for modeling and implementing the aerodynamic effects of MANPADS damage to a transport aircraft into real-time flight simulation, and to demonstrate a preliminary capability of using such a simulation to conduct an assessment of aircraft survivability. Key findings from this study include: su...

Bats are the only mammals capable of flight, and they are the only animal flyers that are mammals. This thesis focuses on the latter of those facts, and investigates how bats fly, from an aerodynamic perspective. The data on which this thesis is based were generated by examining the airflows beneath and behind bats flying in a wind tunnel, and by examining their wing kinematics manually and aut...

We examine how litter mass in bats varies with respect to wing loading, an important aerodynamic aspect of flight. From geometric proportions, litter mass should scale to wing loading by an exponent of three. Conversely, analysis of aerodynamic consequences of carrying extra mass suggests that an exponent significantly less than three would be selectively advantageous. Our results show that Meg...

We have developed a numerical simulation methodology that is able to accurately characterize the focusing performance of aerodynamic lens systems. The commercial computational fluid dynamics (CFD) software FLUENT was used to simulate the gas flow field. Particle trajectories were tracked using the Lagrangian approach. Brownian motion of nanoparticles was successfully incorporated in our numeric...

On the basis of small axial fan with five blades, 6 types of small axial flow fans with different chord lengths splitter blades were designed. Numerical simulation of 6 fan models with splitter blades and prototype fan were done by using Fluent. Based on the obtained simulation results, internal flow characteristics and aerodynamic noise were analyzed and compared. It indicates that: splitter b...