The effect of wing flexibility on aerodynamic force production has emerged as a central question in insect flight research. However, physical and computational models have yielded conflicting results regarding whether wing deformations enhance or diminish flight forces. By experimentally stiffening the wings of live bumblebees, we demonstrate that wing flexibility affects aerodynamic force prod...

Structural instability caused by self exciting aerodynamic forces (flutter) can be used as an effective input source for small scale energy harvesters. The self exciting aerodynamic force exerted on a T-shape cantilever causes periodic vibration, which can be converted into electric power through an electromagnetic transducer. Due to the complexities inherent in the fluid-structure interaction ...

In this paper, topology optimisation is applied to the design of the rear fuselage of an unmanned aerial vehicle (UAV). A comparison is drawn between the performance of a design created through evolutionary structural optimisation (ESO) and a baseline design modelled on a manually designed and successfully flow fuselage geometry, for different wing shapes. The loading for each wing shape is det...

This research describes aerodynamic characteristics of small-scale wind turbine blade, called Archimedes spiral wind turbine blade. Numerical approaches on the prediction of aerodynamic performance of the blade have been conducted. Both steady and unsteady state numerical simulations using ANSYS CFX are performed on the several cases of rotating speeds. Large scale tip vortex is captured and gr...

Horizontal axis wind turbines suffer from aerodynamic inefficiencies in the blade root region (near the hub) due to several non-aerodynamic constraints. Aerodynamic interactions between turbines in a wind farm also lead to significant loss of wind farm efficiency. A new dual-rotor wind turbine (DRWT) concept is proposed that aims at mitigating these two losses. A DRWT is designed that uses an e...

Fuel minimum range cruise of aircraft with high aerodynamic ef-ciency is considered as an optimal periodic control problem. Optimality conditions for trajectories with singular arcs and state variable constraints are derived. Computation of periodic optimal trajectories in the case addressed presents strong requirements on the numerical algorithm. Computational diiculties become larger when aer...

3. Applicable Pollutants: Particulate Matter (PM), including particulate matter less than or equal to 10 micrometers (μm) in aerodynamic diameter (PM10), particulate matter less than or equal to 2.5 μm in aerodynamic diameter (PM2.5), and hazardous air pollutants (HAPs) that are in particulate form, such as most metals (except mercury is the notable exception, as a significant portion of emissi...

Aerodynamic shape optimization involves designing the most efficient shapes of bodies that move through fluids. An optimization algorithm perturbs the shape of an airfoil until it finds the shape which best exhibits a given design objective. For an inverse design technique, this objective is a prescribed aerodynamic distribution, usually the surface pressure distribution. Liebeck pressure distr...

This paper examines the viability of using the combination of the vortex lattice method for aerodynamic performance prediction with a genetic algorithm for the optimization of the aerodynamic performance of horizontal axis wind turbine blades. The work described in this paper includes the adaptation of a vortex lattice code designed to predict propeller performance to wind turbine performance p...

3. Applicable Pollutants: Submicron Particulate Matter (PM) greater than or equal to 0.3 micrometer (μm) in aerodynamic diameter, and PM greater than or equal to 0.12 μm in aerodynamic diameter that is chemically, biologically, or radioactively toxic; hazardous air pollutants (HAPs) that are in particulate form, such as most metals (mercury is the notable exception, as a significant portion of ...