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Showing 1 to 15 of 15 for “"thrust coefficient"”.
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The use of foil generated vorticity as a hover actuator system for undersea vehicles
… for two types of motion. Using the time-averaged thrust coefficient, I find that the lower frequencies provide the highest thrust coefficient of 3.1 at G0=600, hdc= 1.5, and f=0.4Hz for the treading water mode. Significantly lower thrust coefficients are observed for the figure eight mode with …
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Flapping motion of a three-dimensional foil for propulsion and maneuvering of underwater vehicles
… two-axis control. Tests to determine the mean thrust coefficient of the foil were conducted over a wide parametric space. This parameter space included two roll amplitudes, with induced heave (at the 0.7 span) to chord ratio of hO.7 / c = 1.00 and 1.50; respectively, with Strouhal numbers …
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Hydrodynamic performance and vortex shedding of a biologically inspired three-dimensional flapping foil
… motion are investigated. The mean planform area thrust coefficient and efficiency are recorded over a paramtetric space that included three roll amplitudes, with induced heave (at 0.7 span) to chord ratio, ḣ₀.₇ / c = 1.0, 1.5 and 2.0; Strouhal numbers ranging from 0.2 to 0.6 and maximum angle …
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Estudo experimental de uma família de rotores tipo hélice
The Power Coefficient, Torque Coefficient and Thrust Coefficient was derived from the data collected using 20 models of 3 blades propeller wind rotors tested in a wind tunnel. The rotor analysed had untwisted blades of constant chord and the sarne profile – Go 624. The models used had a 0,45m …
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Analysis of fountain effect for tiltrotor configuration using computational fluid simulation and experimental method
… wind tunnel tests performed indicated that lift coefficients of the wind tunnel tests and CFD results closely replicate each other’s results for crosswind angles lower than 60°. Therefore, it can be stated that the URANS-based CFD methodology can simulate the tiltrotor’s wing/rotor configuration …
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Hydrodynamic effects of leading-edge tubercles on control surfaces and in flapping foil propulsion
… used on a flapping foil for the first time. Mean thrust coefficient, CT , power coefficient, CP , and efficiency, n, were measured over a wide parametric space. The maximum thrust coefficient and efficiency measured using the smooth control foil were CT = 3.511 and n = 0.678. The maxima using the …
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Wind plant annual energy production maximisation and efficiency improvement with considerations for thrust and turbulence intensity
… increase in turbine-level turbulence intensity, thrust coefficient, and thrust as consequences imposed by the unconstrained optimisation-enhanced power increments. These observations have not been previously highlighted nor addressed in the literature of WP power optimisation. In addition to …
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Propulsion performance of a microcavity discharge device
… device modified for use as an electrothermal thruster, called a MCD thruster. Development of the MCD thruster was primarily experimental in nature, although computational modeling provided validation and suggested future development paths. Three types of tests were performed to validate the …
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Propulsion system analysis for conceptual design: drag and losses of nozzles and mixed compression inlets
… geometries are considered, as are non thrust-vectoring nozzles. Only the internal losses of these nozzles are considered, and these losses are characterized by the thrust coefficient. The results of this survey have also been added to ACSYNT to extend the thrust prediction capabilities …
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From Oscillating Flat Plate to Maneuvering Bat Flight – Role of Kinematics, Aerodynamics, and Inertia
… (LEVs) are found to be responsible for producing thrust while Trailing Edge Vortices (TEVs) produce drag. The vortex dynamics becomes nonlinear for higher kh and three main vortex-vortex interactions (VVI) are identified in the flow-field. To estimate the sole effect of LEVs on thrust coefficient, …
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Analysis of mixing and thrust diagnostics for shock tunnel hot nozzle testing
… presents the design and assessment of mixing and thrust measurement systems for use with a shock tunnel for these applications. Results from preliminary testing of focused-Schlieren, shearing interferometer, and Mie-scattering systems are presented. The Mie-scattering method was judged to be most …
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A model-following digital control law for an EBF-STOL aircraft
… with step inputs to the elevator and thrust coefficient. Results are also presented for a filtered gaussian input to each of these control variables.
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Experimental investigation of microfabricated bipropellant rocket engines
… satellites, launch systems and attitude control thrusters of reduced mass will be required. Microrocket engines could provide a low mass, high specific impulse, modular answer to these needs. These small rocket engines would produce thrust of order of 10's of Newtons at a thrust-to-weight of over …
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A numerical study of surface air temperature response to vertical mixing and momentum extraction by wind farms and the impacts of wind farms on mesoscale boundaries
… west central Texas to changes in the turbines’ thrust and TKE coefficients during meteorological summers. A control run with no wind turbines is compared to three experimental tests, each with differing thrust and TKE coefficients. The experimental tests are fist compared to observed data from …
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Effect of turbine motion on floating off shore wind turbine aerodynamics
… LES parameters such as the tip-speed ratio and thrust coefficient, along with validation with the development of an analytical model that can capture the observed frequency dependence. Finally, future work should also further hone in on the inclusion of LES at different freestream wind and surge …