Session: 08-08-05 Renewable Energy V and Sustainable and Grid-Interactive Buildings

Paper Number: 73558

Start Time: Friday, 01:55 PM

73558 - Design of a Horizontal Axis Wind Turbine for a Venusian Environment 

The atmosphere of Venus is 96% carbon dioxide and contains clouds of sulfur dioxide and sulfuric acid, with surface temperatures in excess of 470 degrees Celsius and pressures 92 times that of Earth. These extreme environmental conditions make planetary exploration difficult as modern electronics cannot survive for prolonged periods of time. Photovoltaics, a conventional power generation method for Mars rovers, are inefficient on the planet’s surface due to the dense cloud cover and harsh environment. The NASA – JPL Hybrid Automaton Rover Venus proposes using a mechanical wind energy harvester to further explore the Venusian surface. At the proposed landing site, the surface wind speeds range from 0.3 to 1.3 m/s with an average wind speed of 0.6 m/s. These wind speeds, combined with the high density of Venusian air, results in promising potential for power generation. The power goal for the proposed wind harvester is 9W at the average wind speed of 0.6 m/s. A horizontal axis turbine is used to avoid dynamic stall experienced by vertical axis wind turbines at low wind speeds. 

In the horizontal axis wind turbine design, existing airfoil profiles were evaluated and chosen using QBlade. The blade designs were analyzed using blade element momentum theory (BEM) and computational fluid dynamics (CFD) to predict and improve turbine performance. Small-scale wind turbines were 3D printed, post-processed, and tested in a subsonic wind tunnel. Wind tunnel testing was performed to test the validity of our design tools. Subsequent testing was performed in water, as the greater fluid density allowed for testing at lower speeds to better simulate Venus surface conditions.  

The preliminary water testing was carried out to characterize turbine performance. In this process, a 3D printed 1:4 scale turbine was placed in an open-channel pool with flow supplied through a pump. The turbine was a fixed 2.33 m distance away from the inlet of the flow. The flow speed, turbine rotational speed, and torque produced were recorded. The results yielded turbine efficiencies between 7.7% and 53.9% in the range of tip speed ratios (TSR) tested. These results exceeded design expectations, at the designed TSR, where an efficiency of 40% was to be expected.  

Based on the preliminary results, modifications are being made to the water testbed to improve the testing process as well as more accurately simulate conditions on the surface of Venus. The collected data and the aforementioned design tools are used to improve the current turbine design. 

Presenting Author: Zacharias Garza California State University, Los Angeles

Authors:

Zacharias Garza California State University, Los Angeles
Kevin Pan California State University of Los Angeles
Anthony Izaguirre California State University, Los Angeles
Saul Loza California State University, Los Angeles
Jonathan Serrano California State University, Los Angeles
Oscar Lopez California State University, Los Angeles
Jim Kuo California State University, Los Angeles
Jonathan Sauder Jet Propulsion Laboratory