Applying Rotorcraft Modelling Technology to Renewable Energy Research

The perceived need to reduce mankind's impact on the global climate motivates towards a future society in which a significant proportion of its energy needs will be extracted from the winds and the tides of the planet. This paper shows several examples of the application of Brown's Vorticity Transport Model, originally developed to perform simulations of helicopter aeromechanics and wake dynamics, to the analysis of the performance of renewable energy devices and their possible impact on the environment. Prediction of the loading on wind turbines introduces significant additional challenges to such a model, including the need to account fully for the effects of radial flow on blade stall. The wake-mediated aerodynamic interactions that occur within a wind farm can reduce its power output significantly, but this problem is very similar to that where the aerodynamic unsteadiness of the coupled wake of the main and tail rotors of a helicopter can result in significantly increased pilot workload. The helicopter-related problem of brownout, encountered during operations in desert conditions, has its analogue in the entrainment of sediment into the wakes of tidal turbines. In both cases it may be possible to ameliorate the influence of the rotor on its environment by careful and well-informed design. Finally, calculations of the distortion and dispersal of the exhaust plumes of a helicopter by the wake of its rotor allow insight into how wind turbines might interfere with the dispersal of pollutants from nearby industrial sites. These examples show how cross-disciplinary information transfer between the rotorcraft field and the renewable energy community is helping to develop the technologies that will be required by our future society, as well as helping to understand the environmental issues that might need to be faced as these technologies become more prevalent.

[1]  Richard E. Brown,et al.  The effect of blade aerodynamic modelling on the prediction of high-frequency rotor airloads , 2009 .

[2]  Adam R. Kenyon,et al.  Wake dynamics and rotor-fuselage aerodynamic interactions , 2007 .

[3]  R. E. Brown,et al.  Modeling the Mutual Distortions of Interacting Helicopter and Aircraft Wakes , 2003 .

[4]  Green,et al.  Measurements of a Rotor Flow in Ground Effect and Visualisation of the Brown-out Phenomenon , 2008 .

[5]  Richard E. Brown,et al.  Simulating the aerodynamic performance and wake dynamics of a vertical‐axis wind turbine , 2011 .

[6]  F. Coton,et al.  A study on rotational effects and different stall delay models using a prescribed wake vortex scheme and NREL phase VI experiment data , 2008 .

[7]  Eleuterio F. Toro,et al.  A weighted average flux method for hyperbolic conservation laws , 1989, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[8]  Markus Raffel,et al.  The HART II Test in the LLF of the DNW - a Major Step towards Rotor Wake Understanding , 2002 .

[9]  Eric A. Gillies,et al.  The flow field around a rotor in axial descent , 2005, Journal of Fluid Mechanics.

[10]  J. Gordon Leishman,et al.  Fluid Dynamics of Interacting Blade Tip Vortices With a Ground Plane , 2010 .

[11]  Richard E. Brown,et al.  Wake structure and kinematics in the vortex ring state , 2009 .

[12]  Richard E. Brown.  Simulating Wind Turbine Interactions using the Vorticity Transport Model , 2009 .

[13]  D. M. Somers,et al.  Design and experimental results for the S809 airfoil , 1997 .

[14]  Richard E. Brown,et al.  Efficient High-Resolution Wake Modeling Using the Vorticity Transport Equation , 2004 .

[15]  Timothy M. Fletcher,et al.  Main rotor - tail rotor interaction and its implications for helicopter directional control , 2008 .

[16]  Richard E. Brown,et al.  Interactional aerodynamics and acoustics of a hingeless coaxial helicopter with an auxiliary propeller in forward flight , 2008 .

[17]  Catriona Phillips,et al.  Eulerian Simulation of the Fluid Dynamics of Helicopter Brownout , 2009 .

[18]  Maureen Hand,et al.  Unsteady Aerodynamics Experiment Phase VI: Wind Tunnel Test Con gurations and Available Data Campaigns , 2001 .

[19]  Niels N. Sørensen,et al.  Navier-Stokes predictions of the NREL phase VI rotor in the NASA Ames 80-by-120 wind tunnel , 2002 .

[20]  Richard E. Brown,et al.  The effect of blade aerodynamic modelling on the prediction of the blade airloads and the acoustic signature of the HART II rotor , 2009 .

[21]  Richard E. Brown,et al.  Predicting wind turbine blade loads using vorticity transport and RANS methodologies , 2009 .

[22]  Richard E. Brown,et al.  Rotor Wake Modeling for Flight Dynamic Simulation of Helicopters , 2000 .

[23]  Leishman,et al.  Investigation of Sediment Entrainment in Brownout Using High-Speed Particle Image Velocimetry , 2009 .

[24]  Hyo Won Kim.  Interactional Aerodynamics and Acoustics of a Hingeless Coaxial Helicopter with an Auxiliary Propeller in Forward Flight , 2008 .

[25]  Hyo Won Kim,et al.  The effect of rotor design on the fluid dynamics of helicopter brownout , 2009 .

[26]  H. W. Kim,et al.  Coaxial Rotor Performance and Wake Dyanmics in Steady and Manoeuvring Flight , 2006 .