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hessflight

Boomerang Flight Dynamics

John C. Vassberg   wrote this paper whilst working as Chief Aerodynamicist of Boeing Research and Technology.  He presented it at the 30th AIAA Applied Aerodynamics Conference, New Orleans, Louisiana, 28 June, 2012.  

 

A quote form the absract: "Unsteady Reynolds-averaged Navier-Stokes solutions provide accurate aerodynamic characteristics of the subject boomerang. The high-fidelity aerodynamic model is coupled with the equations of motion to provide accurate six-degree-of-freedom simulations of boomerang flight dynamics. Boomerang orientation during its flight trajectory is described by the classical Euler angles."

 

Full PDF Here 

Images from the paper, showing how the Pressure coefficient on the top surface of the boomerang as it spins around moving right to left and spinning anti clockwise.  It shows how the lift will be greatest for the 'lifting arm' at the 'top' of its spin in positions 2 and 3 and the 'dingle' arm in position 6.  

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Vassberg developed his own equations for motion for the flight of the boomerang. Below is an excerpt from the paper

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Vassberg produced a single simulated flight path for the virtual boomerang thrown at a high angle above the horizon at 60 mph. The spin was faster than we normally achieve. Figure 42 from the paper shows the flight path modelled in 3 dimensions.  The boomerang was rather thick and heavy so it crashed to ground. The computational cost of working out all the pressure and airflows meant that only one simulation was done on one boomerang

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The virtual boomerang used in the study was rather thick.

CFD (computer fluid dynamics) was used to work  out how the aif flowed over it and caused pressure changes.

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