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Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
N. García-Polanco Área de Mecánica de Fluidos and LITEC, CSIC-Universidad de Zaragoza, C/María de Luna 3, 50018 Zaragoza, Spain. E-mail: [email protected]
J. Palencia Universidad Simón Bolívar, Dpto. de Conversión de Energía. AP 89000,Caracas, Venezuela. E-mail: [email protected]
2011-01-2626
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� INDEX
• Introduction
• Design Process
• Experimental Methodology
• Wind Tunnel Facilities
• Aerodynamic Propeller Study
• Experimental Test
• Results
• Conclusions
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
2011-01-2626
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� INTRODUCTION
� The present research is due to study the performance of engine-propeller cells to be used in the design of a Micro Air Vehicle (MAV).
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
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� INTRODUCTION(2)
• Engine: is a two strokes internal combustion engine (ICE),COX Pee Wee 0.327 cm3 (0.02 in3), without muffler and dimensions: 5 x 1.8 x 5 (cm).
• Propellers: A) Thimble Drome©. Dimensions: 11.43cm (diameter) x 5.08cm (pitch). B) APC©. Dimensions: 10.66cm (diameter) x 10.16cm (pitch).
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
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� DESIGN PROCESS
• Design conditions: weigh less than 200gr, maximum measurement of 30cm, to fly a distance of 200m, and to be able to carry a camera and chemical sensors.
• One of the goals of the study is to use commercial parts (engines and propellers) in order to reduce manufacturing cost.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
2011-01-2626
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� EXPERIMENTAL METHODOLOGY
• An experimental methodology was used to measure the followings variables for the engine-propeller cell: Thrust (T), velocity (RPM), cylinder head temperature (CHT), wind incident velocity (V∞), aerodynamic drag (D), torque (Q) and velocity profile behind every propeller.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
2011-01-2626
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� WIND TUNNEL FACILITIES
• The experiments are made in a subsonic open-circuit wind tunnel with a maximum flow velocity of 35 m/s with a test section size 0.45m x 0.45m x 1.20m.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
2011-01-2626
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� AERODYNAMIC PROPELLER STUDY• Axial component of the velocity V∞ due to the movement of the plane.
• Tangential component caused by the propeller rotation.• Velocity Profile behind the propeller (V∞ =6.26m/s, measurement in two points from X direction).
• Measurement of Incidence Angle along the blade.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
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� EXPERIMENTAL TESTS
• Aerodynamic Drag Coefficient of the propeller-enginecell (engine off), for each propeller.
• Static Thrust: test realized with engine on and tunnel off, at different RPM.
• Dynamic Thrust: test with engine and tunnel on, atdifferent RPM and different tunnel flow velocity.
• Velocity profile behind every propeller.
• Engine-torque: out of the tunnel and with a special testbench for different angular speed.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
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� RESULTS(1)• Aerodynamic Drag Coefficient of the propeller-engine cell (engine off), for each propeller.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
2011-01-2626
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� RESULTS(2)• Static Thrust: test realized with engine on and tunnel off, atdifferent RPM.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
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� RESULTS(3)• Dynamic Thrust: test with engine and tunnel on, at different
RPM and different tunnel flow velocity.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
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� RESULTS(4)• Dynamic thrust and drag vs wind tunnel flow velocity for
propeller B.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
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� RESULTS(5)• Velocity profile
downstream thepropeller and Incidence angle.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
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� RESULTS(6)• Engine-torque: out of the tunnel and with a special test
bench for different angular speed.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
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� CONCLUSIONS
• Propeller B generates a greater load on the engine than propeller A, demonstrated by an increase in temperature CHT.
• For this engine-propeller cell, is recommended to operate the airplane in a range from 7 to 13 m/s.
• The shape of the velocity profile verified the lost effect of blade tip vortex flow being in propeller B at final 10% of the radius. And generate useful information to simulate the velocity profile behind the propeller with CDF.
• Propeller B was more efficient than propeller A.
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
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� Thanks…
• QUESTIONS?
Aerodynamic Design of a Micro Air Vehicle: Study of Propeller-Engine Performance
2011-01-2626
