aerodynamic design of a micro air vehicle: study of propeller-engine performance sae2011 01-2626
DESCRIPTION
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). Design conditions: weigh less than 200gr, maximum size 30cm, to fly a distance of 200m, and 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. 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 (VD), aerodynamic drag (D), torque (Q) and velocity profile behind every propeller. Results: aerodynamic Drag Coefficient of the propeller-engine cell (engine off), for each propeller. Dynamic Thrust: test with engine and tunnel on, at different RPM and different tunnel flow velocity.TRANSCRIPT
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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
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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
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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
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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
2011-01-2626
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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
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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