APPENDIX B The additional Vortex - X flow visualizations can be found in Appendix B.
Figure B1 . Two - rotor cases at forward flight 20 ft/s in wind t unnel with pitch - 10 degrees.
Figure B3 . Four - rotor cases at forward flight 20 ft/s Figure B2 . Flow visualization of rotors numbers 1 - 4 in in wind tun nel - side view - pitch angle (a) - 10 degrees (b) the short rotor configuration, at the - 10 degrees pitch - 5 degrees ( c) 0 degrees.
angle, and with a wind tunnel speed of 20 ft/s.
APPENDIX C APPENDIX D
APPENDIX C APPENDIX D The summation of the experimental and CHARM predictions The additiona l figures for power versus r evolution power at the pitch angle of - 10, - 5, and 0 degrees are presented number s are presented in Appendix D . The figure shows in Appendix C .
the power values for the last ten revolutions.
Table C1 . The summation of power CHARM prediction and experimental data for two MTB rotors at the wind tunnel in forward flight testing at speed of 20ft/s.
V [ft/s] Pitch [Deg] Data, ∑ P[W] CHARM, ∑ P[W] 20.10 - 10 179.62 183.44 - 5 172.86 170.02 19.96 19.82 0 171.67 182.70 Table C2 . The summation of power for CHARM prediction and experimental data for four MTB rotors at the wind tunnel in forward flight speed of 20ft/s.
V [ft/ s] Pitch [Deg] Data, ∑ P[W] CHARM, ∑ P[W] 20.30 - 10 354.42 348.99 20.42 - 5 347.54 351.97 20.44 0 339.54 373.60 Figure D1 . CHARM power variation over last 10 Table C3 . The average discrepancy of power between the rotor revolutions (total 50 revolutions) with wind CHARM prediction and experimental data for four tunnel walls: pitch angle of - 10 deg; 20 ft/s; four - rotor MTB rotors at the wind tunnel in forw ard flight testing case.
at speed of 20ft/s.
V [ft/s] Pitch [Deg] Power Ave. Discrepancy% 20.30 - 10 6.30 20.42 - 5 9.62 20.44 0 12.33 Table C4 . The average discrepancy of power between the CHARM prediction and experimental data for six MTB rotors at the Tall configuration at the wind tunnel in forward flight testing at speed of 20ft/s and 40 ft/s.
V [ft/s] Pitch [Deg] Power Ave. Discrepancy% 20.73 - 10 7.17 20.31 - 5 3.92 20.11 0 5.34 40.01 - 10 3.23 39.97 - 5 4.89 39.94 0 6.91 Figure D2 . CHARM power varia tion over last 10 rotor revolutions (total 50 revolutions) with wind tunnel walls: pitch angle of - 5 deg; 20 ft/s; four - rotor case.
ACKNOWLEDGMENTS The author would like to expr ess profound gratitude to Gloria Yamauchi, who guided her in all steps of this project, and Wayne Johnson, who gave so very generously of his knowledge and time. The author would like to thank Carl Russell, Christopher Silva, S arah Conley, Ethan Romander, Dan Wachspress, Thomas Norman, and Dorcas Kaweesa. The author would like to acknowledge William Warmbrodt for his continued support and Kristen Kallstrom, who developed the airfoil tables for the MTB rotors.
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