표제지
요약문
Abstract
목차
기호 설명 9
Ⅰ. 서론 15
1. 연구 배경 및 목적 15
2. 연구 방법 17
Ⅱ. 본론 18
1. 인공지능 설계 익형과 유인드론용 프로펠러 18
1.1. 인공지능 이론 18
1.2. 익형이론 20
1.3. 양력계수와 항력계수 22
1.4. 프로펠러 이론 23
1.5. 프로펠러 소음 이론 29
2. 유인드론용 인공지능 설계 프로펠러의 설계, 해석, 시험 40
2.1. 프로펠러 설계 41
2.2. 프로펠러 유동해석 48
2.3. 프로펠러 시험 52
3. 유인드론용 인공지능 설계 프로펠러의 해석 및 시험 결과 55
3.1. 해석기법 검증 55
3.2. 프로펠러 유동해석 결과 71
3.3. 프로펠러 성능시험 결과 78
3.4. 프로펠러 소음해석 결과 80
3.5. 프로펠러 소음시험 결과 85
Ⅲ. 결론 91
참고문헌 93
Table. 1. A-Weighting Table 39
Table. 2. Loss-rates according to network architecture 42
Table. 3. Loss-rates according to network architecture 42
Table. 4. Comparison of input and output of learning models 42
Table. 5. Inverse design output comparison by using Moin's model 42
Table. 6. Axial fan CFD data (t=0s) 64
Table. 7. Leq comparison between measurement and simulation[이미지참조] 70
Table. 8. Propeller CFD data (t=0s) 82
Table. 9. Comparison of Leq between simulation and experiment (a)Position 1[이미지참조] 89
Table. 9. Comparison of Leq between simulation and experiment (b)Position 2[이미지참조] 89
Table. 9. Comparison of Leq between simulation and experiment (c)Position 3[이미지참조] 89
Table. 10. Ground noise at 10m in the air 90
Fig. 1. Schematic of DNN architecture 19
Fig. 2. Schematic of activate function 19
Fig. 3. Schematic of airfoil geometry 21
Fig. 4. Schematics of blade element ((a) Blade element, (b) Aerodynamic force) 24
Fig. 5. Schematic of actuator disk model in uniform flow 25
Fig. 6. Schematic of blade section with velocity triangle 28
Fig. 7. 1-D Harmonic wave propagation 30
Fig. 8. Schematic of retarded time 36
Fig. 9. Schematic of AI design process 40
Fig. 10. The RMSE of the sum of the lift and drag errors 43
Fig. 11. Airfoil section comparison 44
Fig. 12. Ratio of maximum thickness to chord in terms of non-dimensional radius 45
Fig. 13. Blade section of AI-designed propeller (Chord) 45
Fig. 14. Blade section of AI-designed propeller (Twist angle) 46
Fig. 15. Top view of Eagle bio-mimetic and AI-design propellers 47
Fig. 16. Side view of Eagle bio-mimetic and AI-design propellers 47
Fig. 17. Schematics of computational domain 49
Fig. 18. Generated mesh configuration ((a) Domain mesh (b) Propeller mesh) 51
Fig. 19. Mesh size to chord by radius 51
Fig. 20. Schematic of propeller thrust test stand 52
Fig. 21. Acoustic testing stand 53
Fig. 22. Schematic of acoustic testing stand (Side view) 54
Fig. 23. Schematic of acoustic testing stand (Top view) 54
Fig. 24. Schematic of computational domain 55
Fig. 25. Schematic of computational domain mesh 57
Fig. 26. Schematic of computational rotate domain mesh 57
Fig. 27. Schematic of computational state domain mesh 57
Fig. 28. Schematic of computational domain 58
Fig. 29. Schematics of noise testing stand 59
Fig. 30. Photo of noise testing stand 60
Fig. 31. Relating percentage error of torque at each cycle (Axial fan) 61
Fig. 32. Performance curve at each volume flow rate 61
Fig. 33. Velocity distribution of Axial fan 62
Fig. 34. Pressure time-derivative at fan outlet 62
Fig. 35. Q-criterion distribution around the fan 63
Fig. 36. SPL in the calculated receiver 65
Fig. 37. SPL measured at 1200RPM 66
Fig. 38. SPL measured at 2000RPM 67
Fig. 39. SPL measured at 2565RPM 67
Fig. 40. SPL measured at 3385RPM 68
Fig. 41. SPL measured at 3981RPM 68
Fig. 42. SPL measured at 4750RPM 69
Fig. 43. Comparison between measurement and simulation 70
Fig. 44. Average torque comparison per each cycle 71
Fig. 45. Relative percentage error of torque at each cycle 72
Fig. 46. Torque variation at azimuthal angles during a single rotation for both propellers of diameter 1.5 m 73
Fig. 47. Thrust variation at azimuthal angles during a single rotation for both propellers of diameter 1.5 m 73
Fig. 48. Velocity distribution of propeller (a) Eagle bio-mimetic 74
Fig. 48. Velocity distribution of propeller (b) AI-designed 74
Fig. 49. Pressure time-derivative at domain (a) Eagle bio-mimetic 75
Fig. 49. Pressure time-derivative at domain (b) AI-designed 75
Fig. 50. Q-criterion distribution around the propeller (a) Eagle bio-mimetic 76
Fig. 50. Q-criterion distribution around the propeller (b) AI-designed 76
Fig. 51. Photo of fabricated propellers (Top: Eagle bio-mimetic, Bottom: AI-design) 77
Fig. 52. Thrust testing stand for counter-rotating propellers 78
Fig. 53. Non-dimensional coefficients of CT/CP at several rotational speeds for both proto-type propellers[이미지참조] 79
Fig. 54. Turbulent Energy Spectrum 80
Fig. 55. Cut-off frequency of all cells making up the propeller surface (AI-designed propeller, 1000RPM) 81
Fig. 56. CAA calculation SPL for both propellers (a)Position 1 82
Fig. 56. CAA calculation SPL for both propellers (b)Position 2 83
Fig. 56. CAA calculation SPL for both propellers (c)Position 3 83
Fig. 57. SPL measured at 750RPM for both propellers (a)Position 1 85
Fig. 57. SPL measured at 750RPM for both propellers (b)Position 2 86
Fig. 57. SPL measured at 750RPM for both propellers (c)Position 3 86
Fig. 58. SPL measured at 1000RPM for both propellers (a)Position 1 87
Fig. 58. SPL measured at 1000RPM for both propellers (b)Position 2 87
Fig. 58. SPL measured at 1000RPM for both propellers (c)Position 3 88