1. Rocket Lab KAIST H 2 O 2 - 케로신 로켓을 초기 가속장치로 갖는 새로운 램젯 추진기관 박 근 홍 국방과학연구소 대함유도무기체계개발단

2. 2/68 Rocket Lab KAIST Contents Interim Report Summary Introduction - Background - Novel concept - Objectives Experimental Setup - Experimental apparatus - Gas generator - Combustor Results and Discussion - Various initial combustor temp. & pressure - Various F/O ratio Conclusion

3. 3/68 Rocket Lab KAIST Interim Report Summary

4. 4/68 Rocket Lab KAIST Reusable Single Stage To Orbit (SSTO) aerospace planes by NASA, JAXA, etc. To orbital trajectory without dropping off any hardware The goal of fully reusable SSTO - Lower operating costs - Improved safety - Better reliability than current launch vehicles Single Stage To Orbit (SSTO)

5. 5/68 Rocket Lab KAIST Operating condition of RBCC RBCC engine combines rocket and air-breathing propulsion system Ejector-jet mode Ramjet mode Scramjet mode Rocket mode Rocket Based Combined Cycle engine (RBCC)

6. 6/68 Rocket Lab KAIST Central & annular injection - Annular bell type provides rapid mixing of the streams Working principle of ejector-jet

7. 7/68 Rocket Lab KAIST Boundary conditions Ejector-jet modeling

8. 8/68 Rocket Lab KAIST AR=2.17, L/D=3.41, Primary P=17atm Mach contour

9. 9/68 Rocket Lab KAIST AR=3.18, L/D=3.41, Primary P=17atm

10. 10/68 Rocket Lab KAIST Data comparison (AR=2.17) kw-sst ke st. Wall pressure distribution

11. 11/68 Rocket Lab KAIST Data comparison (AR=3.18)

12. 12/68 Rocket Lab KAIST Over 10.23 L/D - AR=2.17 : Thrust ratio approach 1.8 - AR=3.18 : Thrust ratio decreases finally Ejector-jet thrust ratio

13. 13/68 Rocket Lab KAIST Performance curves At same AR, performance curves have same slopes for various L/D - The secondary inlet mass flow rate maintains same value with respect to increase of L/D. - Thrust ratio increasing factor is not suction performance increase but mixing performance increase

14. 14/68 Rocket Lab KAIST - The tests of an axi-symmetric annular bell type ejector-jet were conducted to investigate the thrust performance of ejector-jet - Thrust increased with increase of L/D (3.41 to 10.23) AR=2.17 : 33% increased AR=3.18 : 26% increased - Thrust ratio increasing factor is not suction performance but mixing performance - It is expected that thrust maximization method will be helpful to a variety of ejector-jet applications Summary

15. 15/68 Rocket Lab KAIST Introduction

16. 16/68 Rocket Lab KAIST Introduction In the atmosphere, RBCC engine and air-breathing propulsion system get more specific impulse (Isp) than rocket-only system Air-breathing propulsion system produces little or no thrust during takeoff, a rocket engine or its equivalent must be part of the vehicle. H 2 O 2 gas generator as a oxidizer of bipropellant rocket for launch stage of air-breathing propulsion system

17. 17/68 Rocket Lab KAIST Demand of green propellant Low toxicity and ecologically friendly propellants are in demand for post cold war Hydrogen peroxide is one of rare non-toxic storable propellants Comparing with 100% oxygen LOX, obtainable Isp of Hydrogen peroxide is about only 10% less than LOX

18. 18/68 Rocket Lab KAIST Decomposition of H 2 O 2 Exothermic reaction 2H 2 O 2 ( ℓ ) → 2H 2 O( g ) + O 2 ( g ) + Heat - 2884.47kJ/kg heat produced - H 2 O 2 has been used to many application field

19. 19/68 Rocket Lab KAIST History about H 2 O 2 for oxidizer Concentrated hydrogen peroxide and hydrazine hydrate solution in methyl alcohol

20. 20/68 Rocket Lab KAIST Relative works Purdue university, USA - Decomposed H 2 O 2 /JP-8 auto-ignition test in dump combustor - Application to liquid bipropellant rocket

21. 21/68 Rocket Lab KAIST Tokai university, Japan Hybrid/liquid rocket engine - Decomposed H 2 O 2 is Oxidizer for rocket engine - Ignition by spark plug

22. 22/68 Rocket Lab KAIST Novel concept ramjet

23. 23/68 Rocket Lab KAIST Integral Rocket Ramjet (IRR) Booster-Ramjet transition of IRR

24. 24/68 Rocket Lab KAIST Novel concept propulsion system H 2 O 2 rocket mode - Inlet closed, H 2 O 2 Gas generator produces thrust and kerosene injects to decomposed hot jet Transition mode - H 2 O 2 gas generator reduces decomposed jet and free stream entrained Ramjet mode - If sufficient ram pressure attained, Ramjet mode operates

25. 25/68 Rocket Lab KAIST Objectives Auto-ignition test of H 2 O 2 decomposed jet and Kerosene Investigation of ignition and combustion characteristics - Various initial combustor temp. and pressure - Various Fuel-Oxygen ratio Ascertainment of the possibility of novel concept using H 2 O 2 – Kerosene rocket for launch stage of ramjet

26. 26/68 Rocket Lab KAIST Experimental setup

27. 27/68 Rocket Lab KAIST Experimental system - Kerosene & H 2 O 2 supplied to catalytic bed & combustor by pressurized nitrogen gas - Pressure & temp. measured at catalytic bed & combustor - Check valve installed at fuel injector line - All pneumatic valve were remote controlled

28. 28/68 Rocket Lab KAIST Test Stand Combustor attached to H 2 O 2 test facility

29. 29/68 Rocket Lab KAIST Kerosene Experimental kerosene - General jet fuel ‘Jet A-1’ used JET A-1 Flash point38 °C Autoignition temperature:210 °C Freezing point:−47 °C (−40 °C for JET A) Open air burning temperatures:260–315 °C (500–599 °F) Maximum burning temperature:980 °C (1796 °F) Density at 15 °C (60 °F):0.775–0.840 kg/L Chemical Compound:C 12 H 23

30. 30/68 Rocket Lab KAIST Experimental H 2 O 2 - Rocket grade 90%, 95% concentration used Hydrogen peroxide Concentration(%) 1009895908580 Density(kg/ ㎥ ) at 25 ℃ 14591431.9-1386.4-- Adiabatic Decomp. Temp.( ℃ ) 995945871749626503 Specific heat ratio1.2491.2521.2561.2651.2761.288 C* velocity (m/sec)1,0351,016987936881821

31. 31/68 Rocket Lab KAIST Propellants storage Kerosene storage tank(1ℓ, 25 bar), Hydrogen peroxide storage tank(1ℓ, 35 bar)

32. 32/68 Rocket Lab KAIST H 2 O 2 gas generator Dual catalytic bed system - Platinum was selected as the catalyst for fore part of the bed and LSC(La 0.8 Sr 0.2 CoO 3 ) was selected for aft bed - Non-preheating and relatively high C* efficiency capability

33. 33/68 Rocket Lab KAIST Gas generator system Real picture of platinum, LSC catalytic bed and gas generator

34. 34/68 Rocket Lab KAIST Combustor Schematic of experimental combustor

35. 35/68 Rocket Lab KAIST Combustor configuration Cross sectional view combustor configuration (unit:mm) CLCL 125CTCT 15 CDCD 25CICI 1.7 CECE 4, 5, 7TITI 30 T L, K L 12.5PLPL 22.5

36. 36/68 Rocket Lab KAIST Experimental combustor Combustor with C-D nozzle

37. 37/68 Rocket Lab KAIST Fuel injector Spay injector test - Spay particle diameter 100~150μm

38. 38/68 Rocket Lab KAIST Kerosene mass flow rate Kerosene mass flow rate was computed like below - CdA value attained from spray injector test CdA ≒ 5.75xE-8 m 2, ρ ≒ 810kg/m 3 - Delta P from measured kerosene tank pressure and combustor pressure

39. 39/68 Rocket Lab KAIST Oxygen mass flow rate We assumed H 2 O 2 decomposed completely by thermal and surface reaction. - 95% H 2 O 2 → 3.35g/s, 90% H 2 O 2 → 3.05g/s

40. 40/68 Rocket Lab KAIST Experiment parameters Various initial combustor temp. and pressure Case 1Case 2Case 3 Throat dia.5 mm4 mm7 mm Initial pressure3.2 bar4.8 bar1.7 bar Initial temperaturevariation Over 400 ℃ F/O ratiovariation

41. 41/68 Rocket Lab KAIST Results and discussion 95% hydrogen peroxide w/ 5mm diameter nozzle

42. 42/68 Rocket Lab KAIST Temperature history F/O=0.31 case - Tc maintains over 700°C - Temperatures in combustor increase along the time - Fuel injected when combustor temp. about 500°C - Failure of ignition

43. 43/68 Rocket Lab KAIST F/O=0.45 Reaction detected aft combustor - After fuel injection, T3,4 increase and combustor pressure increase slightly - Reaction aft combustor but failure of ignition

44. 44/68 Rocket Lab KAIST F/O=0.59 Reaction detected aft combustor - After fuel injection, T1,2 decrease while T3,4 increase slightly increase and combustor pressure increase - Reaction aft combustor but failure of ignition

45. 45/68 Rocket Lab KAIST Results and discussion 90% hydrogen peroxide w/ 5mm diameter nozzle

46. 46/68 Rocket Lab KAIST F/O=0.64 Ignition & combustion detected - Tc maintains over 650°C - Lower temp. comparing former cases - Auto ignition @ T4 is about 420°C - Stable combustion flame detected

47. 47/68 Rocket Lab KAIST F/O=0.82 Auto ignition and stable combustion - After ignition pressure abruptly increase 2 times and maintains stability - Temperature increase over 1000°C (Ignition temperature is about 420°C)

48. 48/68 Rocket Lab KAIST Temperature limit of auto ignition F/O=0.82 w/ about 355°C combustor temperature - Fuel injected about 355°C combustor temperature - After fuel injection, combustor temperature decreases - Failure of ignition

49. 49/68 Rocket Lab KAIST F/O=0.82 About 375°C combustor temperature - Fuel injected about 375°C combustor temperature - After fuel injection, combustor temperature decreases - Failure of ignition

50. 50/68 Rocket Lab KAIST Auto ignition at 395°C About 395°C combustor temperature - After ignition pressure abruptly increase 2 times and maintains stability - Temperature increase over 1000°C (Ignition temperature is about 395°C)

51. 51/68 Rocket Lab KAIST F/O ratio limit of auto ignition F/O=0.90 case - Fuel injected over 400°C combustor temperature - Auto ignition and stable combustion

52. 52/68 Rocket Lab KAIST F/O=1.00 case Failure of ignition - After fuel injection, T4 decrease and combustor pressure increase slightly - Reaction aft combustor but failure of ignition

53. 53/68 Rocket Lab KAIST Verification of ignition and combustion Direct image of ignition and combustion test - 90% hydrogen peroxide w/ initial pressure 3.2 bar, temperature 420°C, F/O=0.82

54. 54/68 Rocket Lab KAIST Results and discussion 90% hydrogen peroxide w/ 4mm diameter nozzle

55. 55/68 Rocket Lab KAIST Experiment parameters Various initial combustor temp. and pressure Case 1Case 2Case 3 Throat dia.5 mm4 mm7 mm Initial pressure3.2 bar4.8 bar1.7 bar Initial temperaturevariation Over 400 ℃ F/O ratiovariation

56. 56/68 Rocket Lab KAIST F/O=0.44 Ignition & combustion detected - After fuel injection, T4 and combustor pressure increase - At this case, kerosene storage tank pressure was about 7.5 bar - Auto ignition and combustion

57. 57/68 Rocket Lab KAIST F/O=0.56 Ignition & combustion detected - After fuel injection, T4 and combustor pressure increase - At this case, kerosene storage tank pressure was about 10 bar

58. 58/68 Rocket Lab KAIST F/O=0.82 Auto ignition and stable combustion - After fuel injection, T4 and combustor pressure increase - At this case, kerosene storage tank pressure was about 16 bar

59. 59/68 Rocket Lab KAIST F/O ratio limit of auto ignition F/O=0.96 case - Fuel injected over 400°C combustor temperature - Auto ignition and stable combustion

60. 60/68 Rocket Lab KAIST F/O=1.04 Failure of ignition - After fuel injection, T4 decrease and combustor pressure increase slightly - Reaction aft combustor but failure of ignition

61. 61/68 Rocket Lab KAIST Verification of ignition and combustion Direct image of ignition and combustion test - 90% hydrogen peroxide w/ initial pressure 4.8 bar, temperature 410°C

62. 62/68 Rocket Lab KAIST Results and discussion 90% hydrogen peroxide w/ 7mm diameter nozzle

63. 63/68 Rocket Lab KAIST Experiment parameters Various initial combustor temp. and pressure Case 1Case 2Case 3 Throat dia.5 mm4 mm7 mm Initial pressure3.2 bar4.8 bar1.7 bar Initial temperaturevariation Over 400 ℃ F/O ratiovariation

64. 64/68 Rocket Lab KAIST F/O=0.74 Failure of ignition - After fuel injection, T4 and combustor pressure shows no movement - There is no reaction after fuel injection

65. 65/68 Rocket Lab KAIST F/O=0.95 Failure of ignition - After fuel injection, T4 decrease and combustor pressure increase slightly - Reaction aft combustor but failure of ignition

66. 66/68 Rocket Lab KAIST F/O=1.03 Failure of ignition - After fuel injection, T4 decrease and combustor pressure increase slightly - Reaction aft combustor but failure of ignition

67. 67/68 Rocket Lab KAIST Conclusion

68. 68/68 Rocket Lab KAIST Conclusion Conceptual study of bipropellant rocket using H 2 O 2 for launch stage of ramjet engine was conducted Verification of auto-ignition and stable combustion of H 2 O 2 decomposed jet and Kerosene - Pressure increase about 2 times and maintains stability - Temperature increase over 1000°C - Combustion flame

69. 69/68 Rocket Lab KAIST Conclusion Investigation of auto-ignition and combustion characteristics W/ 5mm diameter nozzle (3.2 bar) - 95% H 2 O 2 : F/O ≤ 0.6, failure of auto-ignition - 90% H 2 O 2 : 0.6 < F/O < 1.00 auto-ignition, combustion detected W/ 4mm diameter nozzle (4.8 bar) - 90% H 2 O 2 : 0.44 ≤ F/O < 1.00 auto-ignition, combustion detected W/ 7mm diameter nozzle (1.6 bar) - Failure of auto-ignition

70. 70/68 Rocket Lab KAIST Conclusion - Auto-ignition occurred over 400°C - At same initial combustor temperature and pressure, F/O is important factor for auto-ignition - Auto-ignition F/O decreases with increase in initial combustor pressure - Auto-ignition occurred under combustor choking condition Possibility of novel concept using H 2 O 2 –Kerosene rocket for launch stage of ramjet propulsion system is ascertained