Nuri (KSLV-II)
KSLV-II Nuri launching from the Launch Pad 2 at Naro Space Center, 21 October 2021.
Has useOrbital launch vehicle
Manufacturer
Country of originSouth Korea
Project cost 1.96 trillion; US$1.7 billion (spaceport included) [2]
Size
Height47.2 m (155 ft) [3]
Diameter3.5 m (11 ft)
Mass200,000 kg (440,000 lb)
Stages3
Capacity
Payload to Low Earth orbit (300 km) [4]
Mass2,600 kg (5,700 lb)
Payload to Low Earth orbit (600~800 km)
Mass1,500 kg (3,300 lb)
Launch history
StatusActive
Launch sitesNaro Space Center, LC-2
Total launches1
Success(es)0
Failure(s)1
Notable outcome(s)0
First flight21 October 2021, 08:00 UTC
People or cargo transportedDummy satellite
First stage
Height21.6 m (71 ft)
Diameter3.5 m (11 ft)
Powered by4 KRE-075 SL
Maximum thrust2,942 kN (661,000 lbf) [4]
Specific impulse261.7 seconds (Sea level),
298.6 seconds (Vacuum) [5]
Burn time127 seconds
PropellantJet A / LOX
Second stage
Diameter3.5 m (11 ft)
Powered by1 KRE-075 Vacuum
Maximum thrust788 kN (177,000 lbf) [4]
Specific impulse315.4 seconds (Vacuum) [4]
Burn time148 seconds
PropellantJet A / LOX
Third stage
Height3.5 m (11 ft)
Diameter3.5 m (11 ft)
Powered by1 KRE-007 Vacuum
Maximum thrust68.7 kN (15,400 lbf) [4]
Specific impulse325.1 seconds (Vacuum)
Burn time498 seconds
PropellantLOX / Jet A-1

Nuri (Korean: 누리, meaning "world" ), also known as KSLV-II (Korean Space Launch Vehicle-II),[6] is a three-stage launch vehicle, the second one developed by South Korea and the successor to Naro-1 (KSLV-1).[7] Nuri is developed by Korea Aerospace Research Institute (KARI).[8][9][10][11] All three stages use indigenously developed launch vehicle engines, making Nuri the first indigenously developed Korean orbital launch vehicle (the Naro-1 launch vehicle used Russian-made first stage). The South Korean government has set SpaceX as a "role model", striving to develop relatively cheap and reliable rockets competitive enough for the commercial launch market.

On 21 October 2021, it had its first flight at 08:00 UTC and it launched a 1,500 kg (3,300 lb) dummy satellite payload into what was planned to be a 700 km (430 mi) Sun-synchronous orbit (SSO). However, despite the payload reaching the targeted apogee (700 km), the third stage shut down about 46 seconds earlier than planned and the payload did not achieve orbital speed.[11][12][13]

Specification

Nuri is a three-stage launch vehicle. The first stage booster uses four KRE-075 SL engines generating 266.4 tons of thrust with a specific impulse of 289.1 seconds. The second stage booster uses a single KRE-075 Vacuum engine, which has a wider nozzle for increased efficiency in vacuum with a specific impulse of 315.4 seconds. The third stage booster uses one KRE-007 engine with a specific impulse of 325.1 seconds. Both engine models use Jet A as fuel and liquid oxygen (LOX) as oxidizer.[citation needed]

Future versions

Further improvements will be added after the success of KSLV-II program, mainly increasing the thrust of the KRE-075 from 744 kN (167,000 lbf) to 849 kN (191,000 lbf) and specific impulse from 261.7 seconds to 315.4 seconds. There are also plans on making the engine lighter by methods such as removing the pyrotechnic ignitor or limiting its gimbal range. This will allow the payload capacity of the modified KSLV-II to increase from 1.5 tons to 2.8 tons.[14]

Development

Engines development

KRE-075 sea level engine

An artist's render of Nuri's 75-ton-class engine
An artist's render of Nuri's 75-ton-class engine
KRE-075 engine
KRE-075 engine
Fuel Jet A / LOX
Thrust 66.6 tf (SL), 75.9 tf (Vacuum) [5]
Specific Impulse 298.6 seconds [5]
Height 2.9 m
Diameter 2 m
Cycle Gas generator

The KRE-075 engine was developed after the 30 tf engine development program.[16]

KRE-075 vacuum engine

Fuel Jet A-1/LOX
Thrust 80.3 tf (Vacuum) [5]
Specific Impulse 315.4 seconds [5]
Cycle Gas generator

KRE-007 engine

Fuel Jet A-1/LOX
Thrust 7.0 tf [5]
Specific Impulse 325.1 seconds [5]
Cycle Gas Generator

KSLV-II TLV

The Test Launch Vehicle (TLV) was a single stage launch vehicle (with a planned two stage version), qualifying the performance of the KRE-075 engine which powers the KSLV-II. The TLV was 25.8 m (85 ft) in length, 2.6 m (8 ft 6 in) in diameter, and with a mass of 52.1 tons. The main-stage liquid rocket propellant engine was fully gimballed.[17][18] With the 2nd stage engine installed, the two-stage version of TLV could perform as a small satellite launch vehicle.[19]

2018 flight

Wet Mass 52.1 tons [20]
Dry Mass 38 tons
Height 25.8 m
Diameter 2.6 m
Stages 1
Engine 1 KRE-075
Payload mass simulator

The TLV was launched from the Naro Space Center in Goheung, South Jeolla Province, on 28 November 2018. The main objective of the first suborbital flight was for the single-stage rocket's main engine to burn 140 seconds, reaching a 100 km altitude before splashing down in the sea between Jeju Island and Okinawa Island.[21]

The maiden flight was first delayed from 25 October 2018 for one month, due to abnormal readings detected in the launch vehicle propellant pressurization system.[22] The test flight was then rescheduled for 28 November 2018, at 07:00 UTC (16:00 KST). No payload was to be placed into orbit.[23]

The launch of the TLV while deemed successful with its main engine burning for 151 seconds in a 10-minute flight,[24] was not broadcast live.[25] After reaching a maximum altitude of 209 km (130 mi), the launch vehicle stage splashed down in the Pacific Ocean, 429 km (267 mi) southeast of Jeju Island.[26]

As the TLV was meant to serve as a test craft, and as the flight ended in a success, there was not a second TLV launch.

GEO KSLV

An upgraded variety of KSLV-II for geostationary equatorial orbit is under development. It will cluster four KRE-090 engines in the core stage, with four side boosters equipped with one KRE-090 engine each. The second stage will be powered with a vacuum-optimized variety of the same KRE-090 engine (KRE-090V), and the third stage will implement a newly developed KRE-010V oxidizer-rich staged combustion engine.[27]

Usage

Nuri will be used in launching several Earth observation satellites, such as KOMPSAT, medium-class satellites and LEO reconnaissance satellites. It is planned to support South Korea's Moon exploration mission to send orbiters and landers. Nuri will be South Korea's first launch vehicle to enter the commercial launch service market. The launch cost is estimated to be around US$30 million, which is cheaper than its Asian counterparts. This will allow for South Korea to provide cheap launch services for Southeast Asia countries.

An improved version of Nuri is expected to launch a Korean lunar lander by 2030.

See also

References

  1. ^ "한국 토종 우주발사체 누리호는 300개 기업이 함께 만들고 있다". dongascience.donga.com. 25 February 2021. Retrieved 26 February 2021.
  2. ^ "과학기술정보통신부".
  3. ^ "Korea Space Launch Vehicle KSLV-II". Korea Aerospace Research Institute.
  4. ^ a b c d e "대한민국, 이제는 누구? - 한국형발사체 "누리호"!".
  5. ^ a b c d e f g "7톤/75톤급 엔진의 스펙/성능 + 누리호 발사대 설계".
  6. ^ "South Korea launches first homegrown space rocket Nuri". BBC News. 21 October 2021. Retrieved 22 October 2021.
  7. ^ "[출처: 중앙일보] 설계부터 제작까지 100% 국산 로켓 내달 발사". JoongAng Ilbo. 7 September 2018.
  8. ^ "South Korea delays launch of first homegrown space rocket". Yonhap News Agency. 29 December 2020.
  9. ^ Ko, Jun-tae (7 June 2019). "Space: The final frontier, but not for much longer". Korea JoongAng Daily. Retrieved 2 October 2019.
  10. ^ "Korea Space Launch Vehicle KSLV-II". Korea Aerospace Research Institute. Retrieved 7 December 2016.
  11. ^ a b "South Korea's KSLV-II conducts maiden launch". NASASpaceFlight.com. 21 October 2021. Retrieved 21 October 2021.
  12. ^ "South Korea test launches 1st domestically made space rocket".
  13. ^ 이원주 (21 October 2021). "(3rd LD) South Korea fails to put dummy satellite into orbit". Yonhap News Agency. Retrieved 21 October 2021.
  14. ^ "누리호 75톤급 엔진의 개량, 정지궤도 투입, 페이로드 옵션 그리고 재사용에 대하여".
  15. ^ "Hanwha Techwin to Produce Liquid Rocket Engine for Korea Space Launch Vehicle". 비즈니스코리아 - Business Korea. 26 January 2016. Retrieved 7 February 2019.
  16. ^ 한국항공우주연구원(KARI). "[KARI]연비가 향상된 로켓엔진 연소시험(100초) 공개". Archived from the original on 18 November 2021. Retrieved 7 February 2019 – via YouTube.
  17. ^ 한국항공우주연구원 (10 September 2018). "올 10월로 다가올 #시험발사체 조립 장면 타임랩스 영상으로 만나 보시죠!pic.twitter.com/25hDmf2lAg". twitter.com. Retrieved 7 February 2019.
  18. ^ "사진 > KARI IMAGE". kari.re.kr. Retrieved 7 February 2019.
  19. ^ "누리호 75톤급 엔진 시험발사체를 활용한 "소형발사체" 후속 개발에 대하여 (메탄 엔진을 사용하는 2단) > KARI IMAGE".
  20. ^ https://i.servimg.com/u/f48/19/39/35/83/scree261.jpg
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  22. ^ "S. Korea delays test launch of space rocket engine". Yonhal News Agency. 17 October 2018. Retrieved 7 February 2019.
  23. ^ 한국항공우주연구원 (13 November 2018). "11월 28일, 한국형발사체 '누리호'의 엔진시험을 위한 시험발사체 발사가 추진될 예정입니다.pic.twitter.com/9eOHhufcym". twitter.com. Retrieved 7 February 2019.
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  25. ^ 한국항공우주연구원 (27 November 2018). "#시험발사체 발사 성공! 발사 모습을 영상으로 공개합니다.pic.twitter.com/lTkonvL7ax". twitter.com. Retrieved 7 February 2019.
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