China's Space Program News Thread


taxiya

Brigadier
Registered Member
Copy paste from 9ifly regarding solid rocket booster development:

《固体火箭发动机技术发展和面临的关键技术问题》:田维平,王立武,王 伟( 中国航天科技集团有限公司第四研究院,西安)
对于航天运载与助推领域,大型化是固体火箭发动机的发展目标。一方面,发展先进整体式大型固体火箭发动机,突破纤维壳体、大型柔性喷管等技术,实现发动机直径 3.5 m、推力 500 t、工作时间 120 s、质量比≥0.93,为全固体运载火箭提供高性能基础级动力;另一方面,发展大型金属壳体分段式固体火箭发动机,突破分段燃烧室对接、大流量高可靠矢量喷管等技术,实现发动机直径 3.5 m、5 段式、推力 1500 t、工作时间120 s、质量比 0.86,为重型运载火箭提供高可靠助推动力

CASC 4th academy's two parallel developments of Solid Rocket Booster:
  1. 500t monolithic SRB as the 1st stage of full solid launch vehicle.
  2. Metal casing segmented SRB, 3.5m diameter, 5 segments, 1500t thrust, burn time 120s, for heavy lift launch vehicle.
It seems that, regardless the final choice of CZ-9, CASC is determined and financed to acquire the capability of building a SLS/Ares type of heavy lift. This also means that YF-90 will complete its development even regardless what CZ-9 uses for its 2nd stage (120t or YF-90).

The 5 segment SRB is equal in thrust to the proposed SLS' 5 segment SRB, but the burn time is half. Meaning the way CASC uses SRB in its envisioned SLS equivalent is very different.
 
Last edited:

OppositeDay

Junior Member
Registered Member
Copy paste from 9ifly regarding solid rocket booster development:

《固体火箭发动机技术发展和面临的关键技术问题》:田维平,王立武,王 伟( 中国航天科技集团有限公司第四研究院,西安)
对于航天运载与助推领域,大型化是固体火箭发动机的发展目标。一方面,发展先进整体式大型固体火箭发动机,突破纤维壳体、大型柔性喷管等技术,实现发动机直径 3.5 m、推力 500 t、工作时间 120 s、质量比≥0.93,为全固体运载火箭提供高性能基础级动力;另一方面,发展大型金属壳体分段式固体火箭发动机,突破分段燃烧室对接、大流量高可靠矢量喷管等技术,实现发动机直径 3.5 m、5 段式、推力 1500 t、工作时间120 s、质量比 0.86,为重型运载火箭提供高可靠助推动力

CASC 4th academy's two parallel developments of Solid Rocket Booster:
  1. 500t monolithic SRB as the 1st stage of full solid launch vehicle.
  2. Metal casing segmented SRB, 3.5m diameter, 5 segments, 1500t thrust, burn time 120s, for heavy lift launch vehicle.
It seems that, regardless the final choice of CZ-9, CASC is determined and financed to acquire the capability of building a SLS/Ares type of heavy lift. This also means that YF-90 will complete its development even regardless what CZ-9 uses for its 2nd stage (120t or YF-90).

The 5 segment SRB is equal in thrust to the proposed SLS' 5 segment SRB, but the burn time is half. Meaning the way CASC uses SRB in its envisioned SLS equivalent is very different.

Also confirms the less than 7% dry mass ratio @Temstar calculated earlier in the thread.

The dry mass ratio for the planned metal cased SRB is 14%.

Assuming China is massively expanding its ICBM arsenal, can a solid fuel core stage shared between the ICBM programme and civilian rockets be more economical than a reusable liquid fuel core stage in virtue of the economy of scale?
 

taxiya

Brigadier
Registered Member
Assuming China is massively expanding its ICBM arsenal, can a solid fuel core stage shared between the ICBM programme and civilian rockets be more economical than a reusable liquid fuel core stage in virtue of the economy of scale?
Your assumption is to use the number in ICBM to lower the unit cost of the booster, so the civilian solid launcher can enjoy a competitive price with reusable liquid rocket.

I would think it is the opposite. That China want to use the number of civilian launches to lower the cost for ICBMs. The Chinese thinking is that military application is pure cost, if not used any weapon is a "waste". To minimize that necessary "waste" is to find usage in profitable civilian application.

This can be seen in that China is the only country that is actively developing solid launching vehicles comparable to liquid launchers, such as CZ-11, and Quizhou series. How large that "scale" is enough to compete with reusable liquid rocket, and whether that is the primary goal are different questions. IMO, I don't think that is the purpose, but a by-product it become competitive. The primary goal is quick launch capability of large payload to SSO and LEO, a scenario where cost is not a question, such as time of war.
 

FairAndUnbiased

Captain
Registered Member
Also confirms the less than 7% dry mass ratio @Temstar calculated earlier in the thread.

The dry mass ratio for the planned metal cased SRB is 14%.

Assuming China is massively expanding its ICBM arsenal, can a solid fuel core stage shared be economical than a reusable liquid fuel core stage in virtue of the economy of scale?
Liquid fuel generally has better specific impulse and better energy density, so is more economical. However a mixed solid - liquid rocket with solid first stage and liquid upper stage is possible.
 

taxiya

Brigadier
Registered Member
The 5 segment SRB is equal in thrust to the proposed SLS' 5 segment SRB, but the burn time is half. Meaning the way CASC uses SRB in its envisioned SLS equivalent is very different.
Correct myself, shuttle, SLS and Ares V's SRB burn time are 120s same as CASC's 5 segment SRB. I must have read wiki page of shuttle wrongly (242 s being impulse rather then 127s burn time). Even that 127s could be kind of wrong or misleading because various source saying that the SRBs are separated at about 120s.

Please, Log in or Register to view URLs content!

Approximately a minute later (two minutes into the
Please, Log in or Register to view URLs content!
phase
), the two
Please, Log in or Register to view URLs content!
have consumed their
Please, Log in or Register to view URLs content!
and are jettisoned from the
Please, Log in or Register to view URLs content!
.
 

Top