Quote from: russianhalo117 on 09/30/2018 08:00 pmQuote from: HMXHMX on 09/29/2018 06:38 pmQuote from: envy887 on 09/29/2018 04:14 amMy first take at labeling the components.I haven't been following this as closely I perhaps should, but that engine looks to me like an expander cycle, not a pre-burner or GG cycle. A fair amount of similarity to the Blue BE-3U upper stage version...Quote from: envy887 on 09/30/2018 05:46 pmThe turbines exhaust into the injector, so it is closed cycle. If it is a closed cycle expander it is unique since it had a short chamber and is some 5 times larger by thrust than any other closed cycle expander.The article explicitly says there are preburners on board and the the PGA engine (Family) is an FRSC engine.I know, and the renders agree with that - except for the plurality of preburners. There is only one duct which splits to feed both of the turbines, so there is only one preburner. Unless they are using serial preburners, which I have never heard of anyone doing and can't think of any reason to do so.
Quote from: HMXHMX on 09/29/2018 06:38 pmQuote from: envy887 on 09/29/2018 04:14 amMy first take at labeling the components.I haven't been following this as closely I perhaps should, but that engine looks to me like an expander cycle, not a pre-burner or GG cycle. A fair amount of similarity to the Blue BE-3U upper stage version...Quote from: envy887 on 09/30/2018 05:46 pmThe turbines exhaust into the injector, so it is closed cycle. If it is a closed cycle expander it is unique since it had a short chamber and is some 5 times larger by thrust than any other closed cycle expander.The article explicitly says there are preburners on board and the the PGA engine (Family) is an FRSC engine.
Quote from: envy887 on 09/29/2018 04:14 amMy first take at labeling the components.I haven't been following this as closely I perhaps should, but that engine looks to me like an expander cycle, not a pre-burner or GG cycle. A fair amount of similarity to the Blue BE-3U upper stage version...
My first take at labeling the components.
The turbines exhaust into the injector, so it is closed cycle. If it is a closed cycle expander it is unique since it had a short chamber and is some 5 times larger by thrust than any other closed cycle expander.
Vulcan, in its statement about Allen’s death, said that plans had been developed for continuing his various ventures after his passing, but did not disclose details.“Paul thoughtfully addressed how the many institutions he founded and supported would continue after he was no longer able to lead them. This isn’t the time to deal in those specifics as we focus on Paul’s family,” said Bill Hilf, chief executive of Vulcan, in the statement.
Stratolaunch Completes First, Full-Scale Preburner Test on PGA EngineNovember 6, 2018Stratolaunch is proud to announce the successful initiation of full-scale development testing of the PGA Engine preburner, marked by the completion of the first hot-fire test of the preburner on November 2.Fully designed and developed by Stratolaunch, the PGA Engine is a high-performing, liquid rocket engine that, once completed, will produce 200,000 lbf of thrust. The hydrogen-oxygen engine will have the highest specific impulse of any rocket engine propellant and will release only water as a byproduct.Designed, fabricated, assembled and tested in less than one year, the full-scale hydrogen preburner will be one of the fastest engine development programs to-date. The team has successfully completed propellant cold flows, igniter activation, and hot-fire sequence development, all culminating to the hot-fire tests.“I am excited to share that Stratolaunch has completed our first successful hot-fire test of the PGA Engine fuel preburner,” said Jeff Thornburg, vice president of propulsion at Stratolaunch. “This is the first step in proving the performance and highly-efficient design of the PGA engine. The hot-fire test is an incredible milestone for both the propulsion team and Stratolaunch.”Not only is the PGA Engine the first U.S. hydrogen-staged combustion engine since the Space Shuttle Main Engine, the Stratolaunch propulsion team has also prioritized the use of additive manufacturing for the development of the engine, enabling rapid prototyping on a much faster scale than traditional methods. This process has resulted in 100 percent additive manufacturing of the preburner. Once completed, the PGA Engine will support multiple configurations of Stratolaunch’s in-house launch vehicles enabling convenient, reliable, and routine access to space.Preburner testing will continue over the coming months, with increases in both the duration and power-levels of the hot-tests. For the latest news and updates, please check out @Stratolaunch and www.stratolaunch.com/news.
Good article. This bit was impressive.The full-scale preburner was designed, fabricated, assembled, and tested in less than one year. Stratolaunch called the campaign “one of the fastest engine development programs to date.”
