armadilloaerospace.com/n.x/Armadillo/Home/News?news_id=164
"We then loaded two liters of peroxide for a long run, which also went flawlessly for 30 seconds. We measured our kerosene flow on this run, and found out just how rich we were actually running – we burned 1.7 liters of kerosene with the 2.0 liters of peroxide, for an O:F of 2.2:1, about three times as rich as optimal. Our true Isp was also quite low, only 151 s. Going to a leaner jet would get us another 10% or so, but we still need to improve our injector to get the rest of the performance we want. We will be happy when we have a measured 200 Isp..."
"All things considered, we are quite happy with the results today. We will continue testing the regen chamber with better injectors, leaner mixtures, and possibly higher pressures, hoping to push the Isp up to 200 or so, and we are laying out what we need to build a regen chamber for the six inch cat packs, which should be good for up to 1000 lbf, which is a valid engine for a single-man space shot vehicle in a differentially throttled cluster of four..."
О дешевизне регенеративно охлаждаемых алюминиевых (!) двигателей...
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"Our oxidizer-only Isp was 246, up from a previous best of 192! We shrank the fuel jet a good chunk, and the oxidizer-Isp increased a bit more. We shrank it some more, and it finally nosed over a bit, which would still be at increasing "true Isp".
We will have to get our sight glass hooked back up so we can measure the kerosene flow, but this was with an 0.040" kerosene jet, while a 0.060" jet resulted in a measured O:F of 2.2:1 on Saturday, so that would put us around 5:1 O:F, which would be a true Isp of 208!"