<< It's got a full tank of nitrogen and/or peroxide between it and the engine; hard to see how valve chatter pressure waves would survive undamped through all that gas/liquid. Also wouldn't the chatter be above several Hz? >>
To damp, something has to absorb energy. If there's nothing in the system that can respond to a given wavelength, the frequency is transmitted. Some combinations of tanks, structure, and propellant load can actually "ring" at just the wrong frequency, exaggerating rather than damping, certain vibrations. Tight structures tend to ring at higher frequencies. Rubber washers compress and rarefact nicely at the frequencies of interest (generally low sonic to infrasonic). Chatter at high frequencies might also be a lifetime issue because of fretting corrosion. Apologies for dipping in and out of the flow of this--life has gotten busy. I'll miss the meeting tonight--going to Oregon this evening. I've emailed the Ames/Moffett people, no response yet. Will try again. --Best, Gerald _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
