For most positive displacement compressors the torque isn't really higher at low rpm, it's just a problem of getting it to pop over center the first time. The idea offered by others to use an electric clutch such as on automobile air conditioning compressors, along with a flywheel should work for any size compressor power matched to the turbine. Also Ron's idea of a compression release can work just fine. Obviously you can't release refrigerant to the atmosphere, but you can have a sealed diaphragm solenoid valve that dumps from the high pressure outlet to the low pressure inlet. When the compressor is not running both sides are at the same pressure - assuming a fixed orifice expansion valve is used. It may be the initial starting resistance is not due to the outlet pressure, but to the interstage pressure on a dual piston pump. In that case the compression release would be between the interstage point and the inlet. The interstage point may be internally ported, so to put a compression release there may require drilling and tapping into the compressor body. Before going to that extent, I'd try the flywheel/clutch system.
Joe h-hydro.com --- In [email protected], davis ron <[EMAIL PROTECTED]> wrote: > > Dear Adrian, > > I think that it would be worthwhile to investigate > this possibility. > The questions of start up torque for the compressor > and a control system (if any) would have to be > addressed. I had no problem starting a small > compressor with my Watermotor model 90 with 18m meters > of head. The model 150 would have about twice as much > torque with the same head. But how would we be able to > know if it would start a 1.5--2.5 h.p. compressor? > What about a compression release like I had on a big > Stihl chainsaw? Do we have any refrigeration experts > around here? ------------------------ Yahoo! Groups Sponsor --------------------~--> Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/FGYolB/TM --------------------------------------------------------------------~-> Does your company feature in the microhydro business directory at http://microhydropower.net/directory ? If not, please register free of charge and be exposed to the microhydro community world wide! NOTE: The advertisements in this email are added by Yahoogroups who provides us with free email group services. The microhydro-group does not endorse products or support the advertisements in any way. More information on micro hydropower at http://microhydropower.net To unsubscribe: send empty message to [EMAIL PROTECTED] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/microhydro/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
