dfly9891
Mechanical
- Dec 22, 2009
- 29
I'm designing a rig to test a circulation fan. The system is closed loop with Helium as the working fluid at temp 50K and pressure 100 psi.
I need to measure flow, temp and pressure near and upstream of the fan and measure pressure near and downstream of the fan. Consideration needs to be given to the pipe OD, thickness and material (i.e. weld-on fittings to attach pressure and temp sensors).
The inlet and outlet of the circulating fan's collector (304 stainless) is a female recepticle for 5/8" od piping.
Downstream from the fan outlet (after the temp and pressure instruments) I'm probably going to step down to 3/8" od copper refrigeration piping and run about 50' of it though a LN2 bath to cool the helium. Then I’ll step it back up before the temp, pressure and flow instruments heading toward the fan inlet.
Inlet Pressure 7 [bar]absolute
Pressure Ratio 1.034
Inlet Temperature 50 K (or as close I can get)
Mass Flow Rate about 8 [g/s] , 11 [g/s] corrected
Fan Electrical: 110 VAC 100W, .5 amp (small unit, impeller od is about 1 inch. overall length is about 12 in)
Questions: What material, od and wall thickness would you use for the instrument rail and why? What might be the best way to transition from that od to 3/8” copper refrigeration piping? How would you set up a helium tight flow meter?
I need to measure flow, temp and pressure near and upstream of the fan and measure pressure near and downstream of the fan. Consideration needs to be given to the pipe OD, thickness and material (i.e. weld-on fittings to attach pressure and temp sensors).
The inlet and outlet of the circulating fan's collector (304 stainless) is a female recepticle for 5/8" od piping.
Downstream from the fan outlet (after the temp and pressure instruments) I'm probably going to step down to 3/8" od copper refrigeration piping and run about 50' of it though a LN2 bath to cool the helium. Then I’ll step it back up before the temp, pressure and flow instruments heading toward the fan inlet.
Inlet Pressure 7 [bar]absolute
Pressure Ratio 1.034
Inlet Temperature 50 K (or as close I can get)
Mass Flow Rate about 8 [g/s] , 11 [g/s] corrected
Fan Electrical: 110 VAC 100W, .5 amp (small unit, impeller od is about 1 inch. overall length is about 12 in)
Questions: What material, od and wall thickness would you use for the instrument rail and why? What might be the best way to transition from that od to 3/8” copper refrigeration piping? How would you set up a helium tight flow meter?