boost pump size for a positive displacement pump

[pauldavid]

1- positive displacement triplex pump
2- suction requirement 60 psi npsh
3- positive displacement triplex pump flow 65 gpm
4- fluid LH2

 

[sshep]

It wasn't clear if there is a question here.
For a PD pump the options to increase flow rate are longer stroke, or higher speed.

 

[TD2K]

Select a booster pump that puts out 65 gpm at 65 psi minimum pressure.

Add a suitable margin in line with the PD's pumps manufacturer. Since any pressure developed by the booster pump doesn't have to be added by the PD, the cost of more head by the booster is just due to the difference in efficiencies. I'd likely be looking at something like 90 psi NPIP (net positive inlet pressure, the equivalent of NPSHA) depending on the discharge pressure from the PD pump.

Be sure to take acceleration head into account, it's a lot more significant for PD style pumps though it can be reduced with suction pulsation dampers.

LH2 liquid hydrogen?

 

[EmmanuelTop]

Liquid Hydrogen is very specific service. I'd suggest you get in contact with specialized manufacturers.

http://www.barber-nichols.com/products/pumps/cryogenic-pumps/liquid-hydrogen-pumps

http://www.airproducts.com/microsit...rt/33969_cryogenic_hydrogen_compressor_ds.pdf

http://www.lindeus.com/en/innovations/hydrogen_energy/fuelling_technologies/cryo_pump.html

Dejan IVANOVIC
Process Engineer, MSChE