Differential Pressure Across Chiller Barrels
Differential Pressure Across Chiller Barrels
(OP)
Hi Team,
Under near-laboratory conditions and with very accurate instruments, I'm measuring flow through both chilled and condenser water barrels of a chiller. Instead of the expected flow-squared correlation to pressure drop, I'm getting flow to the 1.7 or 1.8 power.
Anyone here ever run into this? I would think that a chilled water tube bundle would behave like a long straight run of pipe and give me flow-squared correlating to pressure drop.
Am I missing something here?
Thanks much!
Under near-laboratory conditions and with very accurate instruments, I'm measuring flow through both chilled and condenser water barrels of a chiller. Instead of the expected flow-squared correlation to pressure drop, I'm getting flow to the 1.7 or 1.8 power.
Anyone here ever run into this? I would think that a chilled water tube bundle would behave like a long straight run of pipe and give me flow-squared correlating to pressure drop.
Am I missing something here?
Thanks much!
Best to you,
Goober Dave
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RE: Differential Pressure Across Chiller Barrels
In Darcy which is considered the more accurate of the two, friction is related to the square of the velocity which we would expect... I wonder if it is the actual friction coefficient of the 'pipe' which changes w/Reynolds number??? I think it can change significantly depending on flow regime you are in... laminar transitional and turbulent which obviously impacts your loss/flow relationship...
I know in the simpler hazen willians they use a somewhat fixed friction value (I think based on pipe type) rather than the calculated f value that Darcy uses. In the Hazen formula, friction loss varies with 1.85 power of the flow/velocity...
Hope this helps.
RE: Differential Pressure Across Chiller Barrels
Dave
Best to you,
Goober Dave
Haven't see the forum policies? Do so now: Forum Policies
RE: Differential Pressure Across Chiller Barrels
Best to you,
Goober Dave
Haven't see the forum policies? Do so now: Forum Policies