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Typical coefficient of discharge for an airlift pump

Typical coefficient of discharge for an airlift pump

Typical coefficient of discharge for an airlift pump

(OP)
Does anyone know where i can obtain a typical Cd for an airlift pump ? needs to be reference-able (if that is a word!)

I understand that there any many empirical formulas in circulation that use two phase flow etc however i need to find the head and flow rate (theoretical and actual) of an airlift when all i have is the actual flow rate, air pressure, outlet area and submergence (oh and assume water = 1000 kgm^-3). All of the formulas out there require inlet velocities etc which i do not possess.

I understand i would only get a rough figure however its better than nothing !

Thank you very much i appreciate it

RE: Typical coefficient of discharge for an airlift pump

Have you looked / searched in this site for "air lift pumps" ?
I found one from 2003 which had some good reference material.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

RE: Typical coefficient of discharge for an airlift pump

Assume a reasonable inlet velocity, 1 m/s for example.

Independent events are seldomly independent.

RE: Typical coefficient of discharge for an airlift pump

Cd is not a parameter directly used with air lift pumps; instead in formulae given in Kent ME"Power" and Perry ChE handbooks, values C's are dependent on the total head of the pump. The velocity of the air bubbles will also be dependent on bubble size if we have air liquid only and that will vary from .53 ft/sec to .83 ft/sec with bubble dia ranging .05in to .38in; with increase bubble size velocity will drop due to surface tension and bubble flattening. With water, it will take about 5.5 cuft of air per cuft of water; with oil wells, that vary from 150 to 50 cuft of air per cuft of oil.
With mixture of solid(S),gas(G) and liquid(L) I've used an article by G.F. Hewitt on Void Fraction, however, I do not have his book anymore for reference, so you'll have to research it in the library. This is the article you want if the mixture fractions are either S,G,L or G,L

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