Learning Forum

[soudarshinivalve]

Am using ansys aim for finding FLOW COEFFICIENT. so i want to convert pressure unit from pa to psi , and mass flow rate kg/s to us gallon per min. How can i convert those units in ansys aim.

[Naresh Patre]

Hello V Sridharan

If you set the units system as U.S. Customary or U.S. Engineering, the result units of pressure will appear as psi.

 

There doesn't seem any option to get the flow rate result unit as gallon per min.

[soudarshinivalve]

HiNaresh Patre 

thanks for your replay. can i use expressions or calculated value for unit conversion

[soudarshinivalve]

 hiNaresh Patre  i want to use this formula in calculated expressions. if i use this formula for cv value did not have any units. but in ansys aim have units. how can i apply this formula.

thanks

[Naresh Patre]

V Sridharan I will check it and let you know.

[Naresh Patre]

Hello V Sridharan

The flow coefficient is GPM (US gallons per minute) that a valve will pass for a pressure drop of 1 lb/in2 (psi).

 

Using the above formula, the expression in AIM can be written as follows:

 

The units obtained from this calculation are correct as per the definition of flow coefficient.

[soudarshinivalve]

hello Naresh Patre 

my mass flow rate=53.688kg/s=850.95 us gallon per min(kg/s and bar is my ansys aim result)

pressure drop=1bar=14.5038 psi

CV=Q*sqrt(1/dp)=223.44   (it is hand calculation)

i need this value or more or less equal to this value 

[Naresh Patre]

Hello V Sridharan

You will have to use expressions like the one mentioned below:

First, calculate volumetric flow rate as follows:

Volumetric flow rate = mass flow rate (kg/s)/density (kg/m3)*conversion factor

where conversion factor = 15850.323 (1 cubic meter/second = 15850.323 141 gallon/minute [US])

This will give the value of volumetric flow rate i.e. Q in us gallon per min, although the actual units returned by AIM will be different and should be ignored in this case

Now, Cv = Volumetric flow rate*sqrt(1/dp(psi))

Again, you will have to ignore the units that you get in the above expressions.

[soudarshinivalve]

hi Naresh Patre 

thanks for your replay. it will be use full.