4 replies to this topic

[Santosh Devde]

How to do relief valve area calculation for highly viscous fluid. When the viscosity is too high (in the range of 50000-100000 Cp)?
is this possible if yes, how or if not, why?

[fallah]

Santosh,

 

In general, using viscosity correction factor, relief area calculation is possible but for such very high viscous fluid considering available viscosity correction charts it might not be possible. Please specify specific gravity of the fluid, then it may be easier to submit a better answer to your query...

[Santosh Devde]

Hi Naser,

 

Thanks for your reply,

 

I tried using viscosity correction factor  from API 520 RP part 1 figure 36, and with some iterations but its coming very high,

I wanted to know can we size PSV for such high viscosity fluids.

 

Density of fluid is 1200 kg/m3 and viscosity is 50000 centipoise.

 

Regards,

Santosh

[fallah]

Santosh,

 

You are right, the viscosity correction factor curve in API 520 Part I is limited to the fluids with viscosities leading to Reynolds Numbers higher than around 35 and isn't applicable for fluids with higher viscosities leading to Reynolds Numbers lower than 35. I think your case falls within the range of Reynolds Numbers lower than 35 and as far as I know there in no specified literature and standard for such range.

Appears the only option for PSV sizing in such high viscous fluid application to be: doing flow tests with the fluid and selection a preliminary size of PSV for the application...

[Santosh Devde]

Thanks Naser,

 

Correct Reynolds number is very less than 35, 

 

Could you please throw some light on "doing flow tests with the fluid and selection a preliminary size of PSV for the application".

or any literature for this topic. It will help me to give some information for this kind of special case.

 

Regards.

Santosh