# how to reduce pressure drop in a 5/16 ss tube

I have a fluid line which passes high density fluid at $60 \text{psi}$. At the end there is a valve. I have a $30 \text{psi}$ dynamic pressure drop in the line valve itself creates a back pressure of $10 \text{psi}$. How do I reduce my pressure drop without changing tube parameters?

-

## 1 Answer

I couldn’t get any answer for this question and so ended up in performing experiments in the lab to find answer by myself. To reduce my dynamic pressure drops in the SS tube.

The factors externally (Without changing tube parameters) which I can vary to reduce dynamic pressure drop in the line is maintaining temperature of the liquid. We know that viscosity reduces by increasing the temperature. I increased the temperature of the liquid in which the liquid starts to flow easier (Reducing Shear stress). The pressure drop is mainly created by major and minor losses and major is ofcourse friction loss.

Increase temperature of the liquid flowing. Creating a back pressure in the system. We can add back pressure by adding a valve (which we can control the flow rate by reducing orifice diameter) Using a booster within the line to generate pressure. Reducing the flow velocity of the liquid as equation rightly says-ΔP=fD x L/D x ρV²/2.

If we can change the parameters of SS tubes, then we can Increase the diameter of the tube (helps reduce flow velocity inside the line) Reduce length of the tube-Less friction losses.

The application of this was to design a heat exchanger. Thought to share these leanings with all of you. i have lot of laboratory tested data regarding effect of temperature Vs viscosity, shear stress, kinematic viscosity, and many more

-