Pressure Loss

Pressure loss, abbreviated as \(\Delta P\), also called pressure drop, is the difference in pressure between two points, usually caused by friction resistance in the pipe, but moisture can also affect it.  It is a common phenomenon in fluid flow systems and can have various causes and implications.  Pressure loss typically occurs due to these main factors, frictional loss and localized loss.

Pressure loss is an important consideration in the design, analysis, and operation of fluid flow systems.  It affects factors such as flow rate, system efficiency, pump or compressor requirements, and the selection of appropriate pipe sizes and components.  Minimizing pressure loss is often desirable to optimize system performance, reduce energy consumption, and ensure adequate pressure levels at critical points in the system. This can be achieved through careful system design, selection of appropriate materials, optimizing flow velocities, and minimizing flow disturbances.

 

Pressure Loss formula
\(\large{ P_l =  \mu  \; \left( \frac{ l  }{ d_h } \right) \; \left( \rho\;\frac{ v^2 }{ 2 } \right) }\)
Symbol	English	Metric
\(\large{  P_l }\) = pressure loss	\(\large{\frac{lbf}{in^2}}\)	\(\large{Pa}\)
\(\large{ \mu }\)  (Greek symbol mu) = friction coefficient	\(\large{ dimensionless }\)
\(\large{ l }\) = lenght of pipe	\(\large{ ft }\)	\(\large{ m }\)
\(\large{ d_h }\) = hydraulic diameter	\(\large{ ft }\)	\(\large{ m }\)
\(\large{ \rho }\)   (Greek symbol rho) = density	\(\large{\frac{lbm}{ft^3}}\)	\(\large{\frac{kg}{m^3}}\)
\(\large{ v }\) = velocity of fluid	\(\large{\frac{ft}{sec}}\)	\(\large{\frac{m}{s}}\)