# Category - Key equations for Process Engineers

## Sample Problem – Vertical Knock Out Drum Sizing Calculations

Sample Problem Statement
Design a vertical gas-liquid separator or a Knock Out Drum for separation of liquid droplets entrained in fuel gas flow. The liquid in...

## Air Compressibility Factor Calculation – Sample Problem

Problem Statement
Calculate the compressibility factor (Z factor) for air at the following temperature and pressure condition -
P = 15 barg
T =...

## Heat Transfer – Conduction of Heat

Conduction of heat in a solid wall is expressed using Fourier's equation for heat conduction,

T : Temperature at a point in wall
θ : Time
k : Thermal...

## Dynamic or Absolute viscosity and Kinematic viscosity

Fluid viscosity is an important fluid property in fluid dynamics. Fluid viscosity represents the frictional resistance within the fluid to shearing force...

## Flow Coefficient

Flow coefficient of a device represents the ease for a fluid flow to pass through the device. High flow coefficient of a device such as restriction orifice or...

## Bernoulli’s Equation

Incompressible Flow
For incompressible fluids, Bernoulli's equations simply states that the combined kinetic energy, gravitational static energy and pressure...

## Net Positive Suction Head definition – NPSH for pumps

Net Positive Suction Head or NPSH for pumps can be defined as the difference between liquid pressure at pump suction and liquid vapor pressure, expressed in...

## Compressibility factor

Compressibility factor of gases is a thermodynamic property which is used to modify the ideal gas equation for real gases.
For Ideal gases, Ideal gas equation...

## Work done in thermodynamic processes

A system can reach from state A to state B following different paths. These paths followed by a system while undergoing a change of state, are termed as...

## Universal Gas Constant

The behaviour of an Ideal gas is described by the following equation,
PV = nRT
where,
P = Pressure (bar, atmosphere, Pa)
V = Gaseous volume (m3, cm3)
n =...

## Specific heat ratio / Adiabatic index

Heat capacity of a system can be defined as the quantum of heat required to increase the temperature of the system by unity.

Specific heat is a property of...

## Line Pressure drop

For any flow through a pipe line, the frictional pressure drop per unitlength of the line depends on the type and phase of thefluid flowing throughthe line...