Process Variables

What are the Process Variables?

Answer: The process variables are

• Flow.
• Pressure.
• Temperature.
• Level.
• Quality i.e. % O2, CO2, pH etc.

Define all the process Variable and state their unit of measurement. ?

Answer: 

Flow

Any fluids or liquids flowing from one place to another place is called flow and it is defined as volume per unit of time at specified temperature and pressure .Conditions, is generally measured by positive-displacement or rate meters.

Units:- kg / hr, litter / min, gallon / min, m3 / hr, Nm3 / hr. (Gases)

Pressure

It is defined as Force per unit Area. P = F/A

Units:- bar, Pascal, kg / cm2, lb / in2.

Level

The height of the water column, liquid and powder etc., at the desired measurement of height between minimum level points to maximum level point is called level. The measurement principle is, head pressure method.

Units:- Meters, mm, cm, percentage.

Temperature

It is the degree of hotness or coldness of a body is called temperature.

Units:- Degree Centigrade, Degree Fahrenheit, Degree Kelvin, Degree Rankin.

Quality

It deals with analysis.( pH, % CO2, % 02, Conductivity, Viscosity )