Sunday, October 3, 2010

Introduction to pressure measurement

It is time to know about pressure measurement..

    In general, pressure is represented as force per unit area. The measurement of pressure is one of the most important measurements, as it is used in almost all industries. Some important appilications of pressure measurement is listed.



1. The pressure of steam in a bolier is measured for ensuring safe operating condition of the boiler.
2. Pressure measurement is done in continous processing industries such as manufacturing and chemical industries.
3. Pressure measurement helps in determining the liquid level in tanks and containers.
4. Pressure measurement helps in determining the density of liquids.
5. In many flow meter (such as venturimeter, orifice meter, flow nozzle, etc.,) pressure measurement serves as an indication of flow rate.
6. Measurement of pressure change becomes an indication of temperature (as used in pressure thermometers-fluid expansion type).
7. Apart from this, pressure measurement is also required in day-to-day situations such as maintaining optimal pressure in tubes of vehicle tyres.

Definition of pressure:

            Pressure is the force exerted by a medium (fliud) on a unit area due to the interaction of fluid particles amongst themselves.

The following are the terms related to pressure namely:
1. atomspheric pressure.
2. Absolute pressure.
3. Gauge pressure.
4. Vacuum pressure (Rare fraction or negative pressure).
5. Static pressure.
6. Total or stagnation pressure.
7. Dynamic or impact or velocity pressure.

The next post will describe in detail about the above terms.