Vacuum pressure and absolute pressure - thermodynamics, Mechanical Engineering

Vacuum (Or Vacuum pressure) (Pvacc):

It is pressure of fluid, which is always less than atmospheric pressure. Pressure in a steam condenser is one such example. It can be measured by a pressure gauge but the gauge reads on negative side of atmospheric pressure on dial. The vacuum signifies difference between absolute pressure and atmospheric pressures.

Absolute Pressure (P abs):

It is pressure of fluid, which is measured with respect to the absolute zero pressure as the reference.

Absolute zero pressure can occur only if molecular momentum is zero, and this condition occurs when there is perfect vacuum. Absolute pressure of fluid can be more or less than atmospheric depending upon, whether gauge pressure is expressed as absolute pressure or vacuum pressure.

Inter relation between various types of pressure representations. It is shown in Figure given, which can be expressed as follows.

pabs = patm  + pgauge

pabs = patm  - pvace

330_Vacuum pressure and absolute pressure.png

Posted Date: 10/15/2012 1:18:55 AM | Location : United States







Related Discussions:- Vacuum pressure and absolute pressure - thermodynamics, Assignment Help, Ask Question on Vacuum pressure and absolute pressure - thermodynamics, Get Answer, Expert's Help, Vacuum pressure and absolute pressure - thermodynamics Discussions

Write discussion on Vacuum pressure and absolute pressure - thermodynamics
Your posts are moderated
Related Questions
Q. Design the Nozzle Connections ? Nozzle design shall be such that if the actual combined thickness of the shell or head and reinforcing pad exceeds 50 mm, either integrally r

Navy divers are called to rescue a group of office workers trapped in a basement under floodwater in Leeds, UK. The only access to the basement is via a 1.5 x 1.5 m horizontal hatc

Kinetics: Define Kinetics. What is plane motion? Sol: Kinetics is that branch of mechanics, which deals with force system that produces acceleration and resulting motio

Derivation of displcement equation of cycloidal motion related to follower

System of force

Cell Control And Modeling   Various numbers of modeling systems and cell control have been developed to date. Researchers have worked many on three broad regions: scheduling;


The space truss is supported by a ball-and-socket joint at D and short links at C and E. Determine the force and stress in each member and state if the members are buckle or

What is the magnitude of frictional force after perfect rolling begins and why? solution) After pure rolling begins,frictional force is 0. This is because the velocity of he c

Question. In the system shown below, the force exerted by the free jet issuing from the sharp-edged circular nozzle and impinging on the small circular plate is just su±cient to k