Compute the pressure due to a volume of gas.

Contents

Interface Function Documentation Page Comments

Interface

#include <codecogs/engineering/thermodynamics/pressure.h>

	double	pressure (double p1, double v1, double v2, double gamma=1.4) Compute the pressure due to a volume of gas.
	Real	cc_thermodynamicsPressure (Real p1, Real v1, Real v2, Real gamma) This function is available as a Microsoft Excel add-in.

Function Documentation

Compute the pressure due to a change in volume of gas, based on the adiabatic expansion

Therefore

where γ is the gas constant, equal to 1.4 for air.

Example 1:

The follow graph show the change pressure when an initial 2m^3 air is expanded or contracted:

Note:

The units for pressure and volume can be interchanged with SI or Imperial systems, so long as the units used for p1 are the same as those in p2; and equally the units of v1 = v2. i.e. You are consistent.

Parameters:

p1	The initial pressure [psi]
v1	The initial volume [ft^3]
v2	The new volume [ft^3]
gamma	The gas constant. Default value = 1.4 (for air)

Returns:

The new pressure at volume v2. [psi]

Authors:

James Bateman (March 2008)