An example PV diagram (1912), the area of the enclosed region under the curve representative of PV work, the area of which shown being calculated according to the strip method, or summation of the the areas of the vertical strips. [1]
In thermodynamics, PV diagram, short for pressure volume diagram, indicator diagram, or indicator card, is a plot of the pressure of a given body or system, on the ordinate (vertical axis), against volume on the abscissa (horizontal axis); the body typically existing in the gas state, although this is not always true, which undergoing a transformation or change of state; typically expansion or contraction.
