void fraction

Void fraction refers to the proportion of a volume that is occupied by a gas or vapor within a mixture, such as a liquid-gas system. It represents how much of the space is "empty" or filled with gas rather than liquid. For example, if a pipe contains a mixture of liquid and gas, and half of the space is gas, the void fraction is 50%. This concept is important in engineering and fluid dynamics because it influences flow behavior, heat transfer, and system design. Essentially, void fraction quantifies the distribution of gas within a liquid, helping us understand and predict how the mixture will behave.