Transient vertical mixing by natural convection in a wide layer (Q1973074)

The paper presents theoretical and experimental study of mixing length for mixing layers which are at least as broad as they are tall. This has been achieved by assuming a priori that the mixing length is linearly proportional to the instantaneous thickness of the mixing layer. The diffusion equation has been solved when the mixing length and thickness of mixing layers are of the same order. The solution has been compared with quantitative measurements of the mixing zero thickness-time history. This is obtained by injecting pure water into the bottom of a wide tank of brine. The authors give an estimate of overall experimental uncertainity. The theory presented in the paper may be readily converted to predict the light release fuel-gas concentration profile during a gas release event.