The Influence of Source Froude Number and Turbulent Fluctuations on the Development of Turbulent Fountains in Stratified Ambient

Turbulent fountains are widespread natural phenomena with numerous industrial applications. Extensive research has focused on the temporal evolution and maximum height of these fountains, as well as their dependence on Reynolds and Froude numbers. However, the lower boundary of the spreading flow attained by the mixture of the ejected fluid and the surrounding ambient fluid has received little attention. Here, we focus on the dependence of the lower boundary height on the characteristics of the fountain and demonstrate how to control it. Large Eddy simulations were carried out based on a Navier–Stokes solver which implements fully implicit 3D incompressible finite volume method with second-order accuracy in space and time using curvilinear coordinates, and validated with laboratory experiments. Our results present important implications for technological applications of turbulent fountains, particularly in protecting crops from frost. We discuss the potential of our results to improve the efficiency of such applications.