Laminar plane fountains impinging on a ceiling with an opposing heat flux

The behaviour of unsteady planar strong fountains, impinging on a ceiling with an opposing heat flux on the ceiling, is investigated numerically for image at image and image. The height of the ceiling is varied in image, where image is the half-width of the fountain source, and the non-dimensional gradient of the temperature difference between the fountain source and the ceiling is varied for image. It is found that the fountain does not hit the ceiling, but instead stagnates and spreads at some distance from the ceiling due to the stratification of the fluids in the immediate vicinity of the ceiling. The scaling and direct numerical simulation results show that the augmented spreading distance image has the scaling of image in the range studied, where image is the maximum fountain height, image is the spreading distance measured at image, respectively.