Effect of thrust on supersonic gas jet penetration in gas–solid fluidized beds

Most of the jet penetration studies in gas–solid fluidized beds are for subsonic gas jets, for which many correlations can be found in the literature. In this work, horizontal supersonic gas jets, produced by convergent–divergent nozzles, have been studied, and the intent was to investigate the relationship between the thrust produced by supersonic nozzles and the jet penetration. Different nozzle geometries were used, with three gases having different characteristics (air, helium and carbon dioxide) and at different pressures. All the experimental runs were performed with silica sand particles with the same particle size distribution, and the fluidization velocity was set at a constant value of 0.09 m/s.Jet penetration was measured with a set of triboelectric probes, and it was found that the correlation proposed by Merry, although originally developed for subsonic gas jets, fits really well the experimental results. It was also confirmed that jet penetration displays a strong correlation with the thrust produced by the convergent–divergent nozzles.A correlation originally proposed by Benjelloun's has been modified and the corrected correlation gives the best predictions for gas jet penetration

► The penetration of jets issuing from supersonic nozzles in fluidized beds depends on their initial thrust. ► Merry's correlation for the penetration of subsonic jets works well with supersonic jets. ► A modified version of Benjelloun's correlation gives the best predictions for the penetration of supersonic jets.Graphical abstractThe penetration of sonic and supersonic gas jets in fluidized beds was measured with a set of triboelectric probes. Jet penetration displays a strong correlation with the thrust produced by the convergent–divergent nozzles. A correlation originally proposed by Benjelloun's has been modified to give the best predictions for gas jet penetration.Figure optionsDownload full-size imageDownload as PowerPoint slide