Two-Dimensional Dual Jets—A Comprehensive Review of Experimental and Numerical Analyses

A dual jet system, comprising a wall jet flowing tangential to a solid wall and a parallel offset jet, possesses a unique flow field that has proven advantageous in many industrial applications. Despite this, investigations of dual jets are severely underrepresented in the published literature, meaning their flow and heat transfer characteristics are yet to be fully understood. Many published studies dedicated to the characterization of dual jet flows are entirely numerical in nature, and significant discrepancies exist among the reported findings. This can be attributed to the distinct lack of experimental data related to dual jet flows, which has to date prohibited the full validation of any existing dual jet numerical model. The purpose of this report is to perform a comprehensive review of the available dual-jet literature to ascertain the present understanding of dual jet flow behavior and related heat transfer characteristics. An in-depth overview of dual jet flow theory is provided, and the reported effects of varying the major dual jets’ parameters are discussed, e.g., jet Reynolds number, jet offset ratio, and jet velocity ratio. In doing so, the major discrepancies among the relevant dual-jet studies are highlighted and a clear gap in the literature is identified. Recommendations for future studies on dual jets are provided.