Simulation of gas-substrate heat exchange during cold-gas dynamic spraying

• Published in: International journal of thermal sciences Vol. 56; pp. 12 - 18
• Main Authors: Ryabinin, A.N., Irissou, E., McDonald, A., Legoux, J.-G.
• Format: Journal Article
• Language: English
• Published: Elsevier Masson SAS 01-06-2012
• Subjects: Biot number; Cold spraying; Computational fluid dynamics; Dynamics; Fluid flow; Jet impingement; Mathematical analysis; Nusselt number; Spraying; Temperature distribution; Three dimensional; Temperature distribution; Cold spraying; Nusselt number; Jet impingement; Biot number
• ISSN: 1290-0729; 1778-4166
• DOI: 10.1016/j.ijthermalsci.2012.01.007

In this study, the Nusselt numbers of impinging compressible fluid jets originating from a cold-gas dynamic spraying nozzle were determined. A low-pressure cold-gas dynamic spraying unit was used to generate a jet of hot compressed nitrogen that impinged upon flat substrates. Computer codes based on a finite differences method were used to solve the governing 3-D temperature distribution equation for the substrate to produce a non-dimensional relationship between the Nusselt number and the radius of the impinging fluid jet. It was found that the Nusselt number decreased as the non-dimensional radius of the jet from the stagnation point increased. It was found further that for small values of the Biot number, a simplified 2-D approximation of the substrate temperature distribution produced substrate surface temperature profiles that were in close agreement with that determined from the more complex 3-D temperature distribution model.
► The substrate surface temperature under gas jets in the cold spraying process. ► The variation of the Nusselt number with the radius of the spreading jet. ► The agreement between the 2-D and 3-D models of temperature distribution.