|
| Abstract No.: |
|
Scheduled at:
|
Tuesday, May 10, 2016, Auditorium 10:50 AM
Cold Gas Spraying I
|
|
| Title: |
Analytical evaluation of temperature distribution within a substrate under an impinging compressed hot air jet
|
|
| Authors: |
Amirhossein Mahdavi* / University of Alberta, Canada
Andre McDonald/ University of Alberta, Canada
|
|
| Abstract: |
The temperature distribution within the substrate under an impinging compressed hot air jet was studied, and this study was motivated by the major impact of the gas-substrate heat exchange on the microstructure and quality of the coating in cold-gas dynamic spraying. In this regard, a mathematical model was developed to solve a 3-D heat conduction equation to determine the temperature distribution within the substrate. A low-pressure cold spray unit was utilized to cause the impingement of a compressible air jet on a flat substrate from a stationary nozzle. Fast-response thermocouples were used to determine the surface temperature of the substrate. Experimental data was used with the analytical solution of temperature distribution in order to estimate the heat transfer coefficient between the hot gas and the substrate. It was found that the heat transfer coefficient was highly dependent on the distance from the stagnation point of the impinging air jet. Furthermore, the results were compared to previous theoretical correlations for heat transfer coefficient for compressible flow. It was concluded that the modified forms of the previous correlations for heat transfer coefficient could be applied to a wide range of conditions in cold spraying to estimate the temperature distribution within the substrate.
|
|