Heat transfer of premixed butane/air impinging circular flame jet with induced swirl

In addition to the main axial flow of butane/air mixture, two tangential air flows had been used to produce a premixed gasfired impinging circular flame jet with induced swirl. The flame jet system under investigation was small-scale and operated essentially at the low-pressure and laminar flow conditions. The swirl number was estimated, with the aid of the Continuity Equation, to be 0.78. The whole investigation was conducted at Re = 1000 and Φ = 1. The non-dimensional nozzle-to-plate distance (H/d) was varied from 1.0 to 3.0. The radial heat flux distributions on the horizontally placed impingement plate had been measured under various experimental conditions, which were compared with those obtained from a previous study [1] with similar impinging flame jet system without induced swirl. The total heat fluxes obtained on the impingement plate at different H/d ratio had also been measured to identify its effect on the thermal performance of the system. It was shown from the present study that the introduction of swirl to the small-scale, low-pressure and low Reynolds number premixed gas-fired impinging flame jet was feasible. Certainly, more investigations would be required to fully understand its heat transfer characteristics.