A Spatial Perspective on the Metallized Combustion Aspect of Rockets

The budding impulse to unravel the mysteries of the universe has driven humankind towards devising space propulsion systems that can lift heavy masses. A solid propellant rocket is a type of space launch vehicle, which usually consists of a main engine surrounded by an array of boosters to provide additional thrust during the initial stages of flight. The boosters help to achieve higher speeds in comparatively smaller durations. The overall efficiency of a rocket is a function of the thermal and the propulsive efficiencies. Improving the overall efficiency by focussing on either one of the two has been successful so far. However, it is impossible to increase both values simultaneously, as they follow an inverse relationship. In this research venture, optimization of the rocket design has been explored for enhancing the concerned efficiency values. In a small-scale replication of the combustion process, the working of a solid rocket is emulated using sparklers and energized candles, with a centrally placed energized candle acting as the main engine, surrounded by sparklers, substituting for boosters. The need to understand the physical and thermal mechanisms involved in actual rocket propulsion and to better comprehend the inter energy conversions that occur between the booster and the main engine, has been the major objective behind this investigation. The primary parameter monitored in this work is the regression rate of the energized candle, values of which have been obtained by exploring various experimental parameters such as interspace distance, number of sources, orientation and configuration of sources (both linear & non-linear). The conventional rocket designs that use linear configurations of boosters were validated through the results obtained and the advantages of non-linear configurations were obtained. To better understand the complexities involved in the heat transfer characteristics of these phenomenon, a new non-dimensional number has been introduced.