OPTIMISATION OF THE FORMULATION OF A DOUBLE – BASED SOLID PROPELLANT

The study investigated the optimization of the formulation of a double – based solid propellant using Sorbitol as fuel and Potassium nitrate as oxidizer. This research provides an insight into a way of preventing the negative effect of poor propellant formulation on the predetermined rocket mission. The design is based on the fact that specific impulse, temperature, density and thrust of the product are functionally related to specific propellant formulation and these are fitted to multiple regression equations describing responses to optimal formulation using response surface methodology (RSM). From the model equations developed, the potassium nitrate ratio had a positive linear and negative quadratic effect on specific impulse and density and a strong positive linear and strong negative quadratic effect on temperature and thrust. The model fitness value (F- value) of 972.07, 29072.37, 32434.66 and 969.43 implies that the model is significant since there is only a 0.01% chance that an F- value that is large could occur due to noise. The coefficients of determination (R2 ) values gotten are 0.9999, 0.9974, 0.9999 and 0.9974 and the adjusted coefficients of determination (adjusted R2 ) values are 0.9964, 0.9999, 0.9999 and 0.9964 which further validates the model. The optimum performance values obtained are 90.2119 s, 1643.84 K, 1843.02 Kg/m3 and 950.854 N for specific impulse, temperature, density and thrust respectively. These values were in good agreement with the experimental results. An optimum double base propellant formulation of 34.18% sorbitol and 65.82% potassium nitrate can be used in launching rockets and missile systems because of its high specific impulse and thrust.