Reducing the Specific Fuel Consumption of a Micro-Turbojet Engine by Converting it into a Micro-Turbofan Engine

Despite the wide use of micro-turbine engines in various aerospace fields, these engines consume a relatively high amount of fuel to provide desired thrust. The fuel consumption is a key parameter in the efficiency, endurance and range of an unmanned air vehicle. An effective approach to reduce the fuel consumption of these engines while maintaining the thrust value is to convert them into micro-turbofan engines. In this research, a mixed flow micro-turbofan engine structure derived from a micro-turbojet engine is employed. In order to analyze the performance of this structure, a thermodynamic modeling using matrix iteration method and Newton-Raphson solver is performed for a micro-turbofan engine. The findings of engine modeling are validated against a gas turbine performance simulation software. Afterwards, the required fan module is designed for the converted engine. The operation of the micro-turbofan engine in the steady-state and transient regime is investigated. Comparing the performance of the new engine with the experimental data of baseline engine indicates that despite no change in thrust value, the specific fuel consumption is reduced by 20%.