Introduction of a Supercritical Kerosene Test Bench Based on One-Stage Electric Heater with Large Current
A kind of supercritical kerosene heat transfer test bench was introduced in this article. It uses large current to heat the stainless steel tube directly and then the kerosene flowing inside the tube can be heated. A kind of needle valve is used to adjust the kerosene mass flow rate and a kind of backpressure valve is used to adjust the pressure inside the test tube. Insulating materials are laid at the two sides of the tube to prevent electrical leakage. Heat flux is calculated by measurements of the voltage and current. Kerosene is rapidly heated to high temperatures while the wall temperature is below the safety limit by increasing the tube length and thickness. The electric heater could effectively simulate the heat flux of a scramjet engine chamber with a maximum power of about 28KW. Kerosene within 15g/s could be quickly heated to 1000K with this system.
Fuel-Cooled Thermal Management for Advanced Aeroengines
Fuel-cooled thermal management, including endothermic cracking and reforming of hydrocarbon fuels, is an enabling technology for advanced aero engines and offers potential for cycle improvements and pollutant emissions control in gas turbine engine applications. The successful implementation of this technology is, however, predicated on the use of conventional multicomponent hydrocarbon fuels and an understanding of the combustion characteristics of the reformed fuel mixture. The objective of this research is to develop and demonstrate the technologies necessary for utilizing conventional multicomponent hydrocarbon fuels for fuel-cooled thermal management, including the development of the endothermic potential of JP-7 and JP-8 +100, a demonstration of the combustion of supercritical/endothermic fuel mixtures, and conceptual design of a fuel-air heat exchanger. The ability to achieve high heat sinks with existing jet fuels (e.g., JP-7 and JP-8 +100) was demonstrated with a bench-scale test rig operating under flow conditions and passage geometries simulative of practical heat exchangers for aircraft and missile applications. Key measurements included fuel heat sink, reaction products, and extent of conversion: Full-scale sector rig tests were conducted to characterize the combustion and emissions of supercritical jet fuel, and demonstrate the safety and operability of the fuel system, including a fuel-air heat exchanger.
Applications of Endothermic Reaction Technology to the High Speed Civil Transport
The success of strategies for controlling emissions and enhancing performance in High Speed Research applications may be increased by more effective utilization of the heat sink afforded by the fuel in the vehicle thermal management system. This study quantifies the potential benefits associated with the use of supercritical preheating and endothermic cracking of jet fuel prior to combustion to enhance the thermal management capabilities of the propulsion systems in the High Speed Civil Transport (HSCT). A fuel-cooled thermal management system, consisting of plate-fin heat exchangers and a small auxiliary compressor, is defined for the HSCT, integrated with the engine, and an assessment of the effect on engine performance, weight, and operating cost is performed. The analysis indicates significant savings due a projected improvement in fuel economy, and the potential for additional benefit if the cycle is modified to take full advantage of all the heat sink available in the fuel.