Design and Performance of a Compact Air-Breathing Jet Hybrid-Electric Engine Coupled With Solid Oxide Fuel Cells

Abstract

A compact air-breathing jet hybrid-electric engine coupled with solid oxide fuel cells (SOFC) is proposed to develop the propulsion system with high power-weight ratios and specific thrust. The heat exchanger for preheating air is integrated with nozzles. Therefore, the exhaust in the nozzle expands during the heat exchange with compressed air. The nozzle inlet temperature is obviously improved. SOFCs can directly utilize the fuel of liquid natural gas after being heated. The performance parameters of the engine are acquired according to the built thermodynamic and mass models. The main conclusions are as follows. 1) The specific thrust of the engine is improved by 20.25% compared with that of the traditional jet engine. As pressure ratios rise, the specific thrust increases up to 1.7 kN/(kg·s−1). Meanwhile, the nozzle inlet temperature decreases. However, the temperature increases for the traditional combustion engine. 2) The power-weight ratio of the engine is superior to that of internal combustion engines and inferior to that of turbine engines when the power density of SOFC would be assumed to be that predicted for 2030. 3) The total pressure recovery coefficients of SOFCs, combustors, and preheaters have an obvious influence on the specific thrust of the engine, and the power-weight ratio of the engine is strongly affected by the power density of SOFCs.

Experimental Activities on a Hydrogen-Powered Solid Oxide Fuel Cell System and Guidelines for Its Implementation in Aviation and Maritime Sectors

“…This aimed to enhance vehicle performance and fuel efficiency, while also exploring the possibility of assuming a central role in propulsion systems [9]. Contextually, researchers began directing their attention toward Unmanned Aerial Vehicles (UAVs), where SOFCs could be employed as propulsion systems, particularly in hybrid configurations [10][11][12][13]. The interest in hydrogen-powered rail vehicles has been steadily growing, with a particular focus on their potential applications in heavy rail transportation.…”

Large-Eddy Simulation of the Boundary Layer Development in a Low-Pressure Turbine Cascade With Passive Flow Control

“…Modern aircraft are designed to have a higher cruising altitude and better engine performance with a larger thrust-to-weight ratio to have a better stealth performance and reduce energy consumption. However, these would lead to the low Reynolds number operation conditions and higher loading of the blade in a low-pressure turbine (LPT), respectively (Houtermans et al, 2004;Praisner et al, 2008;Ji et al, 2021). These characteristics of the LPT stage make the boundary layer on the aft portion of the blade suction side remain laminar and suffer greater pressure gradients.…”

Performance and size optimization of the turbine-less engine integrated solid oxide fuel cells on unmanned aerial vehicles with long endurance

“…However, the fuel cell propulsion systems aforementioned can not be operated at high velocity because the thrust is produced by propellers. Therefore, a turbine-less SOFC jet hybrid engine (hybrid engine) for long endurance and high-velocity missions was first proposed in our previous paper [15][16][17]. The engine combines the merits of the fuel cell engines with high efficiency and combustion engines with high specific power.…”