SOURCE: AFI
The Aeronautical Development Agency (ADA) is taking a deep dive into innovative cooling solutions for the AMCA (Advanced Medium Combat Aircraft) program. Their focus: active cooling of the engine bay and nozzle, crucial for maintaining stealth capabilities. Fifth-generation stealth aircraft require a delicate balance. Traditional engine bay ventilation systems often rely on inlet scoops to draw in cooling air. However, these scoops can create unwanted radar signatures, hindering the aircraft’s stealth properties.
ADA is exploring the feasibility of an alternative approach – engine bay ventilation using an ejector nozzle. This design eliminates the need for inlet scoops.
The concept involves an ejector nozzle that utilizes the high-velocity exhaust from the engine itself. This exhaust flow creates a low-pressure region, drawing in secondary air from within the engine bay. This secondary airflow helps cool the engine bay and the nozzle, maintaining optimal operating temperatures.
ADA is conducting feasibility studies using Computational Fluid Dynamics (CFD) simulations. These simulations analyze the performance of the engine bay ventilation system under various flight conditions. Parameters like secondary airflow rate, air intake pressure recovery, and pressure distortion are being evaluated to assess the effectiveness and impact of the ejector nozzle system on engine bay cooling and air intake performance.
The initial findings suggest that the ejector nozzle approach holds promise for achieving engine bay ventilation at supersonic speeds (Mach number greater than 0.2). Further research and development are needed to refine the design and ensure its effectiveness across the entire flight envelope of the AMCA.
A successful engine bay ventilation system using an ejector nozzle would be a significant breakthrough for the AMCA program. It would allow the AMCA to maintain optimal engine temperatures while preserving its stealth characteristics, making it a truly formidable next-generation combat aircraft.
Benefits of the Ejector Nozzle Approach
Reduced Radar Signature: By eliminating inlet scoops, the ejector nozzle design offers a potentially stealthier solution.
Improved Aerodynamics: The ejector nozzle may also influence the overall airflow around the aircraft, potentially leading to aerodynamic benefits.