Global fuel consumption by commercial airlines has increased each year since 2009 and is predicted to reach an all-time high of 97 billion gallons in 2019.  There is an environmental impact from this: CO~2~ emissions from commercial passenger and freight operations totaled 918 Mt in 2018, or around 2.5% of global energy-related CO~2~ emissions. Emissions from aviation have grown 32% over the past five years.  Coupled with this is a continuous and growing need to satisfy ever-growing electrical power needs on commercial and military aircraft.  The armed services (Army, Navy, Air Force) are continuously trying to enhance UAV (unmanned aerial vehicles) endurance and range across a broad fleet of different aircraft. The commercial Boeing 787 requires about 1.2MWe and is expected to grow. Current technologies used to supply increased on-board power are generally: 1) “burn more fuel and convert through on-board generators” and 2) use additional weight-inefficient and sometimes unsafe battery systems on-board the aircraft.  The aircraft industry is seeking new, innovative ways to satisfy this increasing power demand.  One as-yet-untapped power source is the enormous amount of “waste” thermal energy flowing out jet engine exhaust; some estimates in smaller “by-pass” flow jet engines is several hundreds of kilowatts (e.g., Pratt & Whitney Canada PW545B turbofan).  This quantity is much higher in large jet engines associated with commercial aircraft.  This large waste thermal energy manifests itself in large temperature differences within the by-pass-flow engine exhaust system relative to outside ambient conditions, because of actual by-pass engine design configurations. In small jet engines discussed above core flow temperatures are around 640°C, while by-pass flow temperatures tied to outside ambient conditions at altitude can be -44°C.  There are even larger temperature differentials available in other parts to the engine. This provides a large opportunity to recover some of this thermal energy using various energy conversion technologies. There is a complementary strong desire within the aircraft and engine manufacturing community to reduce the “carbon footprint” of the industry though reduced fuel usage worldwide.  This presentation will discuss the strong need to develop high-performance heat transfer technologies that could harness and convert at least a portion of this thermal energy into useful electrical energy to satisfy growing on-board aircraft electrical needs and enable a corresponding carbon footprint reduction.  In particular, this presentation will demonstrate the latest high-performance, light-weight microchannel heat exchanger designs, and device testing that provides a pathway to recovering and converting aircraft engine waste energy.  It will present and discuss the progress and challenges of integrating the high-performance, light-weight microchannel designs into innovative thermoacoustic power generation (TAPG) systems to deliver power and transfer thermal energy between various aircraft systems and components.  This work will present the challenging TAPG requirements and how they impact the high-performance, light-weight microchannel designs.


Microchannel Heat Transfer Innovations for Energy Conversion Systems in Aircraft Energy Recovery

Division / Sponsors: 
Heat Transfer Division (HTD), Fluids Engineering Division (FED)

Heat Transfer Summer Conference
Paper Proceedings: https://asmedigitalcollection.asme.org/HT/HT2020/volume/83709

18th International Conference on Nanochannels, Microchannels, and Minichannels
Paper Proceedings: https://asmedigitalcollection.asme.org/ICNMM/ICNMM2020/volume/83693

Fluids Engineering Division Summer Meeting
Paper Proceedings: https://asmedigitalcollection.asme.org/FEDSM/FEDSM2020/volume/83716

HT-ICNMM2020 - Virtual Conference, SHTC - Virtual Conference, FEDSM2020 - Virtual Conference

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