Session: 03-01 Ammonia as Fuel and Hydrogen Carrier – Combustion, Storage, and Safety

Submission Number: 179301

Experimental Investigation of a High-Pressure Tubular Flow Reactor for Ammonia Cracking 

Existing literature that documents the decomposition of ammonia explores pressures and flow rates much lower than the operating conditions seen in an aircraft engine. In a conceptual carbon-free turbofan engine using ammonia as a hydrogen carrier, ammonia would be cracked and combusted at pressures up to 40 bar during takeoff and 20 bar during cruise conditions. To characterize cracking behavior at these pressures, an experimental setup was designed to sustain a high-pressure cracking reaction through a circular tube with a catalyst coating. Heat transfer characteristics of the cracker are analyzed for Reynolds numbers of 500-2000; the resulting flow rates are between 1000-4800 SCCM, much higher than those seen in literature. Cracker temperatures and pressures are varied from 400-500 °C and 5-20 bar, respectively, to reflect the operating conditions of an aircraft engine. Residence time is varied independently of the other experimental variables by changing the reactor length. The sensitivity of the overall ammonia conversion with each variable is analyzed. A single-rate kinetic model describing the chemistry in the catalyst layer is developed through computational fluid dynamics (CFD) simulations and is validated using the gathered experimental data. The results of this study enable future analysis of high-pressure, high-flow rate ammonia reactors in aviation.

Presenting Author: Benjamin Turner University of Central Florida

Presenting Author Biography: Benjamin Turner is a graduate research assistant at the University of Central Florida involved in research contributing to sustainable aviation.

Authors:

Benjamin Turner University of Central Florida
Andrew Menendez University of Central Florida
Saqib Shahzad University of Central Florida
Mairah Ahmed University of Central Florida
Jesse Chotiner University of Central Florida
Marcel Otto University of Central Florida
Richard Blair University of Central Florida
Jayanta Kapat University of Central Florida