Casey Allen

Energetic-Nanoparticle-Enhanced Combustion of Liquid Fuels in a Rapid Compression Machine

An aerosol rapid compression machine is developed to investigate energetic-nanoparticleenhanced combustion of liquid fuels using ethanol and aluminum nanoparticles as a model system. An ultrasonic nozzle is used to nebulize neat ethanol and mixtures containing nanoparticles for ignition delay tests in the rapid compression machine. It is determined that 2%-weight nano-aluminum can lead to a dramatic reduction in the ignition delay (90%). The aerosol is introduced to the rapid compression machine through a poppet valve that is optimized by CFD simulations to maximize turbulent mixing and improve charge homogeneity.

Autoignition Behavior of Petroleum-Based and Hydroprocessed Renewable Jet Fuel Blends in a Rapid Compression Machine

A rapid compression machine (RCM) is used to study the autoignition characteristics of JP-8 and JP-5 blended in 50-50 mixtures by volume with their respective camelina-derived hydroprocessed renewable jet (HRJ) fuel at low temperature conditions. The tests employ the direct test chamber (DTC) charge preparation method which allows for high reproducibility of measurements. Ignition delay measurements are compared between the conventional military jet fuels, HRJ fuels, and the 50-50 blends. Measurements are made at compressed pressures of 5, 10, and 20 bar at an equivalence ratio of 1.0 and compressed temperatures between 625 K and 710 K. Additional ignition delay measurements are reported at reduced equivalence ratios of 0.5 and 0.25 at a compressed pressure of 20 bar and temperatures between 635 K and 720 K.

An Experimental Investigation of the Autoignition Characteristics of Camelina-Based Hydroprocessed Renewable Jet Fuel

A rapid compression machine (RCM) is used to study the autoignition characteristics of camelina-based hydroprocessed renewable jet (HRJ) fuel and JP-8 jet fuel at low temperature and low pressure conditions. The tests employ a new approach for creating the fuel/oxidizer gas mixture whereby liquid fuel is injected directly into the combustion chamber and vaporized before the test commences. Reproducibility measurements confirm the validity of this approach for high-fidelity gas-phase kinetic measurements. Ignition delay measurements are compared between camelina HRJ and JP-8 at a compressed pressure of 7 bar, an oxidizer-to-fuel mass ratio of 14.4 and compressed temperatures between 650 K and 800 K. Additional ignition delay measurements for camelina HRJ are reported over the same temperature range with a compressed pressure of 7 bar and an oxidizer-to-fuel mass ratio of 19.