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An investigation was conducted on the performance and emissions characteristics of two Fischer-Tropsch (F-T) synthetic kerosenes, Gas-to-Liquid (GTL) S8 and Coal-to-Liquid (CTL) Iso-Paraffinic Kerosene (IPK), in a high compression ratio research engine with separate combustion chamber and using neat ULSD as a baseline. A 50% and a 70% by mass blend S8 with ULSD and a 50% and a 70% by mass blend of IPK with ULSD were analyzed for performance and emissions at 5, 6, and 7 bar Indicated Mean Effective Pressure (IMEP) and 2400 rpm. Additionally, neat S8, neat IPK, and neat ULSD were investigated in the Constant Volume Combustion Chamber (CVCC) for Ignition Delay (ID), Combustion Delay (CD), and Derived Cetane Number (DCN). S8 was found to have the highest DCN at 62 with very short ID and CD while IPK was found to have the lowest DCN at 26 and with the longest ID and CD. ULSD has a DCN between the two F-T fuels at 48. As a result of its long ID and CD, IPK showed extended regions of Low Temperature Heat Release (LTHR) and Negative Temperature Coefficient Region (NTCR) in the CVCC. It was also found that neat IPK, 50ULSD50IPK, and 30ULSD70IPK exhibit little to no ringing events at peak pressure and after High Temperature Heat Release (HTHR). In the research engine, peak heat release for ULSD, 50ULSD50S8, and 50ULSD50IPK was found to be 24.2 J/CAD, 20.5 J/CAD, and 23.4 J/CAD respectively. Due to the increase of the DCN with the addition of S8 to the blend, the 50ULSD50S8 blend exhibited minimal difference between the pre-chamber and the main chamber as it ignites earlier in the cycle with the flame front traveling quickly to the main chamber. IPK, however, had a short physical ignition delay and a long chemical ignition delay, as indicated by its low DCN, takes longer to ignite and creates a more homogeneous mixture in the highly turbulent pre-chamber. This causes a spike in heat release in the pre-chamber before the flame front propagates to the main chamber. This resulted in 50ULSD50IPK having the highest Peak Pressure Rise Rate (PPRR) and 50ULSD50S8 having the lowest PPRR. While both fuel blends reduced the soot emissions due to their low aromatic content, 50ULSD50IPK showed a 25% reduction in soot when compared to ULSD while 50ULSD50S8 showed only a 6% reduction in soot when compared to neat ULSD. There was a increase in CO emissions with the addition of IPK and a reduction in CO at low load with the addition of S8. With both F-T fuels, CO2 and NOx were found to decrease. 

An investigation into emissions differences and their correlations with differing combustion characteristics between F24 and Jet-A was conducted. Raw emissions data was taken from a single stage jet engine by a FTIR gas analyzer. Measurements of H₂O, CO₂, CO, NOx, and total hydrocarbon emissions (THC) were taken at 60K, 65K, and 70K RPM. At 70K RPM Jet-A and F-24 the emissions were similar at approx.: 4% H₂O, 3% CO₂, 970 PPM CO, 28 PPM NOx. Jet-A THC emissions were approx.: 1200 PPM THC, F24 THC emissions were lower by over 60%. The significantly lower amount of THC emissions for F24 suggests more complete combustion compared to Jet-A. 

The Coal-To-Liquid (CTL) synthetic aviation fuel, Iso-Paraffinic Kerosene (IPK), was studied for ignition delay, combustion delay, pressure trace, pressure rise rate, apparent heat release rate in an experimental single cylinder indirect injection (IDI) compression ignition engine and a constant volume combustion chamber (CVCC). Autoignition characteristics for neat IPK, neat Ultra-Low Sulfur Diesel (ULSD), and a blend of 50%IPK and 50% ULSD were determined in the CVCC and the effects of the autoignition quality of each fuel were determined also in an IDI engine. ULSD was found to have a Derived Cetane Number (DCN) of 47 for the batch used in this experimentation. IPK was found to have a DCN of 25.9 indicating that is has a lower affinity for autoignition, and the blend fell between the two at 37.5. Additionally, it was found that the ignition delay for IPK in the CVCC was 5.3 ms and ULSD was 3.56 ms. This increase in ignition delay allowed the accumulation of fuel in the combustion chamber when running with IPK that resulted in detonation of the premixed air and fuel found to cause high levels of Ringing Intensity (RI) when running neat IPK indicated by the 60% increase in Peak Pressure Rise Rate (PPRR) when compared to ULSD at the same load. An emissions analysis was conducted at 7 bar Indicated Mean Effective Pressure (IMEP) for ULSD and the blend of 50% ULSD and 50% IPK. With the addition of 50% IPK by mass, there was found to be a reduction in the NO_x, CO₂, with a slight increase in the CO in g/kWh. 

The effectiveness of obstacle avoidance response safety systems such as ADAS, has demonstrated the necessity to optimally integrate and enhance these systems in vehicles in the interest of increasing the road safety of vehicle occupants and pedestrians. Vehicle-pedestrian clearance can be achieved with a model safety envelope based on distance sensors designed to keep a threshold between the ego-vehicle and pedestrians or objects in the traffic environment. More accurate, reliable and robust distance measurements are possible by the implementation of multi-sensor fusion. This work presents the structure of a machine learning based sensor fusion algorithm that can accurately detect a vehicle safety envelope with the use of a HC-SR04 ultrasonic sensor, SF11/C microLiDAR sensor, and a 2D RPLiDAR A3M1 sensor. Sensors for the vehicle safety envelope and ADAS were calibrated for optimal performance and integration with versatile vehicle-sensor platforms. Results for this work include a robust distance sensor fusion algorithm that can correctly sense obstacles from 0.05m to 0.5m on average by 94.33% when trained as individual networks per distance. When the algorithm is trained as a common network of all distances, it can correctly sense obstacles at the same distances on average by 96.95%. Results were measured based on the precision and accuracy of the sensors’ outputs by the time of activation of the safety response once a potential collision was detected. From the results of this work the platform has the potential to identify collision scenarios, warning the driver, and taking corrective action based on the coordinate at which the risk has been identified. 

Investigations were conducted using mass blends of Iso-Paraffinic Kerosene (IPK) and Fischer-Tropsch Synthetic Kerosene (S8) to produce a synthetic surrogate for aerospace F-24. Due to the fossil fuel origin of F-24, the introduction of a synthetic surrogate would create a sustainable aviation fuel (SAF) with sources obtained from within the United States. An analysis of ignition delay (ID), combustion delay (CD), derived cetane number (DCN), negative temperature coefficient (NTC) region, Low-Temperature Heat Release region (LTHR) and High-Temperature Heat Release (HTHR) was conducted using a PAC CID 510 Constant Volume Combustion Chamber (CVCC). The fuels examined in this study are neat IPK, neat S8, neat F-24, and by mass percentages, as follows: 75IPK 25S8, 52IPK 48S8, 51IPK 49S8, 50IPK 50S8 and 25IPK 75S8. The DCN values determined for IPK, S8, and F-24 were 26.92, 59.56 and 44.35 respectively. The influence of IPK present in the blends increases CD, thus reducing the DCN significantly. The fuel blend of 50IPK 50S8 was observed to be the closest match to F-24 when comparing DCN, ID and CD. The surrogate blends were determined to have a lower magnitude of peak pressure ringing compared to that of the neat S8 and F-24, this is due to the extended NTC region caused by the IPK present in the blend. During further refinement of the surrogate blend, the Apparent Heat Release Rate (AHRR) curve for the 51IPK 49S8 fuel blend was found to have the closest match to the AHRR of F24. The surrogate blend 50IPK 50S8 was shown to have the smallest percent difference and best match during the LTHR stage, compared to F-24, while 52IPK 48S8 had the smallest percent difference for the energy released during LTHR. The ID and CD of the 25/75% blends were too dissimilar from the F-24 target to be considered as a surrogate. A Noise Vibration Harshness (NVH) analysis was also conducted during the combustion of the three neat fuels in the CVCC. This analysis was conducted to relate the ID, CD, HTHR and ringing to the vibrations that occur during combustion. Neat S8 was observed to have the most vibrations occurring during the combustion process. Additionally, the HTHR was observed to have a distinct pattern for the three neat fuels and the combustion of these fuels was quieter overall. 

Research was conducted to determine combustion characteristics such as: ignition delay (ID), combustion delay (CD), combustion phasing (CA 50), combustion duration, derived cetane number (DCN) and ringing intensity (RI) of F24, for its compatibility in Common Rail Direct Injection (CRDI) compression ignition (CI) engine. The first part of this study is investigating the performance of Jet-A, F24, and ultra-low sulfur diesel #2 (ULSD) using a constant volume combustion chamber (CVCC) followed by experiments in a fired CRDI research engine. Investigations of the spray atomization and droplet size distribution of the neat fuels were conducted with a Malvern Mie scattering He-Ne laser. It was found that the average Sauter Mean Diameter (SMD) for Jet-A and F24 are similar, with both fuels SMD droplet range between 25–29 micrometers. Meanwhile, ULSD was found to have a larger SMD particle size in the range of 34–40 micrometers. It was observed during the study, utilizing the CVCC, that the ID and CD for neat ULSD and Jet-A are nearly identical while the combustion of F24 is delayed. F24 was found to have longer durations of both ID and CD by approx. 0.5 ms. This results in a lower DCN for the fuel of 43.5, whereas ULSD and Jet-A have DCNs of 45 and 47 respectively. The peak AHRR for ULSD and Jet-A are nearly identical, whereas F24 has a peak magnitude of approx. 20% lower than ULSD and Jet-A. It was found that both aviation fuels had significantly fewer ringing events occurring after peak high temperature heat release (HTHR), a trend also observed in the CRDI research engine. Neat F24, Jet-A and ULSD were researched in the experimental engine at the same thermodynamic parameters: 5 bar indicated mean effective pressure (IMEP), 50°C (supercharged and EGR) inlet air temperature, 1500 RPM, start of injection (SOI) 16°BTDC, and 800 bar of fuel rail injection pressure as the baseline parameters in order to observe their ignition behavior, low temperature heat release, combustion phasing, and combustion duration. It was found that the ignition delay of F24 and Jet-A was greater than ULSD, approx. 5% for both aviation fuels. This ignition delay also affected the combustion phasing, or CA 50, of the aviation fuels. The CA 50 of the aviation fuels was delayed by approx. 2% compared to ULSD. Jet-A had a nearly identical combustion duration compared to ULSD, however F24 had an extended combustion duration which was approx. 3% longer than that of ULSD and Jet-A. It was discovered with the accumulations of these delays in ID, CD, CA50, that the RI of the aviation fuels were reduced. F24 was discovered to have more delays, and the RI correlates with these results having a 70% reduction in RI compared to ULSD.