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Publications (129)
An investigation of the performance and emissions of premixed combustion of a synthetic paraffinic kerosene sustainable aviation fuel (SAF) consisting of hydroprocessed esters and fatty acids (HEFA) was conducted using a CRDI research engine with ultra-low sulfur diesel (ULSD) as a reference. In a constant volume combustion chamber (CVCC), HEFA exh...
In this study, Hydro-processed Esters & Fatty Acids (HEFA), FT synthetic paraffinic kerosene (S8), with F-24, & Jet-A as reference, were analyzed for their performance and fuel characteristics.
The spray characteristics of each fuel were evaluated utilizing a Malvern Spraytec He-Ne Laser. The Sauter Mean Diameter (SMD) was determined to be 14.24 μm...
Development and evaluation of a novel design of mass reduced aircraft wing ribs through topology optimization is reported herein. For comparison, the same examination is performed on ribs with normal internal geometry. The wing rib design is based on the Gulfstream G650 transonic jet. The rib is divided into three segments for analysis based around...
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...
div class="section abstract"> An investigation of the performance and emissions of a Fischer-Tropsch Coal-to-Liquid (CTL) Iso-Paraffinic Kerosene (IPK) was conducted using a CRDI compression ignition research engine with ULSD as a reference. Due to the low Derived Cetane Number (DCN), of IPK, an extended Ignition Delay (ID), and Combustion Delay (C...
div class="section abstract"> 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 H<sub>2</sub>O, CO<sub>2</sub>, CO, NOx, and total hydrocarbon emissions (...
div class="section abstract"> Alternative fuels are sought after because they produce lower emissions and sometimes, they have feedstock and production advantages over fossil fuels, but their wear effects on engine components are largely unknown. In this study, the lubricity properties of a Fischer-Tropsch Gas-to-Liquid alternative fuel (Synthetic...
div>Emissions and effects of climate change have prompted study into fuels that reduce global dependence on traditional fuels. This study seeks to investigate engine performance, thermochemical properties, emissions, and perform NVH analysis of Jet-A and S8 using a single-stage turbojet engine at three engine speeds. Experimental Jet-A results were...
div class="section abstract"> 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 chamb...
div class="section abstract"> 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 e...
In this study, iso-paraffinic kerosene (IPK) was analyzed for ignition delay, combustion delay, pressure trace, pressure rise rate and, apparent heat release rate in an experimental single cylinder indirect injection (IDI) compression ignition engine as well as in a constant volume combustion chamber (CVCC). Neat IPK, neat ULSD, and a by-mass blend...
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...
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 stud...
A study was conducted to determine the characteristics of Low Temperature Heat Release, Derived Cetane Number, and the Vibrations, produced by the combustion of aerospace F24 using Jet-A as a baseline in a Constant Volume Combustion Chamber. The Ignition Delay and Combustion Delay for F-24 were found to be 4.04 ms and 5.71 ms with a DCN resulting a...
The lack of the sulfur beneficial lubricity in ultra-low sulfur diesel (ULSD) may lead to premature wear and failure of diesel-fuel systems. Mixing of small percentages of, for instance, biodiesels and other biofuels is typically used to add lubricity in ULSD. N-butanol has been recently proved to mix in or replace diesel without compromising engin...
Research was conducted to observe the correlation of ignition delay, combustion delay, the negative temperature coefficient region (NTCR), and the low temperature heat release region (LTHR), in a constant volume combustion chamber (CVCC) in relation to blended amounts of iso-paraffinic kerosene (IPK) by mass with Jet-A and their derived cetane numb...
View Video Presentation: https://doi.org/10.2514/6.2021-3488.vid The field of aerospace is one of the largest growing fields of engineering to date and accounts for one of the largest margins of transportation globally. With this in mind the environmental impact of transportation is of upmost concern as aviation fuels can contribute heavily to the...
A detailed comprehensive study of a proposed V-shaped turbine rotor is performed in order to examine its structural and aerodynamic characteristics. The structural analysis section of this work determined the most structurally sound blade geometry from 3 different blade geometries. Using the chosen blade profile, 8 rotor models are developed and ar...
The pollution from aerospace transportation is rapidly becoming the largest source of greenhouse gas (GHG) emissions. The FAA expects aviation emissions to almost triple by 2050, making the aerospace industry responsible for the release of approximately 25% of the global carbon dioxide budget. These aviation emissions, including CO2 and NOx, as wel...
Many nations and organizations are committing to achieving the goal of 'Vision Zero' which aims to bring the number of road deaths close to zero by the year 2050. The core of the strategy is a safe transportation system with optimized vehicles and transportation routes. The industry continues to develop integrated safety systems to make vehicles sa...
A fuel blend consisting of 10% S8 by mass (a Fischer-Tropsch synthetic kerosene), and 90% ULSD (Ultra Low Sulfur Diesel) was investigated for their combustion characteristics and impact on emissions during RCCI (Reactivity Controlled Compression Ignition) combustion in a single cylinder experimental engine utilizing a 65% by mass n-butanol port fue...
The use of biodiesels in internal combustion engines leads to tribology concerns because significant oil dilution occurs when biodiesels leak into the oil pan. Dilution by biodiesels may substantially alter oil lubricity and lead to reduced viscosity, which produce tribological changes on engine materials. It is also possible that such oil-biodiese...
During ordinary internal-combustion engine operation, biodiesels partially mix in the engine-oil, leading to increased surface degradation, as premature wear. Biodiesels are blends of methyl esters as main components, which are dependent on the source feedstock and may lead to different surface effects on engine materials. In this preliminary study...
Combustion, noise and vibrations produced by n-Butanol and Oleic Acid Methyl Ester (MO) in Reactivity Controlled Compression Ignition (RCCI) were investigated. The Cetane Number was determined using a Constant Volume Combustion Chamber (CVCC) for MO100, ULSD, and n-Butanol and found to be 73.8, 47.2, and 16 respectively. In the case of the MO20Bu80...
This paper reports the progress of catalysts for improving the hydrocarbon compounds in bio-oil obtained from catalytic pyrolysis of biomass. In addition, the effects of the other operating conditions, such as temperature, type of biomass, heating rate, vapors residence time, carrier gas, and hydrogen donor on the yield and properties of bio-oil ha...
The purpose of the study was to investigate the correlation between thermal characteristics of neat Iso-Paraffinic Kerosene (IPK) in relation to Low Temperature Heat Release (LTHR), ignition delay, and combustion delay within the Negative Temperature Coefficient region (NTC), utilizing a Box-Behnken design matrix. There were 15 trials of 3 control...
The focus of this study is to reduce harmful NOx and soot emissions of a compression ignition (CI) engine using reactivity-controlled compression ignition (RCCI) with n-Butanol. RCCI was achieved with the port fuel injection (PFI) of a low reactivity fuel, n-butanol, and a direct injection (DI) of the highly reactive fuel ULSD #2 (Ultra Low Sulfur...
High reactivity gas-to-liquid kerosene (GTL) was investigated with port fuel injection (PFI) of low reactivity n-butanol to conduct reactivity controlled compression ignition (RCCI). In the preliminary stage, the GTL was investigated in a constant volume combustion chamber, and the results indicated a narrower negative temperature coefficient (NTC)...
LTC was researched by introducing an 80% mass fraction of n-butanol in reactivity controlled compression ignition (RCCI) mode. A 60% mass fraction of n-butanol was port fuel injected (PFI) and the additional 20% was directly injected through a blend of n-butanol (Bu) with Fischer-Tropsch gas to liquid synthetic paraffinic kerosene (GTL) or ULSD as...
Direct Injection of methyl oleate and PFI of n-butanol were used to conduct Reactivity Controlled Compression Ignition (RCCI) and minimize exhaust emissions in reference to conventional diesel combustion. Methyl oleate was investigated for validation of a single fatty acid methyl ester as a surrogate for biodiesel in engine operation. An experiment...
Nanofluids are suspensions of nanoparticles in ordinary coolants, but their tribological effects on heat-exchanger materials are unknown. Previous research has explored wear from distilled-water-base nanofluids only, while most engine-coolants are alcohol solutions in water. This article presents testing of aluminum and copper by jet impingement of...
Use of biodiesels in internal combustion engines leads to oil dilution because unburned biodiesel reaches the engine oil pan, and its lower volatility and early aging can enhance degradation of oil lubricity. The authors conducted previous research in a pin-on-disk tribometer showing that oil dilution (of SAE 15W40 mineral oil contaminated by known...
Direct injection (DI) of cotton seed biodiesel (CS100) with port fuel injection (PFI) of n-butanol was used for producing Premixed Controlled Compression Ignition (PCCI) to achieve low-temperature combustion (LTC) and obtain lower gaseous emissions in comparison to ULSD#2 (ultra-low sulfur diesel). PFI engine operation was compared to the combustio...
When specific fractal geometries are used in the design of fins or heat sinks, the surface area available for heat transfer can be increased while the system mass can be simultaneously decreased. In order to assess the thermal performance of fractal fins for application in the thermal management of electronic devices, an experimental investigation...
This works experimentally investigates the thermal performance of extended surfaces inspired by the first four fractal iterations of the Sierpinski carpet fractal pattern in a free convection environment. Fractal fins inspired by the Sierpinski carpet fractal pattern can result in an increase in surface area for convective heat transfer coupled wit...
Jet-A was investigated in RCCI (Reactivity Controlled Compression Ignition) given that the fuel is readily available and has a similar cetane number compared to ultra-low sulfur diesel (ULSD#2). To promote emissions’ control, RCCI was conducted with direct injection (DI) of Jet-A and PFI (port fuel injection) of n-butanol. Combustion and emission c...
The combustion in an experimental medium duty direct injected engine was investigated in a dual mode process known as partially premixed compression ignition (PPCI). Both a common rail fuel injection system and port fuel injection (PFI) system have been custom designed and developed for the experimental single cylinder engine in order to research t...
An increased emphasis on renewable energy in recent years stems from diminishing supplies of fossil fuels. Add to that an ever-increasing global demand for energy and the conditions for a sustained push towards alternative, renewable forms of energy are clearly present. Biodiesel can be regarded as one such source of alternate energy. It is a renew...
Active research is being conducted to enable the integration of an alternate energy sources so as to replace petroleum based fuels. However, this research has been confined primarily within the auspices of a research laboratory. Of the various alternate energy source available today, biodiesel constitutes perhaps the most dominant and promising alt...
The growing research interest on nanofluids, the suspensions of nano-size powders in ordinary fluids with enhanced cooling properties, has led the authors to study surface modifications (i.e., possible erosion-corrosion effects) from nanofluid interactions with typical heat-exchanger materials. This article discusses existing instruments and the ra...
In this paper the use of alternative fuels — synthetic kerosene based — were investigated in a small aircraft gas turbine engine to determine their sound and vibrations signature at Georgia Southern University’s Aerospace Engine Laboratory. Three types of fuels were used: a natural gas, a coal derived synthetic kerosene and Jet-A as a reference fue...
Performance of an experimental diesel engine was investigated when fueled with CTL20 (80% ULSD#2 (ultra-low sulfur diesel) blended with 20% Fischer-Tropsch coal-to-liquid (CTL) fuel. CTL fuel was selected given its potential as an alternative fuel that can supplement the ULSD supply. Combustion and emissions were studied in a common rail, superchar...
The need to reduce the sound and vibration characteristics in the aerospace industry is continuously increasing because of the need to meet FAA regulations, to reduce noise pollution, and to improve customer satisfaction. To improve customer satisfaction, aircraft and engine manufacturers must work to control sound and vibration levels so that pass...
Nanofluids, the suspensions of nano-size powders in ordinary fluids, are of technical interest for their enhanced cooling properties, but their possible erosion-corrosion effects on cooling-system materials are mostly unknown. This paper discusses the rationale for designing and developing a new test-rig with flow-through parallel to the tested sur...
Aero gas turbine engines generate high levels of sound across a wide frequency spectrum. The total sound energy produced by the engine is composed of multiple thermodynamic sources, including the air intake, combustion, and exhaust. The focus in this research is the investigation of the combustion noise. The combustion process is complex and depend...
Horizontal axis wind turbines (HAWTs) are the dominating technology in large scale energy production utilizing the wind power. With these structures, HAWTs continually becoming more massive in size to produce the most energy possible, greater stresses are imposed on the blades of these turbines. The purpose of this study was to analyze the stresses...
Autonomous vehicles provide an opportunity to reduce highway congestion and emissions, while increasing highway safety. Intelligently routed vehicles will also be better integrated with existing traffic patterns, minimizing travel times. By reducing the time wasted in traffic; harmful emissions will consummately be reduced. Well-designed autonomous...
The performance of an indirect injection engine fueled with a biodiesel blend was investigated at 2400 rpm and 6 bar IMEP. The single cylinder experimental engine was run using C50 and compared to a ULSD#2 baseline. Brassica carinata oilseed was studied as it can potentially provide improvements for existing fuel infrastructures. Cylinder pressure...
Ground vehicles with autonomous navigation require medium range external sensing for early obstacle detection and terrain mapping. Both are essential for path planning. The conventional method for accomplishing this is achieved by very complex and expensive LiDAR sensors with 32 to 64 individual lasers rotating rapidly and taking readings from the...
The demand for wind energy as a renewable source is rising substantially. A growing interest exists in utilizing potential energy conversion applications in areas with less powerful and less consistent wind conditions. In these areas, vertical-axis wind turbines (VAWTs) possess several advantages over the conventional horizontal-axis type. Savonius...
This study investigated the RCCI (Reactivity Controlled Compression Ignition) of PFI (Port Fuel Injection) of n-butanol with direct injection (DI) of a high linoleic acid content biodiesel, cottonseed (CS100). The experimental omnivorous-fuel engine was operated at 1400 rpm and 6 bar indicated mean effective pressure (IMEP) with 20% cooled EGR. The...
In this study, the combustion and emissions characteristics of a new biodiesel and biodiesel blend in a direct injection (DI), experimental diesel engine and was compared to ultra-low sulfur diesel #2 (ULSD#2) at 1500 rpm and 4 bar indicated mean effective pressure (IMEP). The biodiesel blend, C90+BU10, included 90% brassica carinata (25% erucic ac...
This investigation focused on the combustion and performance of an indirect injection (IDI) diesel engine powered by a non-edible biodiesel blend, Brassica Carinata. This oilseed has become an attractive non-edible feedstock for biodiesel in the United States, given potential agronomical advantages. A small bore, single cylinder IDI engine was run...
This study investigates combustion and emissions of Jet-A in an indirect injection (IDI) compression ignition engine and a direct injection (DI) compression ignition engine at 4.5 bar IMEP and 2000 RPM. The Jet-A was blended with ULSD that resulted in 75%Jet-A and 25% ULSD#2 by mass. Both engines were instrumented with Kistler pressure sensors in t...
In this study, Premixed Charge Compression Ignition (PCCI) was investigated with alternative fuels, S8 and n-butanol. The S8 fuel is a Fischer Tropsch (FT) synthetic paraffinic kerosene (SPK) produced from natural gas. PCCI was achieved with a dual-fuel combustion incorporating 65% (by mass) port fuel injection (PFI) of n-butanol and 35% (by mass)...
Diesel engines provide the necessary power for accomplishing heavy tasks across the industries, but are known to produce high levels of noise. Additionally, each type of fuel possesses unique combustion characteristics that lead to different sound and vibration signatures. Noise is an indication of vibration, and components under excessive vibratio...
This study compares combustion of Jet-A in an indirect injection (IDI) compression ignition engine and a direct injection (DI) compression ignition engine at the same load and speed. The Jet-A was blended (75Jet-A): 75% Jet-A and 25% Ultra Low Sulfur Diesel # 2 (ULSD) by mass. Both engines had a load of 4.5 bars Indicated Mean Effective Pressure (I...
The continuous improvement of this world is based on technological advancement. And the technological advancement is directly related to the utilization of energy. The demand of energy is creeping up every day due to increase of population, industrial and agricultural advancement. But the conventional energy sources are becoming limited which is ul...
In this study, the combustion and emissions characteristics of Reactivity Controlled Compression Ignition (RCCI) obtained by direct injection (DI) of S8 and port fuel injection (PFI) of n-butanol were compared with RCCI of ultra-low sulfur diesel #2 (ULSD#2) and PFI of n-butanol at 6 bar indicated mean effective pressure (IMEP) and 1500 rpm. S8 is...
The noise of diesel engines is dependent upon numerous factors such as: load, speed, fuel injection strategies and fuel type, design of the piston, piston-pin and cylinder and their tolerances, bearings, valves and rocker arm clearances, and designs of the manifolds.
In this study, engine sound and vibrations analysis have been conducted using two...
This study evaluates the performance of an indirect injection (IDI) diesel engine fueled with cotton seed biodiesel while assessing the engine's multi-fuel capability. Millions of tons of cotton seeds are available in the south of the US every year and approximately 10% of oil contained in the seeds can be extracted and transesterified. An investig...
In this study, a Premixed Charge Compression Ignition (PCCI) obtained by sequential dual fueling strategy of n-butanol port fuel injection (PFI) and direct injection of ULSD#2 was investigated against binary mixtures combustion (defined as premixed in the tank) of n-butanol and ultra-low sulfur diesel (ULSD#2) with the same n-butanol to diesel rati...
Nanofluids are nano-size-powder suspensions studied as enhanced alternatives to ordinary cooling fluids. But the wear and erosion effects from their interactions with heat-exchanger materials are largely unknown. The authors' research on evaluation methodologies for such surface-change phenomena includes the development of novel test rigs and asses...
Nanofluids are nanosize-powder suspensions that are of interest for their enhanced thermal transport properties. They are studied as promising alternatives to ordinary cooling fluids, but the tribiological effects of nanofluids on cooling-system materials are largely unknown. The authors have developed methodology that uses jet impingement on typic...
Emissions of Unburned Hydrocarbons (UHC) from diesel engines are a particular concern during the starting process, when after-treatment devices are typically below optimal operating temperatures. Drivability in the subsequent warm-up phase is also impaired by large cyclic fluctuations in mean effective pressure (MEP). This paper discusses in-cylind...
This study investigates the combustion, emissions, and performance of biodiesel produced from poultry fat FAME (fatty acid methyl esters) in an indirect injection (IDI) engine. The poultry fat FAME blends were evaluated against ultra-low sulfur diesel #2 (ULSD#2) at 2600 rpm at 100% engine load. The tested biodiesel blends of poultry fat FAME inclu...
This study presents the combustion and emissions characteristics of Reactivity Controlled Combustion Ignition (RCCI) produced by early port fuel injection (PFI) of low reactivity n-butanol (normal butanol) coupled with in cylinder direct injection (DI) of cottonseed biodiesel in a diesel engine. The combustion and emissions characteristics were inv...
Natural convection heat transfer in rectangular enclosures is important in many real-world engineering applications. Included in these applications are the energy efficient design of buildings, operation and safety of nuclear reactors, solar collector design, passive energy storage, heat transfer across multi-pane windows, thermo-electric refrigera...
Nanofluids are nano-size-powder suspensions in liquids that are of interest for their enhanced thermal transport properties. They are studied as promising alternatives as compared to ordinary cooling fluids, but the effects of nanofluids on wall materials are largely unknown. The authors developed an instrument that uses a low-speed jet on material...
In this study the Reactive Controlled Combustion Ignition (RCCI) obtained by early port fuel injection (