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A Split-Cycle engine fueled with methane has been constructed and operated at the University of Windsor. A split-cycle engine consists of two interconnected cylinders working together to preform the four engine strokes. Cylinder 1 preforms intake and compression strokes while cylinder 2 is where combustion, expansion and exhaust occur. The connecting high pressure crossover passage is where methane is injected, resulting in a well pre-mixed air-fuel mixture. Transfer occurs to the combustion cylinder near TDC, resulting in intense small scale turbulence that leads to short combustion durations under 30° CA. Short durations are achieved despite low engine speeds of 850-1200 rpm, late combustion phasing and part loads. Of note is the lean limit of operation of the engine at the equivalence ratio Φ = 0.85, which is high compared to other natural gas engines which have limits around Φ = 0.6.

This paper describes the application of the Fourier Amplitude Sensitivity Test (FAST) method [1] to investigate the effect of uncertainty in design parameters on the thermal system performance of vehicle underbody components. The results from this study will pinpoint the design parameters which offer the greatest opportunity for improvement of thermal system performance and reliability. In turn, this method can save engineering time and resources. An analytical model was developed for a vehicle underbody system consisting of a muffler, heat shield, and spare tire tub. The output from this model was defined as the temperature of the spare tire tub. The majority of the input parameters in this model deviate from their nominal values due to environmental factors, wear and ageing, and/or variation in the manufacturing process.

The increased availability of natural gas (NG) in the U.S. has renewed interest in the application to heavy-duty (HD) diesel engines in order to realize fuel cost savings and reduce pollutant emissions, while increasing fuel economy. Reactivity controlled compression ignition (RCCI) combustion employs two fuels with a large difference in auto-ignition properties to generate a spatial gradient of fuel-air mixtures and reactivity. Typically, a high octane fuel is premixed by means of port-injection, followed by direct injection of a high cetane fuel late in the compression stroke. Previous work by the authors has shown that NG and diesel RCCI offers improved fuel efficiency and lower oxides of nitrogen (NOx) and soot emissions when compared to conventional diesel diffusion combustion. The work concluded that NG and diesel RCCI engines are load limited by high rates of pressure rise (RoPR) (>15 bar/deg) and high peak cylinder pressure (PCP) (>200 bar).

Reactivity controlled compression ignition (RCCI) combustion employs two fuels with a large difference in auto-ignition properties that are injected at different times to generate a spatial gradient of fuel-air mixtures and reactivity. Researchers have shown that RCCI offers improved fuel efficiency and lower NOx and Soot exhaust emissions when compared to conventional diesel diffusion combustion. The majority of previous research work has been focused on premixed gasoline or ethanol for the low reactivity fuel and diesel for the high reactivity fuel. The increased availability of natural gas (NG) in the U.S. has renewed interest in the application of compressed natural gas (CNG) to heavy-duty (HD) diesel engines in order to realize fuel cost savings and reduce pollutant emissions, while increasing fuel economy. Thus, RCCI using CNG and diesel fuel warrants consideration.

Research regarding higher efficiency engines and renewable energy has lead to HCCI engine technology as a viable option with the ability to utilize a variety of fuels. With a larger focus on environmental effects the ability of HCCI engines to produce low levels of NOx and potentially other combustion products is another attractive feature of the technology. Biomass gas as a renewable primary fuel is becoming more predominant regarding internal combustion engine research. The simulated fuel in this study replicates compositions derived from real-world gasification processes; the focus in this work corresponds to fuel composition variations and their effects regarding combustion phasing and performance. There are three biomass gas fuel compositions investigated in this study. All compositions consisted of combustibles of CH₄, CO, and H₂ accompanied by CO₂ then balanced with N₂. The CH₄ and CO₂ constituents of each fuel mixture are held constant at 2% and 5% respectively.

The detailed flow, combustion process and emissions are studied within a In-Direct Injection (IDI) type diesel engine fueled with isooctane using a three-dimensional CFD code known as integrated CKL (CHEMKIN-KIVA-LES) solver that has been successfully developed by the authors to capture the details of turbulence flow structures and chemical kinetics. This CKL solver features three-dimensional turbulent two-phase flow and combustion with one equation k-Δ Large Eddy Simulation (LES) model for turbulence and CHEMKIN for chemical kinetics. The CKL solver was validated using the experimental data from modified KUBOTA D905 IDI type diesel engine converted to HCCI engine. Then the CKL solver is employed to study the effect of fuel injection strategies on the HCCI engine combustion process.

The HCCI combustion mode features characteristics that uniquely position it to facilitate the convergence of gasoline and diesel engine technologies. The ability of HCCI combustion to accommodate a broad variety of fuels is one such characteristic. In this work the viability of a simulated biomass gas that resembles in its composition so-called producer gas is investigated. The paper reports on a single-cylinder HCCI engine's indicated performance when fuelled with the biomass derived gaseous fuels. There were two biomass gas fuel compositions used in this study. Both compositions contained the same amount of CH₄, CO₂, and N₂, and they differed by the H₂ to CO ratio; for Composition 1 the ratio was 10% to 25%, and for Composition 2 it was 15% to 20%. The indicated performance of the HCCI engine was evaluated based on in-cylinder cycle-resolved pressure measurements.

This paper investigates the expansion of the HCCI operating range and combustion control by use of internal fuel reforming with subsequent reduction of NO emissions through Exhaust Gas Recirculation (EGR). The study is focused on multi-step simulation of the engine cycle, comprised of a fuel reformation cycle and a HCCI combustion cycle, with and without EGR. The study is carried out using a single-zone well-stirred reactor model and established reaction mechanisms. The HCCI engine cycle is fueled with a lean mixture of air and ethanol. This study demonstrates that supplementing EGR with internal reforming reduces the NO emissions level. Furthermore, the study shows that internal fuel reforming extends the operational range of HCCI engines into the partial load region and is effective in the combustion onset control. However, the model requires several enhancements in order to moderate the cycle pressure rise and pressure magnitude, and to lower the cycle temperatures and NO emissions.

This paper presents a fundamental thermodynamic modeling approach to study internal combustion engines. The computations of the thermodynamic functions, especially availability, have been developed to seek better energy utilization, analyze engine performance and optimize design of spark ignition (SI) engines fueled with compressed natural gas (CNG), by using both the first and the second law analyses. A single-zone heat release model with constant thermodynamic properties is built into the air cycle simulation, while a more comprehensive two-zone combustion model with burning rate as a sinusoidal function of crank angle is built into the fuel/air thermodynamic engine cycle simulation. The computations mainly include pressure, unburned and burned zone temperature, indicated work, heat loss, mass blowby, availability destruction due to combustion, fuel chemical availability, availability transfer with heat, availability transfer with work and availability exhaust to the environment.

The paper addresses two important issues in the design and operation of liquid LPG (Liquid Petroleum Gas) port injected engines: unacceptable HC (hydrocarbon) emission during cold starts and long hot start times. The poor cold start performance of these vehicles has been traced to deposits forming within the fuel injectors. The long hot start times have been attributed to vaporization of the fuel within the fuel rail during hot soak. The experimental research into solutions for both of these problems is reported in the paper.

This research involved studying the effects of adding small amounts of hydrogen or hydrogen and oxygen to a gasoline fuelled spark ignition (SI) engine at part load. The hydrogen and oxygen were added in a ratio of 2:1, mimicking the addition of water electrolysis products. It was found that the effects of hydrogen addition (≈ 2.8% of the fuel by mass, ≈ 60% by volume) decreased as the fuel/air equivalence ratio approached ϕ = 1. When operating at ϕ ≤ 0.8, the torque, indicated mean effective pressure (imep) and NO emissions increased and cycle-to-cycle variation decreased with hydrogen addition. The improvements in engine performance and increase in NO emissions were related to a faster burn rate shown by a decrease in burn duration with the addition of hydrogen. Further, the addition of hydrogen only and hydrogen and oxygen in a ratio of 2:1 were compared. The extra oxygen had little effect on engine performance other than an increase in NO exhaust concentration ∼ 500 ppm.

The effects of the addition of small amounts of molecular and atomic hydrogen/oxygen on laminar burning velocity, pollutant concentrations, and adiabatic flame temperatures of premixed, laminar, freely propagating iso-octane flames are investigated using CHEMKIN kinetic simulation package and a chemical kinetic mechanism at different equivalence ratios. It is shown that hydrogen/oxygen additives increase the laminar burning velocities. Increased hydroxyl (OH) concentrations resulted in reduced carbon monoxide (CO) emissions in every stoichiometric ratios investigated. Additives also increased the adiabatic flame temperature of iso-octane/air combustion, thereby causing increased NOx concentrations for all additives at all stoichiometries.

Highly accurate cylinder pressure data can be acquired using a wall-mounted and water-cooled quartz piezoelectric transducer. However, this type of transducer does not satisfy the cost and packaging constraints when used in a production engine application. A potential solution to these issues that has been the interest of many is the much smaller and less expensive optical fiber based pressure transducer. This research compares Kistler piezoelectric transducers to Optrand optical fiber transducers. The influence of the transducer type and mounting arrangement on the quality of cylinder pressure data was examined. The transducers were evaluated on a DaimlerChrysler 4.7L V-8 Compressed Natural Gas fuelled test engine. The analysis method is comprised of examining measured individual cycle and ensemble-averaged cylinder pressure records to assess the quality of the data and its usefulness for engine management.

The fuel called E-85 can be burned effectively in engines similar to the engines currently mass-produced for use with gasoline. Since the ethanol component of this fuel is produced from crops such as corn and sugar cane, the fuel is almost fully renewable. The different physical and chemical properties of E-85, however, do require certain modifications to the common gasoline engine. The Windsor - St. Clair team has focused their attention to modifications that will improve fuel efficiency and reduce tailpipe emissions. Other modifications were also performed to ensure that the vehicle would still operate with the same power and driveability as its gasoline counterpart.