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The rapid increase in the sophistication of vehicle automation demands development of evaluation protocols tuned to understanding driver-automation interaction. Driving simulators provide a safe and cost-efficient tool for studying driver-automation interaction, and this paper outlines general considerations for simulator-based evaluation protocols. Several challenges confront automation evaluation, including the limited utility of standard measures of driver performance (e.g., standard deviation of lane position), and the need to quantify underlying mental processes associated with situation awareness and trust. Implicitly or explicitly vehicle automation encourages drivers to disengage from driving and engage in other activities. Thus secondary tasks play an important role in both creating representative situations for automation use and misuse, as well as providing embedded measures of driver engagement.

A correlation was developed to predict the ignition delay of PRF blends at a wide range of engine-relevant operating conditions. Constant volume simulations were performed using Cantera coupled with a reduced reaction mechanism at a range of initial temperatures from 570-1860K, initial pressures from 10-100atm, oxygen mole percent from 12.6% to 21%, equivalence ratios from 0.30-1.5, and PRF blends from PRF0 to PRF100. In total, 6,480 independent ignition delay simulations were performed. The correlation utilizes the traditional Arrhenius formulation; with equivalence ratio (φ), pressure (p), and oxygen mole percentage (xo2) dependencies. The exponents α, β, and γ were fitted to a third order polynomial with respect to temperature with an exponential roll-off to a constant value at low temperatures to capture the behavior expressed by the reaction mechanism. The location and rate of the roll-off functions were modified by linear functions of PRF.

The University of Wisconsin-Madison Snowmobile Team has designed and constructed a clean, quiet, high performance snowmobile for entry in the 2008 Society of Automotive Engineers' Clean Snowmobile Challenge. Built on a 2003 cross-country touring chassis, this machine features a 750 cc fuel-injected four-stroke engine equipped with a fuel sensor which allows operation ranging from regular gasoline to an 85% blend of ethanol and gasoline (E85). The engine has been customized with a Mototron control system which allows for full engine optimization using a range of fuels from E00 to E85. Utilizing a heated oxygen sensor and a 3-way catalyst customized for this engine by W.C. Heraeus-GmbH, this sled reduces NOx, HC and CO emissions by up to 89% to an average specific mass of 0.484, 0.154, 4.94 g/kW-hr respectively. Finally, the Mototron system also allowed Wisconsin to extract another 4 kW from the Weber 750cc engine; producing 45 kW and 65 Nm of torque.

Cylinder liners exert a major influence on engine performance, reliability, durability and maintenance. Various combinations of nonmetallic reinforcements and coatings have been used to improve the tribological performance of sleeves or surfaces used in compressors and internal combustion engines in four stroke, two stroke and rotary configurations. In this paper we report the use of a hybrid composite containing silicon carbide and graphite in an aluminum alloy matrix to improve the performance of various small engines and compressors. Material properties of the base material, as well as comparative dynamometer testing, are presented.

Cycle-to-cycle variation in combustion phasing and combustion rate cause knock to occur differently in every cycle. This is found to be true even if the end gas thermo-chemical time history is the same. Three cycles are shown that have matched combustion phasing, combustion rate, and time of knock onset, but have knock intensity that differs by a factor of six. Thus, the prediction of knock intensity must include a stochastic component. It is shown that there is a relationship between the maximum possible knock intensity and the unburned fuel energy at the time of knock onset. Further, for a small window of unburned energy at knock onset, the probability density function of knock intensity is self similar when scaled by the 95th percentile of the cumulative distribution, and log-normal in shape.

Modeling ignition kernel development in spark ignition engines is crucial to capturing the sources of cyclic variability, both with RANS and LES simulations. Appropriate kernel modeling must ensure that energy transfer from the electrodes to the gas phase has the correct timing, rate and locations, until the flame surface is large enough to be represented on the mesh by the G-Equation level-set method. However, in most kernel models, geometric details driving kernel growth are missing: either because it is described as Lagrangian particles, or because its development is simplified, i.e., down to multiple spherical flames. This paper covers the geometric aspects of kernel development, which makes up the core of a Triangulated Lagrangian Ignition Kernel model. One (or multiple, if it restrikes) spark channel is initialized as a one-dimensional Lagrangian particle thread.

An overview of a design methodology based on finite element and fatigue analyses is described for the design of welded structures. Fatigue life is a primary design consideration for agricultural equipment structural members. The re-design of an agricultural implement frame and hitch assembly is used to illustrate the methodology for optimal design and improved fatigue life. A description of the finite element mode of the agricultural implement and the simulated loading history are described. Results from finite element analysis are used to optimize the frame member sizes and calculate the fatigue strength characteristics. This design analysis strategy provides improved fatigue life characteristics for the implement frame or welded structure.

THIS paper is a sequel of the paper, “Photo-Electric Combustion Analysis,” presented at the 1936 Semi-Annual Meeting of the Society. The indicator described in that paper has been used to study combustion of 28 fuels and chemicals. A complete table of information of the materials used as fuels is included. The results obtained from over 1000 oscillograms show a different shape of ignition-lag curve versus injection advance angle than it is ordinarily thought to have. Even though the cetane values for these 28 fuels varied from 24 to 100, they all had nearly the same ignition lag when injected near the dead-center position. This minimum value is shown to be about 1/1000 sec. The fuels of higher-cetane value reach this minimum at an earlier injection angle than do those of low-cetane value. The paper shows how a high-cetane fuel can be just as rough as a low-cetane fuel if the injection timing is too early.

The results of two derivations relating to the fuel economy of hybrid-electric vehicles (vehicles which employ both a heat engine and electric drive system) are presented and their use is illustrated through the examples of the University of Wisconsin and TRW Systems Group hybrid-electric vehicles. The method of mileage estimation employs a specific fuel-consumption versus torque-speed map for the heat engine under study and knowledge of the hybrid-vehicle dynamics and road-load power. The method is easily extended to estimation of emission reductions through use of specific-emission-production versus torque-speed maps and is applicable to hybrid vehicles with other than electrical energy-storage systems.

AN analysis of phenomena occurring during the ignition delay period is presented. Vaporization of atomized fuel is shown to take place under conditions ranging between single droplet and adiabatic saturation from edge to center of the spray. Mechanisms of vaporization and combustible mixture formation are presented for both cases. Correlation of theoretical analysis with experimental data from both a combustion bomb and diesel engine is presented to establish actual conditions existing during vaporization. Estimates of physical and chemical delays for the engine and bomb are given.

DATA presented in this paper show temperature-time diagrams obtained from mufflers mounted on trucks which were traveling over their regular routes. Using these temperature data, specimens made of possible muffler materials were subjected to laboratory tests. A wide range of possible muffler materials and gas composition were covered in these tests. Results of the tests indicate that under long-run heavy-duty truck service, muffler failure occurs primarily because of high metal temperatures and that coated mild steel showed the most promise of longer muffler life.

The results of both theoretical and experimental studies on the self-ignition of single pure hydrocarbon drops are described. In this work single drops were subjected to air streams heated to such degrees that self-ignition of the drops would occur. Experimental heat and mass transfer parameters, as well as ignition delay data for different fuels and at different operating conditions were obtained. The experimental data were then used in conjunction with boundary layer correlations to evaluate the extent of the ignition delay that is physical (vaporization) and chemical (molecular interaction).

The infrared radiation method of compression and end-gas temperature measurement was applied to the problem of measuring gas temperatures up to the time of knock. Pressure data were taken for each run on a CFR engine with mixtures of isooctane and n-heptane under both knocking and nonknocking conditions. Main engine parameters studied were the intake pressure, intake temperature, and engine speed. The rate and extent of chemical energy release were calculated from the temperature and pressure histories using an energy balance. The computed rates of chemical energy release were correlated to a chain-type kinetic model

A detailed mathematical model of the thermodynamic events of a crankcase scavenged, two-stroke, SI engine is described. The engine is divided into three thermodynamic systems: the cylinder gases, the crankcase gases, and the inlet system gases. Energy balances, mass continuity equations, the ideal gas law, and thermodynamic property relationships are combined to give a set of coupled ordinary differential equations which describe the thermodynamic states encountered by the systems of the engine during one cycle of operation. A computer program is used to integrate the equations, starting with estimated initial thermodynamic conditions and estimated metal surface temperatures. The program iterates the cycle, adjusting the initial estimates, until the final conditions agree with the beginning conditions, that is, until a cycle results.

THIS paper discusses a method of measuring compression temperature by means of the absorption of light. An optical-electronic system measures the change in color of a trace of iodine gas that has been added to the intake mixture. From these measurements the temperature of the iodine and by inference, the temperature of the gases, is determined. The apparatus used is described briefly and the test results obtained in measuring compression and end-gas temperatures in a spark-ignition engine are also presented.

THE PRESENT WORK uses both the hot-motored technique and a nitrogen technique to obtain three pressure-time records — one without either vaporization or chemical reaction, one with vaporization only, and one with both vaporization and chemical reaction. By comparison of these three records, rates of vaporization and rates of chemical reaction can be determined during the ignition delay period in an operating diesel engine. Such data are shown for different fuels and operating conditions. Estimations are made of the penetration and temperatures existing in the spray.*

Fine-wire resistance thermometers were used to measure compression gas temperatures in a motoring (nonfiring) cycle CFR engine. Temperature versus crankangle curves were obtained for the compression and expansion strokes by means of tungsten wires ranging in diameter from 0.15–1.00 mils and at speeds from 600–1800 rpm. The results were compared with the infrared pyrometer; the peak temperature and peak crankangle lags were determined as a function of the wire diameter and engine speed. Attempts to evaluate the instantaneous energy balance around the wire resulted in a negative heat transfer coefficient, for which no current satisfactory explanation is available, although other observers have reported similar phenomena. The tungsten resistance thermometer is simple to build, easy to install, and requires no modification of the engine block for use during motoring. Thus, it is suitable for comparing the compression temperatures of different design engines.

The EcoCAR Mobility Challenge (EMC) is the latest edition of the Advanced Vehicle Technology Competition (AVTC) series sponsored by the US Department of Energy. This competition challenges 11 North American universities to redesign a stock 2019 Chevrolet Blazer into an energy-efficient, SAE level 2-autonomous mild hybrid electric vehicle (mHEV) for use in the Mobility as a Service (MaaS) market. The Mississippi State University (MSU) team designed a P4 electric powertrain with an 85kW (113.99 HP) permanent magnet synchronous machine (PMSM) powered by a custom 5.4 kWh lithium-ion energy storage system. To maximize energy efficiency, Model Based Design concepts were leveraged to optimize the overall gear ratio for the P4 system. To accommodate this optimized ratio in the stock vehicle, a custom offset gearbox was designed that links the PMSM to the rear drive module.

The performance of a structural design significantly depends upon the assumptions made on input load. In order to estimate the input load, during the design and development stage of the suspension assembly of a BAJA car, designers and analysts invest immense amount of time and effort to formulate the mathematical model of the design. These theoretical formulations may include idealization errors which can affect the performance of the car as a final product. Due to the errors associated with the assumption of design load, several components might have more weight or may have less strength than needed. This discrepancy between the assumed input load (lab or theoretical studies) and the actual load from the environment can be eliminated by performing a real life testing process using load recovery methodology. Commercial load cells exist in industry to give engineers insight to understanding the complex real world loading of their structures.

In the current work, a series-hybrid vehicle has been constructed that utilizes a dual-fuel, Reactivity Controlled Compression Ignition (RCCI) engine. The vehicle is a 2009 Saturn Vue chassis and a 1.9L turbo-diesel engine converted to operate with low temperature RCCI combustion. The engine is coupled to a 90 kW AC motor, acting as an electrical generator to charge a 14.1 kW-hr lithium-ion traction battery pack, which powers the rear wheels by a 75 kW drive motor. Full vehicle testing was conducted on chassis dynamometers at the Vehicle Emissions Research Laboratory at Ford Motor Company and at the Vehicle Research Laboratory at Oak Ridge National Laboratory. For this work, the US Environmental Protection Agency Highway Fuel Economy Test was performed using commercially available gasoline and ultra-low sulfur diesel. Fuel economy and emissions data were recorded over the specified test cycle and calculated based on the fuel properties and the high-voltage battery energy usage.