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Optimizing heat protection for underbody and underhood components, using non-CFD heat transfer CAE tools, requires the estimation of local convective heat transfer coefficients. This estimate, in turn requires knowledge of the local air velocity. Currently available methods for obtaining this velocity at several vehicle locations have been impractical and expensive for use in over-the-road testing. This paper presents the design, fabrication, and field testing results of a 26 mm diameter spherical transducer which measures the local heat transfer coefficient directly. The transducer contains three thermocouples and a heater. It is calibrated to correlate the coefficient with the air velocity. Drawing less than 0.1 A, a number of them can be powered by the vehicle battery with negligible drain. The data acquisition consists of sampling three thermocouples per spherical transducer.

The impingement of air jets on a vehicle's windshield is one parameter that determines the effectiveness of the defroster's system in freeing the windshield of frost and fog. Incompressible air jets impinge upon the inner surface of the windshield and create hydrodynamic and thermal boundary layers which in turn control convective heat transfer. Therefore, understanding the heat transfer interaction between impinging air jets and an inclined windshield is of practical relevance. Experimental investigations on the temperature distribution are performed on the inner surface of the windshield for the purpose of obtaining local and average heat transfer coefficients. In this paper, the temperature distribution of a vehicle's windshield is investigated using liquid crystals. As a result, a temperature contour map is generated displaying local temperature values on the inner surface of the windshield.

Engine experiments were conducted on a heavy-duty single-cylinder engine to explore the effects of charge preparation, fuel stratification, and premixed fuel chemistry on the performance and emissions of Reactivity Controlled Compression Ignition (RCCI) combustion. The experiments were conducted at a fixed total fuel energy and engine speed, and charge preparation was varied by adjusting the global equivalence ratio between 0.28 and 0.35 at intake temperatures of 40°C and 60°C. With a premixed injection of isooctane (PRF100), and a single direct-injection of n-heptane (PRF0), fuel stratification was varied with start of injection (SOI) timing. Combustion phasing advanced as SOI was retarded between -140° and -35°, then retarded as injection timing was further retarded, indicating a potential shift in combustion regime. Peak gross efficiency was achieved between -60° and -45° SOI, and NOx emissions increased as SOI was retarded beyond -40°, peaking around -25° SOI.

A computer program which rapidly calculates the equilibrium mole fractions and the partial derivatives of the mole fractions with respect to temperature, pressure and equivalence ratio for the products of combustion of any hydrocarbon fuel and air is described. A subroutine is also given which calculates the gas constant, enthalpy, internal energy and the partial derivatives of these with respect to temperature, pressure and equivalence ratio. Some examples of the uses of the programs are also given.

Development status and insight on a “research level” piezoelectric direct injection fuel injection system for prototype hydrogen Internal Combustion Engines (ICEs) is described. Practical experience accumulated from specialized material testing, bench testing and engine operation have helped steer research efforts on the fuel injection system. Recent results from a single cylinder engine are also presented, including demonstration of 45% peak brake thermal efficiency. Developing ICEs to utilize hydrogen can result in cost effective power plants that can potentially serve the needs of a long term hydrogen roadmap. Hydrogen direct injection provides many benefits including improved volumetric efficiency, robust combustion (avoidance of pre-ignition and backfire) and significant power density advantages relative to port-injected approaches with hydrogen ICEs.

Several emission performance tests like Butane Working Capacity (BWC), Cycle Life, and ORVR load tests are required for the certification of a vehicle; these tests are both expensive and time consuming. This paper presents a test process based upon analytical simulation of BWC of an automotive carbon canister in order to greatly reduce the cost incurred in physical tests. The computational model for the fixed-bed system of a carbon canister is based upon non-equilibrium, non-Isothermal, and non-adiabatic algorithm to simulate the real life loading/purging of hydrocarbon vapors from this device.

The introduction of carburetor restrictor plates in NASCAR racing in 1988 necessitated the redesign of some engine components, such as the camshaft and exhaust headers, to re-optimize engine performance. This paper describes how an engine performance computer simulation code was used to quickly study the effects of the restrictor plate on the “breathing” processes of the Ford NASCAR V8 engine and determine the optimal intake and exhaust cam lobe profiles to maximize wide-open throttle torque and horsepower. The resulting camshaft design produced over 40 additional horsepower and greater average torque over the useful engine speed range for super speedways. The interaction between exhaust wavedynamics (i.e., “tuning”) and cam events was investigated and shown to be of critical importance to the optimization of the engine's trapping efficiency.

This book presents an analysis on the potential effects of globalization on the automotive industry and the environment. Energy challenges, market economy growth, and population dynamics are considered. The authors also present future scenarios for transportation technologies to meet the ever growing global demand for transportation of goods and services while minimizing energy and environmental impacts and maximizing cost, value and widespread acceptance.

A new diesel engine, called the 6.7L Power Stroke® V-8 Turbo Diesel, and code named "Scorpion," was designed and developed by Ford Motor Company for the full-size pickup truck and light commercial vehicle markets. The combustion system includes the piston bowl, swirl level, number of nozzle holes, fuel spray angle, nozzle tip protrusion, nozzle hydraulic flow, and nozzle-hole taper. While all of these parameters could be explored through extensive hardware testing, 3-D CFD studies were utilized to quickly screen two bowl concepts and assess their sensitivities to a few of the other parameters. The two most promising bowl concepts were built into single-cylinder engines for optimization of the rest of the combustion system parameters. 1-D CFD models were used to set boundary conditions at intake valve closure for 3-D CFD which was used for the closed-cycle portion of the simulation.

The development of an integrated Perforated Manifold, Muffler, and Catalyst (PMMC) for an automotive engine exhaust system is described. The design aims to reduce tailpipe emissions and improve engine power while maintaining low sound output levels from the exhaust. The initial design, based on simplified acoustic and fluid dynamic considerations, is further refined through the use of a computational approach and bench tests. A final prototype is fabricated and evaluated using fired engine dynamometer experiments. The results confirm earlier analytical estimates for improved engine power and reductions of emissions and noise levels.

Several types of hybrid-electric vehicles have been developed at Ford Research Laboratory. Among the parallel hybrid systems with a single electric motor, two types were studied. In the first type, the electric motor was attached directly to the crankshaft (mild hybrid) [1], to enable the engine start-stop and regeneration functions. In the second type (full hybrid) the electric motor was connected to the engine through the use of a clutch to allow electric launch of the vehicle and pure electric driving at low speeds. The full hybrid powertrain described in this paper uses a more powerful electric motor for enhanced regenerative braking and engine power assist. An engine-disconnecting clutch saves energy during both the electric propulsion and during vehicle braking. When the clutch is disengaged the engine is shut-off, which eliminates the energy otherwise spent on motoring the engine during electric propulsion.