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Validation of the Ford General Engine SIMulation program (GESIM) with measured firing data from a modified single cylinder Ricardo HYDRA research engine is described. GESIM predictions for peak cylinder pressure and burn duration are compared to test results at idle operating conditions over a wide range of valve overlap. The calibration of GESIM was determined using data from only one representative world-wide operating point and left unchanged for the remainder of the study. Valve overlap was varied by as much as 36° from its base setting. In most cases, agreement between model and data was within the accuracy of the measurements. A cycle simulation computer model provides the researcher with an invaluable tool for acquiring insight into the thermodynamic and fluid mechanical processes occurring in the cylinder of an internal combustion engine.

Feasibility of wall-flow diesel exhaust filter trap particulate aftertreatment emission control systems to meet the U.S. Federal, CARB, and EC passenger car standards for 1997/2003 and beyond for the 1360 kg (3000 lb.) EAO (Ford European Automotive Operations) 1.8 liter Sierra Turbo-Diesel passenger car is investigated. Plain and Pd catalyzed monolith wall flow diesel particulate traps are examined using Phillips No. 2 diesel fuel (Reference Standard), low sulfur (0.05% S) diesel fuel and an ultra-low sulfur (0.001% S) diesel fuel. Comparisons are made with baseline FTP75 and Highway exhaust emissions and Federal and CARB mandated particulate standards for 1997 and 2003. Effectiveness of catalyzed traps, plain traps, copper octoate trap regeneration fuel additive, and fuel sulfur content on the particulate emissions is determined.

A 1.8L turbocharged diesel engine valvetrain friction was investigated, and the effectiveness of using a solid film lubricant (SFL) coating in reducing friction was determined throughout the operable speed range. This valvetrain design features direct acting mechanical bucket valve lifters. Camshaft journal bearing surfaces and all camshaft rubbing surfaces except lobe tips were coated. The direct acting bucket shims were etched with a cross hatch pattern to a depth sufficient to sustain a SFL film coating on the shim rubbing surfaces subjected to high surface loads. The SFL coated valvetrain torque was evaluated and compared with uncoated baseline torque. Coating the cam bearing journal surfaces alone with II-25D SFL reduced valvetrain friction losses 8 to 17% for 250 to 2000 rpm cam speed range (i.e. 500 - 4000 rpm engine speed). When bucket tappet and shims were also coated with the SFL, further significant reductions in coated valvetrain friction were observed.

The development, evaluation, and selection of Plasma spray powder material for the coating of aluminum-alloy engine cylinder block bores was conducted to yield a bore system which provides numerous benefits relative to the present cast iron sleeve system. These include: a reduction in ring/bore wear, friction, and in engine oil consumption as well as a benefit in reduced corrosion. A reduction in engine weight, overall costs, and improvements in machining and honing operations are shown. Alternate thermal spray processes are also described in this investigation. Test evaluation leads to the selection of two plasma powder material spray systems. One system emphasizes low cost relative to the present system. The second system provides significant reduction in friction and ring/bore wear through the introduction of solid lubricant in the material composition.

An extremely tough alumina based ceramic coating produced by a modified anodizing process developed at Moscow Aviation Institute has been evaluated for light weight, wear resistant component applications in automotive powertrain. The process details and test results from comparative evaluation of friction and wear properties for cylinder bore application, referenced to cast iron baseline, are presented and discussed.

Diesel engine particulates collected on a trap cause the exhaust back pressure to increase and adversely affect fuel economy and vehicle performance. Therefore, a trap must be periodically regenerated by oxidizing the collected particulates. Several techniques for regenerating a Diesel particulate trap are discussed. Regeneration was achieved with high speed and high load engine operation. Lead, added to the Diesel fuel, acted as a catalyst and reduced the ignition temperature of particulates collected on a trap by about 300°F. Throttling the intake air flow increased exhaust temperature to facilitate regeneration at moderate vehicle speeds. An externally fueled burner provided regeneration over the widest range of engine operating conditions, including idle.

The potential for catalysts, to operate with leaded fuel, was evaluated by screening catalysts under a variety of steady state and cyclic conditions with 0.4 g/l leaded fuel. The influence of precious metal loading, formulation and the level of inlet O2 was also evaluated. Pure Pt was superior to catalysts containing Pt and Pd. Cyclic aging provided much better catalyst performance retention than steady state exposure. The scavenging effect of HCl and HBr, which accomplishes deposit removal in the combustion chamber, may also operate on the catalyst where cyclic operation assures a proper balance of temperature above and below 550° C.

Advanced techniques for regenerating diesel particulate traps are described. A bypassable trap system minimized regeneration thermal energy requirements. Thermal regeneration systems with burners or electric resistance heaters were evaluated. Regeneration emissions and fuel consumption penalties were measured. Catalytic fuel additives consisting of octoate based compounds of copper and nickel, and copper and cerium provided reductions of up to 410°F in trap regeneration temperature. Durability tests confirmed frequent self regeneration with fuel additives. Over 95% of the fuel additive was collected by the trap. The useful life of the trap having a volume equal to engine displacement was estimated to be 30,000 miles.

Thermal and catalytic techniques for regenerating particulate traps were assessed. The thermal technique used a burner which heated engine exhaust to the ignition temperature of the particulates to achieve over 90% regeneration effectiveness. HC, CO and particulate emissions resulting from combustion of particulates and burner exhaust were 25 to 50% of the allowable vehicle emissions for one CVS cycle. The fuel consumed by the burner was 9% of the fuel consumed by a vehicle over one CVS cycle. Problems with burner nozzle clogging, ignition reliability, trap durability and control system requirements were identified. In the catalytic technique, Diesel fuel containing .5 gm/gal lead and .25 gm/gal copper lowered the ignition temperature of the particulates by 425°F so that periodic regeneration occurred. The trap collected nearly all of the lead and copper resulting in limited trap life, and deposits on the engine fuel nozzles tended to increase HC emissions.