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This paper presents an approach to simulating wear on both contact surfaces at the pad-to-rotor interface in disc brakes using general purpose finite element software. It represents a first step toward a method of simulating the brake pressure needed to effectively clean the rotor of unwanted oxide layers. Two simulation cases are presented. The first addresses running-in wear under constant load and corresponds to repeated brake applications at the same constant brake load. The second studies what will happen if a lower load is applied after the contact surfaces have been run-in at a higher load level. This lower load is applied to wear off an oxide layer after a sequence of repeated stop braking at higher load levels.

Flow-through diesel oxidation catalysts (DOC's) have been shown to be an effective means of reducing emissions from diesel engines. In this work, the further development of diesel oxidation catalysts for the control of emissions from heavy duty engines is illustrated. Laboratory reactor and engine dynamometer data obtained from engine-based accelerated poisoning and aging studies demonstrate that HC, CO and SO2 oxidation by DOC's can be modified by adjusting platinum and vanadium loadings in alumina-based Pt/V catalyst formulations. The performance and durability of this type of catalyst system are demonstrated with several aging cycles on heavy-duty engines. The fresh performance of two catalyst systems was determined on both US Heavy Duty Transient and ECE-R49 Test cycles with a 1991 calibration Perkins Phaser 6.0 L engine. Gas phase emissions were reduced by a similar amount for both catalysts over both cycles (HC: 60-70%, CO: 45-75%).