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This paper describes the simulation-driven design process used in engines technology. The research question is “how to use research in the structural analysis and dynamics field to ensure world-class product development?” This paper describes research on simulation methodologies from the design process perspective, demonstrating the need for research in various steps of product development. Each section of the paper includes one or two practical examples in which research was needed to increase product design quality. In the product definition section, the Digital Design Platform (DDP) shows the coupling between product requirements and simulation tasks. At the concept design stage, it is shown that computational methods can optimize the placement of material in the case of the main bearing cap topology.

The roller brake dynamometer (RBD) is used to measure and evaluate the braking efficiency of road vehicles in periodic technical inspections (PTI). The quality of roller brake dynamometers is very important, to ensure adequate reliability of the periodic technical inspection and to ensure the road safety of motor vehicles. It is known that dynamometer measurements involve a large number of uncertainties. The brake force measurement covers the force mechanism, sensors, data acquisition, measuring and calculation programmes, roller diameters, friction surface, and calibration of the roller brake dynamometer. At the level of the ECE-13 regulations, the quality requirements and calibration methods are not specified. The Motor Vehicle Administration in Finland is running a project to develop quality requirements and calibration methods for roller brake dynamometers. The aim is to improve the reliability and to reduce the standard deviation at inspection stations and brake workshops.

The distribution of the braking forces between axles has influence to the vehicle's braking ability, braking behaviour, and safety in traffic. In designing of brakes it is important to meet the most essential demands which are operating environment, structural properties of a vehicle, basic dimensioning of the brake mechanisms, and the controllability of braking forces as well as regulations on brakes. This paper introduces a study of the results during braking of 2- and 3-axle lorry and concentrates on the fulfilment of the braking force distribution according to the regulations in Finland. The friction requirements are compared with the regulations.

Heavy lorries and trailer combinations cause many serious traffic accidents. There in Finland alone have been approximately100 killed per year by heavy duty vehicles in 1990's. Improvements in inspection methods of brake systems increase traffic safety. In Finland dynamometer measurements have been used since 1960´s, and its advantages are stable measuring conditions, high repetability and short inspection time. The Finnish Traffic Office and the Finnish Motor Vehicle Registration Centre have been interested in correlations of road retardation and dynamometer measurements and therefore established Dynamet-brake research project in 1993. This paper contains a research which aims to find out correlations of retardation prediction for lorries and trailer combinations by comparing road braking tests and dynamometer measurements, and secondly to improve the dynamometer measurement system at inspection stations.

Heavy lorries and trailer combinations cause many serious traffic accidents. Improvements in inspection methods of brake systems increase traffic safety. In Finland dynamometer measurements have been used since 1960's, and its advantages are stable measuring conditions, high repetability and short inspection time. Braking force on the wheel periphery generated by the wheel brakes is measured in the roll set of the dynamometer with the help of a power measurement device connected to it. In the vehicle inspection and in the brake repair shops, the estimation of the braking ability of vehicles based on calculated definitions of the performance of the brakes and the retardations to be achieved carried out on the basis of braking forces measured with the dynamometer. The Finnish Ministry of Transport and Communications and the

The function of the metallic after-market catalyst developed by Kemira Oy has been tested in Finnish urban traffic and at the temperatures of various seasons. The test cars had different fuel systems: one was a normal carburettor version and the other was of a multipoint fuel injection type. A simulated drive in an average Finnish town has been used as the driving speed cycle. The driving tests were performed in the cold room laboratory of Neste Oy. The US-83 standard test was performed in the engine laboratory of Kemira Oy for comparison. The results indicate that the function of the catalyst under all driving conditions is more effective when the fuel system is improved. The light-off of the catalyst takes place in less than three minutes, irrespective of the temperature. The scavenging effect of the catalyst is improved by its ability to adsorb components from the exhaust gas, which have not lit-off, also during the rich mixture phase.