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In electric fuel injection (EFI) systems the intake air pressure is used as system load signal for calculating injection and ignition parameters together with engine speed. Part of an EFI system for motorcycles is a throttle body module with integrated pressure sensor. As motorcycle systems require smaller components than automotive applications the target for engineering is to minimize the component size and still fulfill other system requirements. Therefore the pressure sensor sampling point should be as close as possible to the throttle shaft to reduce the module size but with a sufficient distance to avoid signal distortion by unsteady flow. This paper describes how to find a suitable sampling position by combining static bench testing, dynamic vehicle testing and CFD analysis.

In new exhaust system specifications such as single cylinder balancing, closed coupled catalyst systems, sensor locations close to the engine, turbo applications, fast light off situations and diesel engine applications the dynamic behavior of the lambda sensor becomes more important. This demands a detailed knowledge and modeling of the relevant parameters. In former analysis of exhaust gas sensors the main focus has been the electrochemical processes in the sensor. The influence of flow structure and protection tubes had lower priority. In this paper we present the numerical and experimental analysis of cold air flowing in a pipe including mounted exhaust sensors. Two double-protection tubes from the Robert Bosch GmbH have been examined named (a) and (b). The predicted results have been compared with values measured with Laser Doppler Anemometry (LDA). The flow pattern in the protection tube type (a) depends on the geometric configuration of the sensor element and the tubes.