5 research outputs found
A study of the effects of the properties of fuel, compression ratio and EGR on diesel exhaust soot physiochemical characteristics
This research work characterises diesel engine soot physiochemical properties and engine performance and emissions for the combustion of two common mineral diesel fuels (low and medium sulphur) and a RME B100 biodiesel fuel at two geometric compression ratios (19.5:1 and 16.5:1) and a broad range of EGR (10 to 55%) for an otherwise unmodified VW 1.9TDI 130PS engine. The principal focus of the research is the physiochemical characterisation of soot sampled from the engine exhaust manifold and also a DPF in the exhaust and exploring how the fuel type, compression ratio and EGR influence the soot properties and how these properties then influence the evolution of the soot in the exhaust. [Continues.
Modelling of vehicle interior noise at reduced scale
The present paper describes some recent results on the development of simplified reduced-scale models that can be
used for experimental studies of vehicle interior noise. In many important cases such simplified structural models
can be described analytically, thus providing a developer with the effective engineering tools for prediction and
mitigation of vehicle interior noise, especially on a design stage. The general approach is illustrated by a 1:4-scale
simplified model of a car developed at Loughborough University – 'QUASICAR' (QUArter –Scale Interior Cavity
Acoustic Rig). The model consists of a curved steel plate that is simply supported by two rigid side walls made of
massive wooden panels. The effect of road irregularities exciting vehicle structural vibrations is imitated by
electromagnetic shakers applied to the bottom of the steel plate. Measurements of structural vibrations and of the
acoustic pressure generated inside the model are compared with the results of theoretical predictions
Investigation of structural-acoustic coupling in a thin-walled reduced-scale model of a car
The present paper describes the results of the recent research into simplified reduced-scale thin-walled
models that can be used for experimental studies of vehicle interior noise. In many important cases
such models can be described analytically, thus providing a developer with the effective engineering
tools for prediction and mitigation of vehicle interior noise, especially on a design stage. The
structural simplification in the models is based on understanding the physics of generation of
predominant modes of structural vibrations by particular dynamic forces and of radiation of sound by
the excited vibrations into the vehicle interior. The above-mentioned general approach is illustrated by
a 1:4-scale simplified physical model of a car developed at Loughborough University – 'QUASICAR'
(QUArter –Scale Interior Cavity Acoustic Rig). The model consists of a curved steel plate that is
simply supported by two rigid sidewalls made of massive wooden panels. The effect of road
irregularities exciting vehicle structural vibrations is imitated by electromagnetic shakers applied to the
bottom of the steel plate. Measurements of structural vibrations and of the acoustic pressure generated
inside the model at different positions demonstrate their good conceptual agreement with the results of
theoretical predictions
Finite element calculations of structural-acoustic modes of vehicle interior for simplified models of motorcars
The present paper describes the results of finite element analysis of structural
vibration modes, interior acoustic modes, and structural-acoustic modes in some simplified models of
road vehicles having different levels of complexity, in particular in the QUArter-Scale Interior Cavity
Acoustic Rig (QUASICAR) developed in Loughborough University. All the analysis has been carried
out using the original code that had been developed in Patran Command Language (PCL) specifically
for the purpose of this research. Resonant frequencies and spatial distributions of structural and
acoustic modes have been calculated initially separately and then taking into account structuralacoustic
interaction. The results have been compared with the experimental data obtained for
QUASICAR. The comparison has demonstrated good agreement between numerical calculations and
experimental results. The developed approach is reliable and efficient, and it can be extended to more
complex vehicle models, thus assisting in better understanding of vehicle interior noise
Finite element analysis of structural-acoustic interaction in simplified models of road vehicles
Finite element analysis of structural-acoustic interaction in simplified models of road vehicle