Engine Instrumentation
Overview
A LabView based package has been developed for the post-processing of engine pressure data. Currently LabView hardware and software is being used to give real time analysis of IMEP and its Coefficient of Variation on a rolling basis. This enables the operating point to be selected, so that the system can then record up to 16 channels of data for subsequent post-processing.
A fully digital CCD system has been devloped to grab images on a once-per-cycle basis; this can be used in two ways:
- Looking at the same crankangle on successive cycles, in order to study cycle-by-cycle variations in combustion.
- Constructing a library of images from different crankangles, so that an animation can be constructed. A control system allows us to specify the number of images from each crankangle, and the increments, thus enabling us to select representative cycles for the animation.
The results are being analysed in terms of burning velocity, and the estimation of temperature and soot concentration from a 'three colour' method. Alternatives to measuring crankshaft speed fluctuations are being investigated as a means of estimating the IMEP. Fast response surface thermocouples are being used to measure the combustion chamber surface temperature. By solving the transient heat flow equations, the instantaneous heat flux at each location can be determined on a cycle-by-cycle basis.
Equipment
The Oxford-Rover K4 Engine
Engine control panel and data acquisition system
Last modified 13 July 2007 by WEBNOBODY.