Index-Matching Technique for Effective Liquid Flow Diagnostics for Internal Combustion Engine

An effective technique for visualization and measurement of liquid flows in a model of internal combustion engine (ICE) is presented. The technique is based upon the use of index-controlled fluid and transparent plastic models that have the same index of refraction as the fluid. This index-matching method allows unblocked flow visualization of any locations deep inside the model, locations that could not be observed or illuminated by other techniques. This advantage is enhanced by the use of rapid prototyping in which any complex geometry of the model can be fabricated directly and effectively from 3-D CAD data or 3-D surface data of the model. Some applications of this technique combined with PIV technique are presented.