الفهرس 
CONCLUSIONS AND RECOMMENDATIONSOnly 14 pages are availabe for public view
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Abstract
This thesis investigates and demonstrates a technique for reducing particles from exhaust
gas recirculation (EGR). The method relies on the principle of Brownian diffusion of
particles and molecules.
Diffusion coefficients for molecules such as CO2, H20 and O2 are several orders of
magnitude higher than for typical exhaust particles. Therefore, a clean air stream of an
engine intake air, passing next to an exhaust stream, portioned by a perforated tube, should
become enriched with exhaust - derived CO2, H20 and deprived of oxygen via molecular
diffusion while exhaust - derived particle diffusion to clean air stream will be insignificant.
In essence, gas phase equilibrium between the exhaust stream and clean air stream is
reached in a relatively short time, while particle phase equilibrium is relatively slow.
To explore this phenomenon, a particle-free EGR exchanger (PF-EGR-E) was fabricated.
The exchanger is a shell and tube type made of copper with perforated tube section.
A portion of the exhaust gas is recirculated to the engine intake through a pressure
pulsation tank. Exhaust gas is the tube fluid and intake air is the shell fluid. Volume flow
rates for both exhaust and intake air are controlled to be equal at different flow rates.
The experiment was performed for four engine speeds: 900, 1200, 1500 and 1800 rpm. At
each speed the tests were performed at no-load, half-load and full-load conditions.
Different EGR percentages were applied on each load condition ranging from 0% EGR to
20% EGR. Measurements for NOx, HC, CO2, O2, CO and PM were recorded upstream and
down stream the (PF-EGR-E).