Abstract
Keywords EGR-cooler, homologation, Exhaust gas recirculation, experimental tools, diesel.
Abstract - EGR-cooler is a crucial component inside the whole EGR system in diesel engines with the aim of accomplishing pollutant emissions policies. EGR-coolers are recent components in vehicle manufacturing industry that need homologation to test their reliability.
An EGR-cooler is a gas-liquid cooler that decreases exhaust gas temperature through heat transfer to the refrigeration liquid. So, the processes in which EGR-cooler is involved impose very rigorous design and homologation requirements.
In this paper, different homologation tests and tools for EGR-cooler out-of-engine are presented regarding different critical aspects of this component. In this way, there are presented different types of test: Fatigue tests, including thermal ones, pressure inside the cooler and vibrations, which consists of hardening working conditions; requirement evaluation tests, which are efficiency and pressure drops, linked with the needs that the component should accomplish. There are also presented special features tests, for example bubbles, where the coolant behaviour inside the cooler are analysed; and corrosion, where the problem of hot corrosion due to the acids contained in the exhaust gases is studied.
Different testing facilities have been developed to accomplish the different tests proposed, being these facilities presented with their capabilities. There are also presented different experimental results of the different tests.
Finally, a methodology to homologate this type of components is proposed.