Exhaust Catalyst

exhaust catalyst

The exhaust catalyst or catalytic converter for cleaning up exhaust gas was invented by Eugene Houdry (1956), probably best known for inventing a process for cracking crude oil. Two-Way Catalyst 2CO + O2 -> 2CO2 CxH2x+2 + [(3x+1)/2]O2 -> xCO2 + (x+1)H2O Three-Way Catalyst A pollution control device which reduces all three noxious substances: HC, … Read more

Flow Noise

A term generally used to describe aerodynamic noise produced when a gas flows within a duct or when the gas exits the duct, hence flow noise. This is a typical problem observed in the exhaust systems of internal combustion engines and high engine rotational speeds and hence high gas flow rates. There is a balance … Read more

Acoustic Filter Elements

There are a number of different ways to attenuate the sound waves propagating down a duct (eg air intake, exhaust system) and I thought it would be good to list these different acoustic filter elements, how they work and their effect on the sound waves. Absorptive Duct Absorption within ducts is used to break up … Read more

Exhaust System Design

Exhaust system design is primarily about managing the gases ejected from an engine as waste products are transported away from the engine using an exhaust system. The main features that must be considered are: Acoustic design – Acoustic Ducts, Acoustic Filter Elements (eg Silencer), Flow Noise, Shell radiated noise Construction and manufacturing process Durability Dynamic … Read more