A Thermoelectric System for Emission Control Optimization in Two-Wheeler Automotive Applications

Environmental pollution is one of the growing concerns of our society. As vehicle emissions are a major contributor to air pollution, emission control is a primary goal of the Automotive industry. Vehicle emissions are higher due to improper combustion, which leads to toxic gases being generated from the exhaust system. Unburnt fuel is one of the leading causes of toxic pollutants such as Carbon Monoxide, Nitric Oxides (NOx) and Hydrocarbons. The catalytic converter converts these gases into less toxic substances such as Carbon Dioxide, Nitrogen, and water vapor. The catalytic converter performs efficiently after reaching its “Light Off” temperature, after which the catalyst becomes active. Hence, elevated temperature of the exhaust gases aids in efficient conversion. Presently, the gases from the exhaust system are approximately at a temperature of 300°C-600°C. This paper outlines the concept of a Peltier (Thermoelectric) Module - based system, which helps maintain the high temperature of the exhaust gases prior to entering the catalytic converter. Peltier Modules are thermoelectric devices well-known for their usage in heating/cooling applications. The proposed system includes a chamber in which the Peltier Module is embedded. As the gases flow through the chamber, the embedded Peltier Module, which is powered by the battery, increases the temperature inside the chamber. Therefore, with this concept, the components required to heat the catalytic converter could be potentially reduced, since the exhaust gases will be maintained at the targeted temperature required for better emission control. Moreover, the Peltier Module is also known to be used for electricity generation. Consequently, by generating electricity through heat utilization on the surface of the chamber, we provide an added benefit of this proposed concept. This can be achieved by mounting the Peltier Module on the hot surface of the chamber. The other side of the Peltier Module is exposed to ambient air and thereby a potential difference is created through the Seebeck Effect.