A New Design Methodology of Thermal Barrier Coating (TBC) for Internal Combustion Engines

Abstract

Currently available Internal combustion (IC) engines contribute 25% of the total world energy consumption. IC engines convert only 40% of the fuel energy into the indicated power[1]. Roughly, 30 percent of heat energy is lost from the combustion chamber to the environment. Interest in the design and development of thermal barrier coating (TBC) is increasing due to an increase in fuel costs and due to the decrease in high quality fuel production[2], [3]. The coating materials with low thermal conductivity and high heat capacity led to problems of high surface temperature, which degrade the volumetric efficiency and an increase in the NOx emission. On the other hand, thin TBC of low thermal conductivity and low heat capacity showed high thermal efficiency. Thin coatings could able to prevent intake air heating with effective resistance during the combustion[4]. However, fundamental relationships between thermal efficiency and thermophysical properties, structure, and durability of TBC still need to be investigated. Few studies suggested that the heat interaction study based on the crank angle position could be the best method to estimate the thermodynamics efficiency than the conventionally calculated heat rejection by the adiabatic engine[5], [6]. This work shows a design methodology to develop a thermal barrier coating (TBC), which can reduce heat loss by maintaining the minimum temperature difference between the surface and the in-cylinder gas temperature. The temperature fluctuation of TBC improves the thermal efficiency of internal combustion (IC) engines by reducing the heat loss to the coolant. This work also investigates the thermophysical behaviour of nearby available material and the applicability as a TBC.