Experimental studies on heat recovery from diesel engine exhaust in packed pebble bed heat exchanger and thermal energy storage using phase change materials

Abstract

The exhaust gas from diesel engine incorporates away approximately 30% of the combustion heat. The energy obtained in many energy conversion devices is wasted if no longer used well. The fundamental technical constraint that stops efficaciously of waste heat recuperation is due to its intermittent and time mismatched demand and availability of energy. In the present work, a Packed Pebble Bed Heat Exchanger is incorporated with an internal combustion engine setup to extract heat from exhaust gas and also a thermal energy storage (porous media) is used to store the excess power. A combined sensible and latent heat storage system is designed, fabricated and examined for thermal energy storage with the use of cylindrical phase exchange materials. The pebble bed heat exchanger is full of the bulk substances contains round pebbles and can operate at an excessive temperature to heat and cool gaseous media. The thermal power storage is that inventory to secure the energy by heating or cooling of storage medium so that the saved energy can be used at a later time for heating and cooling applications. Packed beds have been used considerably in engineering processes along with filtration, heat and mass storage, industrial stripping and catalysis. A packed bed is outlined as a variety of particles drop into a container. The particles form a matrix-like structure which contain voids or pores wherein fluid is free to percolate. A packed column is a specific case in which the packed bed is limited interior a cylindrical tube. The packed column can either be fixed or fluidized. A fluidized bed is the phenomena when the particles are in motion, excited by using the flow of fluid therefore capable of following the random nondeterministic movement of the fluid. In this work, it is only concerned with the design of fixed beds, their geometric properties and their impact at the flow newline