Energy Storage in Diesel Engine using Alumina PHE in Waste Heat Recovery System Benjamin Franklin S*, Ramesh K** *Department of Mechanical Engineering, Sri Ramakrishna Institute of Technology, Coimbatore, India. franklinshee@yahoo.co.in **Department of Mechanical Engineering, Government College of Technology, Coimbatore, India Online published on 23 March, 2017. Abstract Energy storage of alumina pebble bed heat exchanger with compressed air has been experimentally investigated compared with PHE fitted in single cylinder water cooled diesel engine exhaust air and compressed air. The pebble bed heat exchanger is used to engine exhaust pipe. The experimental set up consists of pebbles are randomly dumped and packed in a 450 mm long hollow tube and 45 mm inner diameter. The diameters of alumina spheres varied from 4 to 10 mm. The tube was insulated from outside to minimize radial heat loss. Hot air from a source was allowed to flow into the packed bed at various inlet conditions of velocity varying from 3 to 6 m/s and temperatures ranging from 305ºC. The spheres were heated from an initial temperature of 30ºC to near steady state conditions. K- Type thermocouples were used to sense temperatures. The porous media temperatures, engine exhaust gas temperature and energy saved at various loads were investigated. Compressed air with engine exhaust air using pebble bed heat exchanger was compared. Energy was stored in waste heat recovery system. The PMT, engine exhaust gas temperature and energy storage were higher in the engine exhaust air with compressed air using PHE. Top Keywords Waste heat recovery, Heat exchanger, Heat transfer, Porous media, Alumina pebbles. Top |