Investigation of chemical heat storage processes for recovering exhaust gas energy in internal combustion engines

© 2018 Australasian Fluid Mechanics Society. All rights reserved. Improving the energy efficiency of the IC engine and hybrid vehicles has become more and more important. Chemical heat storage system is one of the approaches to address it by utilising the wasted energy. This study was aimed to develop a chemical heat storage (CHS) system using magnesium hydroxide (Mg(OH)2) to recover the thermal energy wasted by the exhaust gas in internal combustion (IC) engines. The stored heat can be used to heat the intake air, catalysts, lubricants in IC engines and batteries in hybrid vehicles. Experiments were conducted on a diesel engine (D1146TI) to estimate the efficiency of CHS technology in the heat storage process. Experimental results showed that at engine load 60% to 80%, 33.68% to 61% of the chemical material reacted with 3.69% to 5.05 % heat energy of exhaust gas stored in one hour time. The percentages of the reacted chemical material and the stored exhaust gas heat energy decreased with the decreased engine load