Authors: Eduardo José Cidade Cavalcanti
Addresses: Faculty of Mechanical Engineering, Federal University of Rio Grande do Norte, 59072-970 Natal/RN, Brazil
Abstract: This research presents the effects of exhaust gas recirculation (EGR) and load on a diesel engine. The operational conditions of diesel engine were different loads (5-30 kW) with increment of 5 kW and EGR rate (0-10%) with increment of 2.5%. The engine was supplied with blend of diesel and 7% of biodiesel. The exergetic, exergoeconomic and environmental analysis were investigated in order to evaluate the cost and pollutant emissions of electricity. The results reveal that the load increases the exergetic efficiency, exergy destruction, fuel cost rate and reduces the specific power cost and relative cost difference. In addition, the EGR rate decreases the exergetic efficiency and increases exergy destruction, fuel cost rate, relative cost difference and specific power cost. At low load, the specific total pollution damage is predominant, then the higher EGR rate is desired. At high load, reduction of performance is significant with EGR rate, and total pollution damage loses significance, then the lower EGR rate is desired. Therefore, the maximum load and EGR rate of 2.5% are the best condition under the exergoeconomic and environmental point of view.
Keywords: diesel engine; exergoeconomy; environmental; exhaust gas recirculation; EGR; emissions; exergy; experimental data; combustion reaction; unburned hydrocarbon; unit damage cost; engine load; constant speed.
International Journal of Exergy, 2019 Vol.29 No.1, pp.22 - 42
Received: 28 Aug 2018
Accepted: 25 Jan 2019
Published online: 10 May 2019 *