Waste heat recovery from the exhaust of a diesel generator using Rankine Cycle

Abstract Exhaust heat from diesel engines can be an important heat source to provide additional power using a separate Rankine Cycle (RC). In this research, experiments were conducted to measure the available exhaust heat from a 40 kW diesel generator using two ‘off-the-shelf’ heat exchangers. The effectiveness of the heat exchangers using water as the working fluid was found to be 0.44 which seems to be lower than a standard one. This lower performance of the existing heat exchangers indicates the necessity of optimization of the design of the heat exchangers for this particular application. With the available experimental data, computer simulations were carried out to optimize the design of the heat exchangers. Two heat exchangers were used to generate super-heated steam to expand in the turbine using two orientations: series and parallel. The optimized heat exchangers were then used to estimate additional power considering actual turbine isentropic efficiency. The proposed heat exchanger was able to produce 11% additional power using water as the working fluid at a pressure of 15 bar at rated engine load. This additional power resulted into 12% improvement in brake-specific fuel consumption (bsfc). The effects of the working fluid pressure were also investigated to maximize the additional power production. The pressure was limited to 15 bar which was constrained by the exhaust gas temperature. However, higher pressure is possible for higher exhaust gas temperatures from higher capacity engines. This would yield more additional power with further improvements in bsfc. At 40% part load, the additional power developed was 3.4% which resulted in 3.3% reduction in bsfc.

[1]  Marcelo C. Algrain,et al.  Diesel Engine Electric Turbo Compound Technology , 2003 .

[2]  Dimitrios T. Hountalas,et al.  Recovering Energy from the Diesel Engine Exhaust Using Mechanical and Electrical Turbocompounding , 2007 .

[3]  Adnan Parlak,et al.  The effect of thermal barrier coating on a turbo-charged Diesel engine performance and exergy potential of the exhaust gas , 2005 .

[4]  Dimitrios T. Hountalas,et al.  Potential for Improving HD Diesel Truck Engine Fuel Consumption Using Exhaust Heat Recovery Techniques , 2010 .

[5]  Christos Katsanos,et al.  Improvement of bottoming cycle efficiency and heat rejection for HD truck applications by utilization of EGR and CAC heat , 2012 .

[6]  M. Hosoz,et al.  Performance evaluation of an integrated automotive air conditioning and heat pump system , 2006 .

[7]  G P Purohit,et al.  WASTE HEAT RECOVERY IN TRUCK ENGINES , 1978 .

[8]  S. K. Wang,et al.  A Review of Organic Rankine Cycles (ORCs) for the Recovery of Low-grade Waste Heat , 1997 .

[9]  A. Huzayyin,et al.  Experimental evaluation of Diesel engine performance and emission using blends of jojoba oil and Diesel fuel , 2004 .

[10]  J. Larjola,et al.  Electricity from industrial waste heat using high-speed organic Rankine cycle (ORC) , 1995 .

[11]  Mingtian Xu,et al.  The application of field synergy number in shell-and-tube heat exchanger optimization design , 2009 .

[12]  Masayasu Hatazawa,et al.  Performance of a Thermoacoustic Sound Wave Generator driven with Waste Heat of Automobile Gasoline Engine. , 2004 .

[13]  Agostino Gambarotta,et al.  Internal Combustion Engine (ICE) bottoming with Organic Rankine Cycles (ORCs) , 2010 .

[14]  Mehmet Kanogˇlu,et al.  Performance characteristics of a Diesel engine power plant , 2005 .

[15]  M. Canakci,et al.  Combustion characteristics of a turbocharged DI compression ignition engine fueled with petroleum diesel fuels and biodiesel. , 2007, Bioresource technology.

[16]  Syed M. Zubair,et al.  Second-law-based performance evaluation of cooling towers and evaporative heat exchangers , 2007 .

[17]  Saiful Bari,et al.  Waste heat recovery using shell and tube heat exchanger from the exhaust of an automotive engine , 2010 .

[18]  J. P. Holman,et al.  Experimental methods for engineers , 1971 .

[19]  S. Kakaç,et al.  Heat Exchangers: Thermal Hydraulic Fundamentals and Design , 1985 .

[20]  Antonio García,et al.  HD Diesel engine equipped with a bottoming Rankine cycle as a waste heat recovery system. Part 1: Study and analysis of the waste heat energy , 2012 .

[21]  Peter Prenninger,et al.  Charging the Internal Combustion Engine , 2007 .

[22]  Dimitrios T. Hountalas,et al.  Potential Benefits in Heavy Duty Diesel Engine Performance and Emissions from the Use of Variable Compression Ratio , 2006 .

[23]  Dimitrios T. Hountalas,et al.  Study of available exhaust gas heat recovery technologies for HD diesel engine applications , 2007 .

[24]  D. Tennant,et al.  The Turbocompound Diesel Engine , 1989 .

[25]  Willard W. Pulkrabek,et al.  Engineering Fundamentals of the Internal Combustion Engine , 1997 .

[26]  S. Jayaraj,et al.  Performance and emission evaluation of a diesel engine fueled with methyl esters of rubber seed oil , 2005 .

[27]  Octavio Armas,et al.  Effect of biodiesel fuels on diesel engine emissions , 2008 .

[28]  Saiful Bari,et al.  Effect of Different Working Fluids on Shell and Tube Heat Exchanger to Recover Heat from Exhaust of An Automotive Diesel Engine , 2011 .

[29]  Saiful Bari.  Investigation Into the Deteriorated Performance of Diesel Engine After Prolonged Use of Vegetable Oil , 2004 .

[30]  Gerhard Regner,et al.  Waste Heat Recovery of Heavy-Duty Diesel Engines by Organic Rankine Cycle Part I: Hybrid Energy System of Diesel and Rankine Engines , 2007 .

[31]  Ashok Misra,et al.  Parametric optimization and performance analysis of a regenerative Organic Rankine Cycle using R-123 for waste heat recovery , 2012 .

[32]  F. Kreith,et al.  Principles of heat transfer , 1962 .

[33]  Valerie H. Johnson,et al.  Heat-Generated Cooling Opportunities in Vehicles , 2002 .

[34]  K. Srinivasan,et al.  Analysis of exhaust waste heat recovery from a dual fuel low temperature combustion engine using an Organic Rankine Cycle , 2010 .

[35]  Christos Katsanos,et al.  Thermodynamic analysis of a Rankine cycle applied on a diesel truck engine using steam and organic medium , 2012 .

[36]  Richard Stobart,et al.  Thermal efficiency improvement in high output diesel engines a comparison of a Rankine cycle with turbo-compounding , 2010 .

[37]  K. N. Sheeba,et al.  Performance, emission and combustion characteristics of biodiesel fuelled variable compression ratio engine , 2011 .

[38]  John B. Heywood,et al.  Automotive engines and fuels: A review of future options , 1981 .

[39]  Minggao Ouyang,et al.  Study of working fluid selection of organic Rankine cycle (ORC) for engine waste heat recovery , 2011 .

[40]  Yunus A. Cengel,et al.  Fundamentals of thermal-fluid sciences , 2001 .

[41]  M. J. Moran,et al.  Fundamentals of Engineering Thermodynamics , 2014 .

[42]  J. E. Ahern,et al.  The exergy method of energy systems analysis , 1980 .

[43]  Alireza Bahadori,et al.  Simple method for estimation of effectiveness in one tube pass and one shell pass counter-flow heat exchangers , 2011 .

[44]  N. Usta.  An experimental study on performance and exhaust emissions of a diesel engine fuelled with tobacco seed oil methyl ester , 2005 .

[45]  N. B. Elsner,et al.  Performance of the 1 kW thermoelectric generator for diesel engines , 1994 .

[46]  Pan Chu,et al.  Design and optimization of heat exchangers with helical baffles , 2008 .

[47]  Zhen Lu,et al.  Performance analysis and optimization of organic Rankine cycle (ORC) for waste heat recovery , 2007 .

[48]  K. Matsubara.  The Performance of a Segmented Thermoelectric Convertor Using Yb-Based Filled Skutterudites and Bi 2 Te 3 -Based Materials , 2001 .

[49]  Alberto A. Boretti.  Transient operation of internal combustion engines with rankine waste heat recovery systems , 2012 .

[50]  Ulrich Hopman,et al.  Diesel Engine Waste Heat Recovery Utilizing Electric Turbocompound Technology , 2005 .

[51]  Saiful Bari,et al.  Additional Power Generation from the Exhaust Gas of Diesel Engine by Bottoming Rankine Cycle , 2013 .