Final Program EXPRES 2012 - Conferences

Temperature of the components [C]900800700600500400300200100Full loadUsual loadTminTmaxthe reliability of the modules have not been tested whichis also an important factor of the practical applications.The data presented in the tables clearly indicates thateven with today’s thermopile technology we have meansto cover part of the electrical consumption inautomobiles. On the other hand, at presentit is only justified to use the thermopile technology in thevehicles with greater fuel consumption. With furtherdevelopment of the new types of the TEG converters itwill became more and more economical toinstall the thermopile technology in the vehicles withsmall diesel consumption.00 0,6 1,4 2,3 3,35 rear side250TEC1-12707 TEC1-12708 Melcor HT9-3-25 Bi2Te3 N31 Melcor HT6-12-40 Bi2Te3 N31Figure 2. An approximate temperature distribution of agasoline fueled automobile (BMW 318i) with twodifferent operating modesThe temperature distribution of a diesel engineautomobile is different compared to a gasoline fueledautomobile because of the additional equipments (DieselParticulate Filter DPF, Diesel Oxidizing Catalyst DOC).On smaller vehicles the DPF should be active(additionally fueled) equipment which further increasesthe temperature of the exhaust system around and afterthe DPF. Generally the highest temperatures occurredafter the DPF [6]. This information is important todesigners to specify the best location of the TEG modulesto convert as much wasted heat as possible to electricity.Table III shows the typical surface temperature [ o C] ofthe components of an exhaust system of smaller sizeddiesel engine trucks and the assumed average contactsurface area [m 2 ] to transfer heat from the differentcomponents of the exhaust system toward the TEGmodules.TABLE III.TEMPERATURE DISTRIBUTION OF THE EXHAUST SYSTEM [6]Location Ford Dodge Sterling GMC AreaDiesel Particulate 295 168 196 307 0.3Filter DPFAfter DPF 375 300 293 446 0.1Before DOC 231 193 241 435 0.1Diesel OxidizingCatalyst DOC356 218 228 308 0.2It can be clearly seen from Figure 3 that the generatedelectrical power is strongly depend on the location of thethermocouples because the temperature of the exhaustsystem is varying along the different components.In the same operating environment the TEG modulesgive a slightly better performance in case of electricalpower production than the other modules. But thereliability of the modules have not been tested which isalso an important factor of the practical applications.III. CONCLUSIONIn the same operating environment the Melcormodules give a slightly better performance in case ofelectrical power production than the other modules. ButGenerated electrical power [W]200150100500Diesel Particulate FilterDPFAfter DPF Before DOC Diesel Oxidizing CatalystDOCLocation of the exhaust systemFigure 3. The influence of the position TEG generatoron the amount of the generated electrical powerREFERENCES[1] 1. K. T. Zorbas, E. Hatzikraniotis, K. M. Paraskevopoulos, Powerand efficiency calculation in commercial TEG and application inwasted heat recovery in automobile.[2] 2. J.P. Carmo, J. Antunes, M.F. Silva, J.F. Riberio, L.M.Goncalves, J.H. Correia, Characterization of thermoelectricgenerators by measuring the load-dependence behavior,Measurement 44, (2011), 2194-2199.[3] 3. R.Y. Nuwayhid, D.M. Rowe, G. Min, Low cost stove-topthermoelectric generator for regions with unreliable electricitysupply, Renewable Energy 28, (2003), 205-222.[4] 4. Fankai Meng, Lingen Chen, Fengrui Sun, Numerical model andcomparative investigation of a thermoelectric generator withmulti-irreversibilities, Energy, 36, (2011) 3513-3522.[5] 5. Wei-Hsin Chen, Chen-Yeh Liao, Chen-I Hung, A numericalstudy on the performance of miniature thermoelectric cooleraffected by Thomson effect, Applied Energy, 89, (2012) 464-473.[6] 6. Ralph H. Gonzales, Diesel exhaust emission system temperaturetest, San Dimas Technology & Development Center, San Dimas,California, December 2008.[7] N.ESPINOSA, M.LAZARD, L.AIXALA, H.SCHERRER:"Modeling a Thermoelectric Generator Applied to DieselAutomotive Heat Recovery" Journal of ELECTRONICMATERIALS, Vol. 39, No. 9, 2010 pp: 1446-1455[8] MOLAN LI, SHAOHUI XU, QIANG CHEN, LI-RONG ZHENG:"Thermoelectric-Generator-Based DC–DC Conversion Networksfor Automotive Applications" Journal of ELECTRONICMATERIALS, Vol. 40, No. 5, 2011, pp: 1136-1143[9] HIROSHI NAGAYOSHI, TATSUYA NAKABAYASHI,HIROSHI MAIWA, TAKENOBU KAJIKAWA: "Developmentof 100-W High-Efficiency MPPT Power Conditioner andEvaluation of TEG System with Battery Load" Journal ofELECTRONIC MATERIALS, Vol. 40, No. 5, 2011 pp: 657-661[10] S. B. Schaevitz, A MEMS Thermoelectric generators, MasterThesis, MIT, September 2000.31