Variable Compression Ratio Engines

The main focus of this work is to study variable compression ratio engines. The study begins with an analyze of the benefits of a variable compression ratio for Otto Cycle engines including mechanisms that already exist, the usual constructive solutions and the project criteria adopted in the area. The kinematic and dynamic model of SVC Saab mechanism, using Newton-Euler equations, is developed. Also, the cylinder pressure curve is important to be determined. The pressure curve and the cylinder volume function will be evaluated analytically considering the variation of the compression ratio. Furthermore, in order to know the influence of the design parameters in kinematic and dynamic, some sensitivity analysis of the engine mechanism will be performed. Finally, a computational implementation of the engine mechanisms analyzed will be done in Matlab language. This implementation includes the crank mechanisms and its kinematic and dynamic analyzes. Copyright © 2009 SAE International.Schwaderlapp, M., Habermann, K., Yapici, K.I., Variable Compression Ratio A Design Solution for Fuel Economy Concepts (2002) SAE Technical Papers, (2002-91-1103), , MarchRoberts, M., Benefits and Challenges of Variable Compression Ratio (VCR) (2003) SAE Technical Papers, (2003-01-0398), , MarchHountalas, D., Zannis, T., Mavropoulos, G., Potential Benefits in Heavy Duty Diesel Engine Performance and Emissions from the Use of Variable Compression Ratio (2006) SAE Technical Papers, (2006-01-0081), , AprilPischinger, S., Yapici, K.I., Schwaderlapp, M., Habermann, K., Variable Compression in SI Engines (2001) SAE Technical Paper, (2001-24-0050), , SeptemberMendler, C., Gravel, R., Variable Compression Ratio Engine (2002) SAE Technical Papers, (2002-01-1940), , JuneLarsen, G.J., Research Engine for Evaluating the Effects of Variable Compression Ratio (VCR) And/Or Variable Valve Timing (VVT) (1991) SAE Technical Paper, (910053), , FebruaryDrangel, H., Reinmann, R., Olofsson, E., The Variable Compression (SVC) and the Combustion Control (SCC) - Two Ways to Improve Fuel Economy and Still Comply with World-Wide Emission Requirements (2002) SAE Technical Papers, (2002-01-0996), , MarchMoteki, K., A Study of a Variable Compression Ratio System with a Multi-Link Mechanism (2003) SAE Technical Papers, (2003-01-0921), , MarchRabhi, V., Beroff, J., Dionnet, F., Study of a Gear-Based Variable Compression Ratio Engine (2004) SAE Technical Papers, (2004-01-2931), , OctoberRabhi, D., Rabhi, V., Ranson, P., Gear Design and Dimensioning Study for a Variable Compression Ratio Engine (2005) SAE Technical Apers, (2005-01-3131), , JulyKlein, M., Eriksson, L., Methods for Cylinder Pressure Based Compression Ratio Estimation (2006) SAE Technical Papers, (2006-01-0185), , AprilKuo, P.S., Cylinder pressure in a spark-ignition engine: A computational model (1996) Journal Undergrad. Science, 3, pp. 141-145Eriksson, L., Andersson, I., An analytic model for cylinder pressure in a four stroke SI engine SAE Technical Paper, 111(2002-01-0371), pp. 726-733(2009) VCR Strategy: Experiments, Results, Prospects, , http://www.mce-5.com/vcr_strategy/experimentsResults_prosp.htm, MCE-5 Development S.A. April(2008) Fuel Consumption Reduction Potential"l, , http://www.mce-5.com/vcr_strategy/index.htm, MCE-5 Development S.A. DecemberNilsson, Y., Cylinder volume function for SVC engines (2001) Technical Report, , Linköping University, Department of Electrical Engineering, SwedenHeywood, J.B., (1988) Internal Combustion Fundamentals, , New York: McGraw-Hill, In