Technical Paper
Experimental and Theoretical Investigation of Turbulent Burning Model for Internal Combustion Engines
1974-02-01
740191
A model for describing turbulent flame propagation in internal combustion engines is presented. The model is based upon the assumption that eddies having a characteristic radius ℓe are entrained by the flame front at a turbulent entrainment velocity ue and subsequently burn in a characteristic time τ = ℓe/uℓ, where uℓ is the laminar flame speed for the fuel-air mixture. An approximate analytic method for determining the equilibrium state of the burned gases is also presented. To verify the predictions of the model, experiments were carried out in a single-cylinder research engine at speeds from 1000-3200 rpm, spark advances from 30-110 deg btc and fuel-air equivalence ratios from 0.7-1.5. Simultaneous measurements of the cylinder pressure and the position of the flame front as a function of crank angle were made, and good agreement with the predictions of the model was obtained for all operating conditions.
