Unsteady state heat flow in the exhaust valve in turbocharged Diesel engine covered by the layer of the carbon deposit

Purpose: The determination of the temperature distribution, temperature gradients and thermal stresses in the exhaust valve with using the layer of the carbon deposit in initial phase of the work of turbocharged Diesel engine.Design/methodology/approach: The results of calculations of the temperature distribution, temperature gradients and thermal stresses in the exhaust valve of turbocharged Diesel engine with using the layer of the carbon deposit on the different surfaces of the valve were received by means of the two – zone combustion model and the finite element method.Findings: The computations presented the possibility of use of the geometrical models of the layer of carbon deposit on the different surfaces of the exhaust valve and heat transfer on individual surfaces of the exhaust valve used by the variable values of the boundary conditions and temperature of working medium in initial time of the working engine.Research limitations/implications: The modelling of thermal loads were carried out by analysing the temperature distribution, temperature gradients and thermal stresses in the exhaust valve in initial phase of the work of turbocharged Diesel engine.Originality/value: The layer of the carbon deposit was used for modelling of thermal loads in the exhaust valve as the geometric model with the use of material properties. The results obtained allow to analyse distribution of temperature, temperature gradients and thermal stresses in the exhaust valve.