Maintaining high aircraft’s propulsion system reliability requires a good knowledge of engine’s heat transfer
conditions at each engine running time. Even though the flow around the cylinder may be steady, the heat flux from
the engine is not evenly distributed. This is caused by varied engine head and fins geometry and uneven heat transfer
coefficient distribution. The lack of knowledge of the local heat transfer coefficient values and time coefficients for
the transient heat transfer make it unfeasible to make an analytical model for a given geometry. One transient
Computational Fluid Dynamics simulation does not solve the heat transfer fully. Only a conjugate simulation allows
an in-depth analysis of a transient heat transfer. The Combustion and species transport fluid simulation is coupled
to the temperature field solid simulation. This work presents the methods and results of such conjugate heat transfer
simulation. The change of heat flux parameters in respect to time is shown. The results are verified by the real engine
measurements