Due to marked differences of material properties and combustion characteristics between hydrogen and carbon-based fuels, an increased heat flux inside the cylinder of hydrogen-fuelled internal combustion enginesoccurs.The present study aims for a simulation mode l that describes the wall heattrans fer with in theentirerange of enginecalibrationpossibilities.Conductedexperimentsonahydrogenengineequipped with temperature sensors provide the base for the present study. Using the surface temperature method, highly resolved instantaneous surface heat fluxes can be identified. These measurements are compared with results from published heat transfer models that are originally developed for conventional fuels. Asnosatisfyingresultwiththesemodelscanbeobtainedforthehydrogenengine,amodifiedheattransfermodelisderivedandvalidatedbasedontheexperimentaldata.Necessarydevelopmentsoncharacteristic model features lead to a distinctive model for a hydrogen engine. It is demonstrated that the proposed model attains a consistently high prediction quality for a broad range of engine calibration variabilities.