The validation of each simulation code used in foundry domain requires individual approach due to its specificity. This validation can by
elaborated on the basis of experimental results or in particular cases by comparison the simulation results from different codes. The article
concerns the influence of grey cast iron density curve and different forms of solid fraction curve Fs=f(T) on the formation of shrinkage
discontinuities. Solid fraction curves applying Newtonian Thermal Analysis (NTA) were estimated. The experimental and numerical
simulation tests were performed on the castings, which were made with Derivative Thermal Analysis (DerTA) standard cups. The
numerical tests were realized using NovaFlow&Solid (NF&S), ProCast and Vulcan codes. In this work, the coupled influence of both
curves on the dynamics of the shrinkage-expansion phenomena and on shrinkage defects prognosis in grey cast iron castings has been
revealed. The final evaluation of the simulation systems usefulness should be based on validation experiment, preceded by comparing the
simulation results of available systems which are proposed in given technology.
The paper presents the results of experimental-simulation tests of expansion-shrinkage phenomena occurring in cast iron castings. The
tests were based on the standard test for inspecting the tendency of steel-carbon alloys to create compacted discontinuities of the pipe
shrinkage type. The cast alloy was a high-silicone ductile iron of GJS - 600 - 10 grade. The validation regarding correctness of prognoses
of the shrinkage defects was applied mostly to the simulation code (system) NovaFlow & Solid CV (NFS CV). The obtained results were
referred to the results obtained using the Procast system (macro- and micromodel). The analysis of sensitivity of the modules responsible
for predicting the shrinkage discontinuities on selected pre-processing parameters was performed, focusing mostly on critical fractions
concerning the feeding flows (mass and capillary) and variation of initial temperature of the alloy in the mould and heat transfer
coefficient (HTC) on the casting - chill interface.