Interfacial surface energies - stainless steel and titanium nitride substrates and CaCO3 and CaCHPO4 depositions

In order to control fouling of heat transfer units, it is significant if deposition formation can be predicted beforehand. For this purpose, multiphase computational fluid dynamics simulations are very useful, because surface properties of heat transfer materials, properties of depositions and process parameters can be taken into account in the simulations. In order to increase the accuracy of the results, molecular modelling was used to calculate interfacial surface energies between substrates and depositions. The focus was on the stainless steel surfaces and titanium nitride coated surfaces which are exposed to calcium carbonate and calcium phosphate depositions in dairy industry. Determination of the interfacial energies are based on the calculated free surface energies of materials which are very laborious to determine experimentally. In the present research, free surface energies were calculated for Cr/CrFe oxides and TiN substrates and CaCO3 and CaHPO4 depositions including work of adhesion values. As a result, detailed fouling mechanisms with energetics and interfacial energies were obtained.