This paper presents temperature estimations via two simple CFD simulations of a dynamic phenomenon in a transparent tank (cylindrical heater rod submerged into water in a glass tank) with ANSYS Fluent and comparison with the optical measurement results obtained via the Digital Holographic Interferometry (DHI) method and thermocouples. Our CFD simulations predict temperature values in good agreement (within 5% error limit) compared to thermocouples and DHI. Furthermore, the great advantages of DHI technique for such kind of reliable, fast, in time, accurate and contactless measurements were highlighted. Data validations of our simulations could lead to further investigations through the CFD simulating technique for a wide range of applications.