thermalhydraulic

Thermal hydraulic, sometimes written as thermal-hydraulic, refers to the study of heat transfer and fluid flow in engineering systems. It combines principles from thermal engineering and hydraulics to analyze how energy is transported by fluids, how heat is removed or added, and how phase change affects those processes. The field encompasses single-phase and multiphase flow, as well as phenomena such as boiling, condensation, and two-phase flow regimes, which influence temperature distribution, pressure drop, and system efficiency.

Central concepts include the conservation of mass, momentum, and energy, along with the properties of the working fluids. Models range from simple correlations to detailed computational methods. Two-phase flow modeling often uses approaches such as homogeneous equilibrium, drift-flux, or two-fluid formulations. In many applications, predicting onset of boiling, critical heat flux, flow instability, and thermal fatigue are essential for safe and reliable design.

Methods used to study thermal hydraulics include experimental measurements in test facilities, analytical and semi-empirical correlations, and numerical simulations. Computational fluid dynamics (CFD) and system thermal-hydraulics codes simulate local phenomena and whole-system behavior, respectively, and are frequently coupled with other physics such as neutronics in nuclear reactor analysis.

Applications span power generation, chemical processing, HVAC, and electronics cooling. In nuclear engineering, thermal hydraulics is crucial for reactor safety analyses, including emergency cooling scenarios and loss-of-coolant events.