Scaling of thermohydraulic systems

The importance of scaling is demonstrated for experiments in small-size test facilities which are used to simulate the thermohydraulic system response of full-size industrial plants. It is shown how scaling facilitates (1) the quantitative ranking of thermohydraulic processes in their order of priority, (2) the rational selection of a test matrix, and therewith (3) the efficient allocation of resources for resolving technical issues of reactor safety. Thermohydraulic processes in components and the system of components are modeled. 29 Scaling groups are presented for systems with forced flow and natural circulation of single- and two-phase flows. System compliances and the matrices of flow inertia and impedance are introduced and scaled, to obtain the scaling criteria for the global interaction between components of integral systems.