Equations describing the transport of water and a binary salt through semipermeable membranes are presented. Methods of experimentally determining the resulting six independent transport parameters have been tested. Measurements of these parameters on Loeb-type membranes are presented for curing temperatures of 75°, 84°, and 95°C. If the membrane concentration is characterized by the geometric mean activities of adjacent solutions, the osmosis parameters as defined are concentration-independent up to 0.1 M. They are also independent of the pressure difference across the membrane up to 600 p.s.i.g. Above 600 p.s.i.g. compaction causes a decrease in the transport parameters. Coupling between the different driving forces is quantitatively measured. During reverse osmosis the water flux is not influenced by coupling and can be described by one parameter. The salt flux shows coupling to the water flow and requires two parameters to describe its variations. The reciprocal relations are valid to within at least an order of magnitude. Since water flux coupling is small, the uncertainty in the magnitude of the corresponding coupling parameter is large. Electrical conductivity in a membrane is one third or one fourth of that in the adjacent solution. The transference number of the sodium ion decreases from 0.85 at 0.0035M to about 0.3 at 0.075M.[Equations describing diffusive flow of water and a binary " salt through a semipermeable membrane are presented. The six independent transport parameters defined by these equations have been measured for sodium chloride and water flow through Loeb-type cellulose acetate membranes (Loeb and

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Korea Atomic Energy Research Institute (KAERI) started the experimental research on moderator circulation as one of a the national research and development programs from 2012. This research program includes the construction of the moderator circulation test (MCT) facility, production of the validation data for self-reliant computational fluid dynamics (CFD) tools, and development of optical measurement system using the particle image velocimetry (PIV). In the present paper we introduce the scaling analysis performed to extend the scaling criteria suitable for reproducing thermal-hydraulic phenomena in a scaled-down CANDU- (CANada Deuterium Uranium-) 6 moderator tank, a manufacturing status of the 1/4 scale moderator tank. Also, preliminary CFD analysis results for the full-size and scaled-down moderator tanks are carried out to check whether the moderator flow and temperature patterns of both the full-size reactor and scaled-down facility are identical.

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