Experimental and numerical study of the thermal hydraulics characteristics of a helical-coiled once-through steam generator

• A experiment study of a helical-coiled once through steam generator is conducted. • The test section is composed by 85 helical tubes which is divided into 10 layers. • The effect of operational parameters on the heat transfer characteristic is analyzed. • An 1D code is developed and verified by the experimental results of this study. The helical-coiled once-through steam generators are widely used in advanced reactors. The present study carries out an experimental study on a type of helical-coiled once-through steam generator under different thermal power conditions. The configuration consists of 85 helically coiled tubes divided into ten layers with various coil diameters. The experiments are performed under various thermal power conditions to collect key thermal-hydraulic parameters of the helical-coiled once-through steam generator. The experimental result shows the outlet temperature of the tube-side reaches the maximum value at 4.2 MW, and the average heat transfer coefficient increases with decreasing tube-side pressure and increasing shell-side inlet temperature. Then a thermal-hydraulic code for helical-coiled once-through steam generators is developed and verified by the experimental results in this paper. A comparison of the simulation results with the experimental results illustrates that the code can accurately predict the heat transfer rate of the helical-coiled once-through steam generator. The prediction errors of shell-side and tube-side outlet temperature are within ±1 °C.