Modeling of a horizontal circulation open loop in two-phase helium

► We measured the mass flow rates evolution for a two-phase circulation loop in helium. ► The circulation loop is simulated with a 1D predictive model. ► The two-phase helium flow is based on the homogeneous model. ► The thermodynamic behavior and mass flow rates are reproduced with good accuracy. In the process of the cryogenic cooling system design of the superconducting magnet of the R3B spectrometer, heat and mass transfer in a two-phase He I natural circulation loop with a horizontal heated section has been investigated experimentally. The experiments were conducted on a 2m high experimental loop with a copper tube of 10mm inner diameter uniformly heated over a length of 4m. All data were obtained near atmospheric pressure. Evolution of the mass flow rates as a function of heat flux in steady state condition are presented and compared to a numerical model that have been developed to assist the design of such a cooling scheme. The model is based on a one-dimensional equations system, which includes mass, momentum and energy balances. It is based on the homogeneous model with a specific friction coefficient for the horizontal heated section. The model reproduces with an acceptable accuracy the experimental results and now serves as a tool for the design.