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Experimental Advanced Superconducting Tokamak (EAST) is the first fully superconducting tokamak in the world, which is operating at ASIPP Hefei, China, since 2006.In previous EAST campaigns the supercritical helium coolant temperature increase at the outlet of the Central Solenoid (CS) could not be reconciled with the estimation of AC (coupling) losses,which is calculated using the nτ value measured from short samples in the magnet design phase.In the last EAST experimental campaign, conducted in 2014, dedicated tests were performed to address this issue.The AC losses of CS coil with trapezoidal and sinusoidal current scenarios were tested, and the steady state hydraulic characteristic of the conductors was measured.Since only few diagnostics are available in the experiment, i.e.inlet flow meter, inlet and outlet temperature sensors and pressure taps, the evaluation of the internal state of the magnet during operation requires detailed analysis.In this paper, the state-of-the-art thermal-hydraulic code 4C is applied to study the experimental results of the last EAST campaign.It is found that the simulated outlet temperature rise can be best fitted to the experimental results by adjusting the coupling time constant.In order to simplify the problem, the model is developed adopting the minimum level of complexity of the cryogenic circuit, which is needed for the analysis.The entire CS coil (CSl-6 modules) is considered, and the actual current scenarios in the experiment are used to obtain the AC losses.First, the value of nτ which best fits a subset of the experimental results for single CS modules is found (model calibration).Then the resulting m value is applied to simulate another,reasonably independent subset of the experimental results, also when the entire coil is charged(model validation).