This dataset contains wind-tunnel measurements obtained for a laboratory demonstrator of a small ducted wind turbine equipped with passive flow control devices, investigated under steady and transient operating conditions. Experiments were performed for both free-rotor and ducted-rotor configurations using controlled and repeatable operating regimes. The dataset includes time-resolved measurements of mechanical torque and rotational speed acquired during static tests at fixed tip-speed ratios, as well as during dynamic tests based on controlled acceleration and deceleration ramps. In addition, time-averaged static pressure measurements inside the duct casing are provided for selected static operating conditions of the ducted rotor configuration. A total of 48 experiments are included, each stored in a separate self-describing HDF5 file with explicit physical units, descriptive attributes, and structured experimental metadata. The dataset is intended to support experimental analysis, numerical and reduced-order model validation, and comparative studies of free and ducted wind turbine configurations.