As part of the development process of a proposed offshore floating wind/wave platform, a scale-model testing programme has been carried out at a narrow tank facility on a single oscillating water column (OWC) device. Previous proof-ofconcept testing was performed on a scale model of the proposed platform comprising thirty-two OWCs with control components. That testing programme, implemented at the Hydraulic and Maritime Research Centre, demonstrated the feasibility of the concept. However, the large number of interacting components in this complex system results in difficulties when attempting to study and model numerically the hydrodynamic and thermodynamic processes at work within the OWCs during operation. In order to better study these processes, the subsequent phase of narrow tank testing was planned based on a single-chamber OWC model as described herein. This model was constructed with similar dimensions and cross-sectional profile to that of one OWC chamber in the larger model. Various control components can be added to and removed from the new model to investigate in a systematic fashion the effect of each component. Theory to numerically model the OWC in various configurations has been developed. A comparison between the tank test results and those obtained for a specific setup is presented.