oa Proof-of-Concept Study on Heat Transfer in a CO2 Pipeline System

Heat flux sensors have been tested in single-phase and two-phase flow of pure industrial-grade CO2 in the FALCON CO2 flow loop at IFE, with an inner pipe diameter of 44.3 mm and a wall thickness of 3.25 mm. The sensors have been tested on a plain uninsulated steel pipe, on a steel pipe insulated with 13.5 mm foam and with an annular temperature control jacket circulating a water/glycol mixture. The sensor performance was found to be satisfactory for all the three setups studied. Comparisons against commonly used engineering heat transfer correlations show reasonable agreement in most cases, although some tuning of the outer heat transfer coefficient is required to get a good match both in the case where the external medium was ambient air and when the external medium was a water/glycol mixture. Transients are nevertheless well captured by the sensors.