Numerical study of performance of flat and perforated radiant heat shields for offshore structures

Abstract

Heat shields are an essential safety facility on offshore structures to protect the workers and the equipment on deck from the violent radiant heat flux and the high temperatures of the flare tower. In this study, a series of Computational Fluid Dynamics (CFD) simulations were performed to investigate the thermal characteristics of radiant heat shields on offshore structures in order to obtain a precise prediction of those reduction performances on heat flux and temperature. CFD methodologies for the radiant heat transfer simulation were suggested for grid, iteration, and time step with physical modelling methods of heat transfer considering the convection effect and the heat flux sensor, including the scaling method for the simulation of a perforated heat shield. The reduction ratios of the heat flux and temperature were obtained for the case without the heat shield and for a flat and perforated heat shield under the heat source of 25 kW/m2 for various distances from the heat shield, and the results were compared with the experimental results. Analytical estimation methods were included in the study of the radiant heat flux and temperature, and an empirical formula was provided for the performance of the heat shields based on the CFD results.

Keywords

• Heat shield
• Flare tower
• Computational fluid dynamics
• Radiation
• Heat flux