Experimental and numerical investigation of local bubble parameters for subcooled flow boiling in a pressurized annulus

•Experimental and numerical investigations were performed for subcooled nucleate flow boiling.•Unique data set for bubble parameters is presented covering radial profiles at multiple elevations.•Experimental data was numerically simulated by the CUPID code developed at KAERI.•Heat flux partitioning model was improved for better performance under high-pressure conditions.