Numerical investigation on thermal hydraulic characteristics of steam jet condensation in subcooled water flow in pipes

•Steam jet condensation in subcooled water flow in pipes is studied numerically.•A two-resistance model is applied for calculating interfacial heat and mass transfer.•The total pressure peaks at the two-phase region's end due to water dynamic pressure.•The expansion-contraction passage makes a steam jet accelerates to supersonic state.•Heat transfer coefficients based on area and volume decrease as steam pressure rises.