An integral method of calculation of stabilized heat transfer in tubes in single-phase near-critical region

Abstract

The modified method of calculation of “stabilized” heat transfer in tubes, which was developed previously and tested with gases of varying properties, is adapted to the conditions of single-phase near-critical region. Calculations are performed for water at a pressure from 22.5 to 29.4 MPa in the enthalpy range from 500 to 3500 kJ/kg under conditions of turbulent flow in heated tubes 4 to 16 mm in diameter and with heat loads from 0.2 to 1.2 kJ/kg. The calculation data are compared with known empirical formulas of different authors and used for refining the practical methods of calculation of heat transfer and drag under conditions of normal heat transfer. The question is discussed of the consequences of changing to a new standard of properties of water in the supercritical region of parameters from the standpoint of accuracy of thermohydraulic calculations.