Steady-State and Transient Prediction of a 19-Tube Once-Through Steam Generator Using RELAP5/MOD1 Academic Article uri icon


  • Comparisons of the predictions of RELAP5/MOD1 to data obtained from a 19-tube model of a once-through steam generator (OTSG) were performed. The initial results were not satisfactory since the predicted outlet steam temperature was much too low. This discrepancy was traced to the inappropriate use of the modified Zuber critical heat flux (CHF) correlation for the conditions occurring during integral economizer OTSG operation. A study of available low-flow CHF correlations was performed that showed that either the Macbeth or Biasi correlations used in conjunction with RELAP5/MOD1 would produce good agreement with both the steady-state and transient data for the integral economizer-type OTSG. The Macbeth correlation was the best for the OTSG with a recirculation path; however, it was not entirely satisfactory due to a slight delay in its prediction of CHF. A loss-of-feedwater transient was modeled using the Macbeth CHF correlation and compared to experimental data with satisfactory results.

author list (cited authors)

  • Hassan, Y. A., & Morgan, C. D.

citation count

  • 5

publication date

  • January 1983