CHARACTERIZATION OF DRYOUT IN HELICAL-COILS

The prediction of the occurrence of dryout in helical coils is important for the proper design of the steam generators of some LMFBRs. Past work in this area is not satisfactory either in the prediction of the first dryout quality or in the treatment of the partial dryout region. Qualitative arguments are presented to show that dryout data can be classified into stratification-, redeposition- and entrainment-dominated dryout. Results obtained by various laboratories including experiments carried out at CENG, Grenoble, are used to develop transition criteria for these zones in a 'dryout map'. Correlations are given for dryout quality in each group. An analysis of the partial dryout region is also presented. © 1990.