Boiling in helical coils is involved in many applications including nuclear and conventional boilers, air conditioning and refrigeration, and chemical processing. It is therefore important to be able to predict CHF accurately. Many experimental studies have been done and many correlations have been proposed. However, there has been no comprehensive comparison of correlations with data to determine their accuracy. The present study was done to fulfil this need. A database of published test data from 16 sources was prepared and compared to a number of correlations for straight tubes as well as those for coils. The data included six fluids (water, nitrogen, refrigerants), mass flux 89 to 5474 kg m(-2) s(-1), and critical qualities from -0.5 to 1.16. Tube diameters range from 4.5 to 20 mm and ratio of coil diameter to tube diameter (D-c/D-t) from 6.5 to 108. None of the correlations for coils was found satisfactory. Four of the five straight tube correlations gave fairly good agreement. Ranges of parameters have been identified in which the straight tube correlations can be used for design.
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