Pseudo-film boiling

Also, two special phenomena (for their definitions, see the beginning of this appendix) may appear along a heated surface (1) pseudo-boiling and (2) pseudo-film boiling. 

A4.2.2 Pseudo-boiling and pseudo-film boiling phenomena... 

The process of pseudo-film boiling (ie, low-density fluid prevents high-density fluid from rewetting a heated surface) is similar to film boiling, which occurs at subcritical pressures. Pseudo-film boiling leads to DHT. However, the pseudo-film boiling phenomenon may not be the only reason for DHT. Ackerman (1970) noted that unpredictable heat transfer performance was sometimes observed when the pseudocritical temperature of the fluid was between the bulk fluid temperatiire and the heated surface temperature. 

Lee and Haller (1974) found heat flux and tube diameter to be the important parameters affecting the minimum mass flux limits to prevent pseudo-film boiling. Multilead ribbed tubes were found to be effective in preventing pseudo-film boiling. 

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