The flow of steam, at the Wilson point, begins to condensate through nucleation, and its non-equilibrium conditions are suppressed by forming the critical droplets that decreases the Gibbs energy, and then the condensation shock occurs. Droplet radius -r- and Wetness fraction -WF- or heat release rate due to phase change - - are important parameters in the design and operation of high-pressure -HP- wet steam equipment. The experimental, analytical, and numerical methods have been considered as cost-intensive, complicated, and time-consuming, respectively. Therefore, in this study, using only dry vapor data, an innovative method based on Buckingham Pi theorem is proposed to estimate the droplet radius and WF or . Also, an acceptable threshold for identification of Wilson point location is suggested. First, the results of analytical modeling have a good agreement with the experimental data at the range 25-35 bars. Next, using dimensional analysis, Droplet-Wetness Parameter -DWP- is obtained as a dimensionless number which is a function of effective parameters. By curve fittings, two regression equations are proposed for calculating r and WF at the end of nozzles. Finally, the results of the proposed equations are compared with those of available analytical models. There is a good agreement between the current method and available models in literatures. This innovative method, based on dimensional analysis, is introduced for preliminary design of HP nucleating steam equipment.

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