Overview of Void Fraction Measurement Techniques, Databases and Correlations for Two-Phase Flow in Small Diameter Channels
Álvaro Roberto Gardenghi,
Erivelto dos Santos Filho,
Daniel Gregório Chagas,
Guilherme Scagnolatto,
Rodrigo Monteiro Oliveira,
Cristiano Bigonha Tibiriçá
Affiliations
Álvaro Roberto Gardenghi
Heat Transfer Research Group, Department of Mechanical Engineering, Sao Carlos School of Engineering, University of São Paulo, Av. Trab. São Carlense, 400, São Carlos SP 13566-590, Brazil
Erivelto dos Santos Filho
Heat Transfer Research Group, Department of Mechanical Engineering, Sao Carlos School of Engineering, University of São Paulo, Av. Trab. São Carlense, 400, São Carlos SP 13566-590, Brazil
Daniel Gregório Chagas
Heat Transfer Research Group, Department of Mechanical Engineering, Sao Carlos School of Engineering, University of São Paulo, Av. Trab. São Carlense, 400, São Carlos SP 13566-590, Brazil
Guilherme Scagnolatto
Heat Transfer Research Group, Department of Mechanical Engineering, Sao Carlos School of Engineering, University of São Paulo, Av. Trab. São Carlense, 400, São Carlos SP 13566-590, Brazil
Rodrigo Monteiro Oliveira
Heat Transfer Research Group, Department of Mechanical Engineering, Sao Carlos School of Engineering, University of São Paulo, Av. Trab. São Carlense, 400, São Carlos SP 13566-590, Brazil
Cristiano Bigonha Tibiriçá
Heat Transfer Research Group, Department of Mechanical Engineering, Sao Carlos School of Engineering, University of São Paulo, Av. Trab. São Carlense, 400, São Carlos SP 13566-590, Brazil
Void fraction is one of the most important parameters for the modeling and characterization of two-phase flows. This manuscript presents an overview of void fraction measurement techniques, experimental databases and correlations, in the context of microchannel two-phase flow applications. Void fraction measurement techniques were reviewed and the most suitable techniques for microscale measurements were identified along its main characteristics. An updated void fraction experimental database for small channel diameter was obtained including micro and macrochannel two-phase flow data points. These data have channel diameter ranging from 0.5 to 13.84 mm, horizontal and vertical directions, and fluids such as air-water, R410a, R404a, R134a, R290, R12 and R22 for both diabatic and adiabatic conditions. New published void fraction correlations as well high cited ones were evaluated and compared to this small-diameter void fraction database in order to quantify the prediction error of them. Moreover, a new drift flux correlation for microchannels was also developed, showing that further improvement of available correlations is still possible. The new correlation was able to predict the microchannel database with mean absolute relative error of 9.8%, for 6% of relative improvement compared to the second-best ranked correlation for small diameter channels.
