The Nuclear Industry Requires Accurate Modeling Efforts to Ensure Safety Standards Are Consistently Achieved. to that End, the Sensitivity of Void Fraction and Interfacial Area Concentration Predictions to Changes in the Interfacial Area Concentration Modeling Methods Was Evaluated. Several Interfacial Area Concentration Correlations and Interfacial Area Transport Equation Coalescence and Breakup Models Have Been Compared to the Data of Schlegel Et Al. and Shen Et Al. using a Computational Tool Developed in MATLAB. Bubble Coalescence and Breakup Empirical Constants Were Optimized for the Group Void Fractions and Interfacial Area Concentrations using the Computational Tool and the Surface Response Method. the Results Indicate that the Transport Equation Approach Has a Higher Accuracy for Both the Void Fraction and Interfacial Area Concentration Predictions Than the Correlation Approach. the Smith Et Al. Model is Shown to Have the Highest Void Fraction Predictive Accuracy. the Optimized Model is Shown to Successfully Increase Accuracy of the Interfacial Area Concentration Prediction. This is Also the Highest Accuracy Observed for Interfacial Area Concentration Predictions.