Validations—Modeling and Optimization

The developed mathematical models and the optimized parameters are validated through confirmatory experimental tests as well as using statistical tools. The models are validated through a comparative study of actual experimental results and predicted results from the models corresponding to the geometrical characteristics (top width; XT, bottom width; XB, depth; Z, and taperness of sidewalls) associated with each of the five sizes of micro-channels (100x50 µm, 200x100 µm, 400x20 µm, 800x400 µm, and 1000x500 µm) generated in three aerospace materials (nickel alloy; NA, titanium alloy; TA, and aluminum alloy; AA). Then the mean differences between the actual results and the model predicted results were compared through paired-t-test. The paired t-test performed for every response of every micro-channel was evaluated by setting the analysis assumptions such as confidence level of 95 %, t-values and p-values of the mean differences of actual and predicted results.