Effects of corrugated plate type turbulators in a heat exchanger on heat transfer and pressure loss

In this thesis, many properties such as; heat transfer, pressure loss, entropy rate, efficiency, exergy loss and variation of NTU, of a corrugated plate type turbulator located in a double pipe co-axial heat exchanger are investigated. The effects of the design parameters such as geometry of the turbulator (thickness of the plate; t/d, width of the plate; w/d and pitch of the plate; p/d) and fluid flow (Re number) on the two target results; Nusselt number (Nu) and friction factor (f) are investigated by using Taguchi Design of Experiment Method. After running all experiments the results are statistically evaluated by using Variance Analysis Method (ANOVA). In addition to this, Grey Relational analysis is performed to show the multi-performance characteristics. As a result, it was seen that the most dominant parameter on Nu number is Re number whilst the weakest parameter is plate thickness (t/d). Contrary the most dominant parameter on friction factor is found as plate thickness (t/d). It was also seen that the pitch of the plate has no effect on friction factor. When the results are evaluated from the view of 2.Law, it was seen that to increase the plate thickness and the plate width, results with the increment of entropy rate (Ns). The effect of thickness on efficiency () is negligible, but the efficiency increases substantially when the width increases. The exergy loss (E*) increases when the plate thickness increases, but it decreases when the width increases. The effect of pitch on efficiency and exergy loss is negligible. Keywords: Turbulator, Taguchi Analysis, 2.Law analysis, Heat transfer enhancement