TY  - MANSCPT
AU  - Sashwin Nair A/l Gobinathan,
TI  - Experimental and numerical investigation of tube angle, fin shape and winglet effects on compact heat exchanger with parametric optimization
SN  - THE0010208 (Local)
PY  - 2025///
CY  - Kuantan, Pahang
PB  - UMPSA
KW  - Faculty of Mechanical and Automotive Engineering Technology
KW  - Dissertations
KW  - Universities and colleges
KW  - Theses
N1  - Faculty of Mechanical and Automotive Engineering Technology; Thesis (Master of Science) -- Universiti Malaysia Pahang – 2025; Includes bibliographical references
N2  - Compact heat exchangers (CHE) are among the most often used heat exchanger (HE) in the industry due to its better advantage over other types of heat exchangers. Numerous geometric (fin spacing, tube inclination angle, etc.) and process (airflow velocity, liquid temperature, etc.) characteristics affect the way these small HEs work. Most of the research focused more on the plain fin with the addition of winglets whereas for wavy fin and rectangular fin are not fully examined. Furthermore, effect of tube inclination angle on plain, wavy and rectangular fins with addition of winglets are not examined yet. Even though the experimental and numerical show a very small difference in their results, there are limitations in the experimental study. The flow through the CHE is not observable with our naked eyes. The research work on the geometric parameters have been done separately. A combination of both types of research works are something new and needs to be done in comparison with flat fin for heat transfer enhancement. The main objective of this study is to investigate the heat transfer performance of flat tube CHE at various tube inclination angles and fin shapes with the addition of winglet. The second objective is to determine the optimum geometric and process parameters for enhanced heat transfer. Aluminium fins were fabricated for the study based on the fin type parameter which are plain, wavy and rectangular. Wavy angle and height were fixed at 162.1° and 1.5mm respectively for enhanced heat transfer. To achieve the objective of this research, 6 different tube inclination angles (0°, 30°, 60°, 90°, 120° and 150°) were investigated using plain, wavy and rectangular fin type. The experiment was conducted in an open wind tunnel and the working fluid used was air to investigate the thermal performance of the fin-and-tube HE. The wind tunnel consists of an inlet section, flow straightener, test section, and devices to measure airflow velocity, the temperature of air and pressure difference, temperature controller, suction fan and frequency inverter. By applying Ansys FLUENT software, a three-dimensional (3D) numerical technique was used to calculate the laminar flow condition for both inline and staggered tube arrangements. In addition, a simulation of a flow visualisation based on winglet computational domain with and without was conducted. Based on the results, the tube configurations with the highest average heat transfer coefficient (120°) and the lowest average pressure drop penalty (30°) were found to be in the same location. In addition, it has been shown that staggered tube arrangements transfer heat more efficiently than inline arrangements. In addition, because of their larger heat transfer surface area, fins with winglets conduct heat more efficiently than fins without them. As a result, an inclination angle of 120° is advised when huge heat transfer is required, and 30° or 150° is advised if pumping power is the main issue. In order to improve the heat transfer, addition of winglet with 120° tube inclination and rectangular fin would be an ideal choice. The optimisation result shows that the heat transfer coefficient increases with the increase in air velocity, fin spacing, and tube inclination angle. In addition, when the air velocity and tube inclination angle decrease, the pressure loss is at its lowest. Apart from that, the high friction drag generated by the tube surfaces contributes to an increase in this pressure drop. Furthermore, it is evident that the fin spacing has little to no impact on the pressure drop
ER  -