การเพิ่มการถ่ายเทความร้อนสำหรับการกลั่นตัวของสารทำความเย็น R134aในท่อที่มีเทปบิดเกลียวและท่อที่มีร่องขนาดเล็ก

Abstract

This engineering project was educated for enhancement condensation heat transfer of refrigerant in tube with twisted-tape insert and microfin tube. The system of experimental apparatus was design and constructed by using R134a refrigerant as working fluid, while the water as coolant. The test section was concentric heat exchanger have tube diameter, shell diameter and length 7.75,25.27and 2000 mm. respectively. The results from experimental were found that the tube with twisted tape insert have more heat transfer coefficient then microfin tube and smooth tube. Because of the turbulent flow of refrigerant in twisted - tape insert increment the heat transfer coefficient by moving their molecules.