Experimental Heat Transfer Analysis from Helical Coiled Tubes with the Same Surface Area

Abstract

Helical coiled tubes are commonly used inserted in water storage tank. In this study, an experimental investigation was carried out to obtain heat transfer characteristics of different geometric dimensions in helical tubes under steady state conditions. Helical coiled tubes of different geometric dimensions with the same overall length and total surface area were fabricated from the same copper tubes. The helical coiled tubes were placed in a hot water tank which could be adjusted to different water temperatures. Cold water was pumped into the helical coiled tubes at different flow rates with 20 °C. The experiments were carried out for laminar flow in the range of Re numbers between 3394 and 8332. Helical coiled tube Nu number was determined and compared with the literature. Then, the effectiveness’s of helical coiled tubes were calculated using the ε-NTU method.