Determination of free and forced convection heta transfer from fin arrays of different spacing /
Mohd Khalis Aizat Abd Aziz
- Kuantan, Pahang : UMP, 2012
- xv, 51 p. : ill. (some col.) ; 30 cm. + 1 CD-ROM
Project paper ( Bachelor of Mechanical Engineering) -- Universiti Malaysia Pahang - 2012
Bibilography : p. 44-46
This study is about analysis of free and forced convection condition for specimen with fin and without fin. Fin is an extended surface that dissipates heat from or to the environment. Three specimens tested where one for without fin and another two are without the fin. The specimens are vertical plate, finned plate and circular staggered fins. The experiment starts with the free convection approaches which selected the five different power supplies to the chamber. Followed by the forced convection where two power selected which lower and higher power. Forced convection is about the assist by air or fluid. So, air is chosen then regulates five different speed of fan. Collect the temperature data from reading at the inlet, outlet and the wall temperature. Stops until the reading become constant at all taken point. Analysis of free convection starts with finding the Rayleigh number and Nusselt number using the air properties of film temperature. Then the theoretical and experimental heat transfer coefficient and amount of heat transfer can be determined. Coefficient for with fin specimen is higher than without fin specimen and the amount of heat transfer for specimen with fin is higher compare with the specimen without fin. Number fins increase will result the higher amount heat transfer. For forced convection is a bit different than the free convection manner that air is used, so the boundary layer should be estimate first by using the Renoylds number equation to determine either laminar or turbulent flow. Go after is Nusselt number calculation affected the value of theoretical heat transfer coefficient. For the experimental value is determined by using the power supplied value. Because of air, heat transfer energy by the energy exists as well the amount of heat flux. Circular staggered fins (with fin specimen) scored the highest value of coefficient heat transfer. The circular staggered fins also obtained the higher heat transfer amount due to the large surface area and the greater temperature difference. The experimental value for coefficient obtained no longer the same with the theoretical value because slight error will occur during the testing. The heat transfer also will be enhance with the increasing the velocity and sustain the flow to turbulent or transition for the forced convection case study. The higher of power supplied affecting the higher value of the heat transfer. Circular staggered cylinder fins mostly achieved the higher result for coefficient and the amount heat transfer rather than the other two specimens.