Perpustakaan Digital ITB
2007 TA PP SITI SARAH FARMAWATI 1-COVER.pdf
2007 TA PP SITI SARAH FARMAWATI 1-BAB1.pdf
2007 TA PP SITI SARAH FARMAWATI 1-BAB2.pdf
2007 TA PP SITI SARAH FARMAWATI 1-BAB3.pdf
2007 TA PP SITI SARAH FARMAWATI 1-BAB4.pdf
2007 TA PP SITI SARAH FARMAWATI 1-BAB5.pdf
2007 TA PP SITI SARAH FARMAWATI 1-PUSTAKA.pdf
Finned-tubes heat exchanger consists of bank of bare tubes with fins attached outside of it as extended surfaces. The addition of fins is done to enhance heat transfer coefficient.
Heat exchanger performance is derived from heat transfer. It is observed in two ways; inner and outer fluid-side, with tube as the reference. This study uses air as the outer fluid with cross flow arrangement. Convective heat transfer is a major significance in the calculation of finned-tubes heat exchanger performance. It is influenced by tube and fin conductivity and fin efficiency. Thermal performance is analyzed with Number of Transfer Units (NTU) method and logarithmic mean temperature difference (ΔTlm) method if inlet and outlet temperatures of both fluids are known. This study only considers the pressure drop outside the tubes which occurs when the air passes through the fins and the tube arrays.
This study derives eight Microsoft Excel-based programs for calculation of heat exchanger performance; air heater, air cooler, air-cooled condenser, and evaporator and the reversed calculation steps. The calculation results are compared with example case in Process Heat Transfer book by Hewitt and Guentner Product Calculator 2003.
The calculation results between the programs and Guentner Product Calculator 2003 are different. The calculations in Guentner Product Calculator 2003 are based on heat exchanger specifications that are produced.