ANALISIS PERPINDAHAN PANAS DAN EFISIENSI EFEKTIF HEAT EXCHANGER SHELL AND TUBE (Analysis of Heat Transfer and Effective Efficiency Shell and Tube Heat Exchanger)

Abstract

Heat Exchanger is the equipment used to perform the process of heat exchange between two fluids, both liquid (hot or cold) and gas, where this fluid has different temperatures. Some types of heat exchanger are frequently used shell and tube heat exchanger, double pipe heat exchanger and plate heat exchanger. This research aims to determine the rate of heat transfer with temperature variation on the inlet tube and knowing the effective efficiency on heat exchanger shell and tube type. A heat exchanger used in this study is made of carbon steel with specifications include it est specifications of the shell consists of an inner diameter (IDs) 10 in, the number of baffle (N) 7 pieces, the number of passes (ns) 1 pass, and fluid used in the form of hot water; while the specification of the tubes that is outer diameter (ODT) ¾ in, the number of tubes (Nt) 12 pieces, a long tube (L) of 100 cm, number of passes (nt) 2 pass, tube pattern it est triangular pitch, and the fluid being used it est cold water. From these data, it is the heat exchanger is a heat exchanger used for fluid warming or fluid cooling process. The heat exchanger then conducted the testing. Cold water flows into the tube at a steady pace and hot water was flowed into the shell at a steady pace that is by opening valve of ½ rounds, this was done within a period of 8 minutes four times testing where Thin is maintained constant at at temperature of 40°C and Tcin on testing 1, 2, 3, and 4, in a row (15, 20, 25, 30)°C. By measuring the temperature changes that occurs between the entry and exit of shell and tube, are used to determine the heat transfer rate (qact and qmax) and effective efficiency (ηeff) of the shell and tube heat exchanger. The experimental results obtained were then compared with the result of theoretic. The results showed that the effect of the values of ΔT between Thin and Tcin may affect the values of the rate of heat transfer (qact and qmax) and the heat transfer rate will affect the effective efficiency performance of heat exchangers. The highest qact value that is equal to 276,752 Btu/h with Cc at 0,00737 Btu/hr.°F, and the lowest was qact of 4,822 Btu/h with Cc at 0,00028 Btu/hr.°F. The highest qmax value is 479,193 Btu/h with Ch 0,00562 Btu/hr.°F, and qmax low of 7,715 Btu/h with Ch 0,00023 Btu/hr.°F. And the value of the highest effective efficiency it est 62,50% with qact of 4,822 Btu/h and qmax of 7,715 Btu/hr, the data obtained from the difference in value (qmax - qact) of 2,893 Btu/hr. While the lowest efficiency is 46,67% with qact of 6,862 Btu/h and qmax of 14,705 Btu/hr, the data obtained from the difference in value (qmax - qact) of 7,843 Btu/hr. And it can be concluded that the smaller the heat of hot fluid (Ch) then it will be getting smaller also the the maximum heat transfer rate (qmax) happens, and vice versa if the greater heat fluid type then the greater the maximum heat transfer rate also happens. Conditions affecting the high and low effective efficiency heat exchanger is the difference in value between the actual heat transfer rate (qact) and the maximum heat transfer rate (qmax). The greater the difference in value then the smaller the effective efficiency, and if the smaller the difference in value then the greater the effective efficiency.