Influence of Plate Width at Plate Heat Exchanger Evaporator Design for Organic Rankine Cycle with Heat Source Temperature of 70°C

Evaporator in Organic Rankine Cycle (ORC) system is used to convert the working fluid phase of pump output from liquid to vapor as a turbine input. Evaporator performance has an effect to ORC performance. This paper discusses the design of Plate Heat Exchanger (PHE) type as ORC evaporator which is utilized to vaporize the working fluid (R227ea) liquid phase at temperature and pressure of 35°C and 10 bar into saturated vapor phase at temperature of 53.42°C. Water was used as heating fluid with temperature and flow rate of 70°C and 2806 kg/h. PHE was designed by determining the constant and independent variables of PHE dimensions, calculating evaporator capacity, estimating the overall heat transfer coefficient, calculating heat transfer area and the pressure drop. The independent variable is PHE plate width(0.15m, 0.30m, and 0.45 m). The design result that the rise of plate width will increase total heat transfer area (1.44 m
²
, 1.62 m
²
, 1.89 m
²
, respectively). In the other side, the rise of plate width will decrease the total pressure drop to 0.13 bar, 0.04 bar, 0.02 bar (R227ea side) and 1.28 bar, 0.43 bar, 0.24 bar (water side).