Heat Transfer Enhancement in Corrugated Plate Heat Exchanger

Background of the Problem: Heat exchanger is a device in which heat transfer occurs from hot fluid to cold fluid and vice versa; It is used for many applications particularly for process industries. Plate type heat exchanger gives better solution in terms of heat transfer, when compared with different types of heat exchangers. Design pressure is less than 20 bar, while design temperature is less than 180°C for a plate heat exchanger. Little reports were available on heat transfer analysis of corrugated plate heat exchanger with variation of viscosity of fluid and corrugation angle.

Aim: Investigations were carried out to determine heat transfer rate of corrugated plate heat exchanger with varied corrugation angles of 30°, 40° and 50° with varied test fluids of water, 10% glycerin, 20% glycerin and 30% glycerin.

Methodology: A single corrugation pattern on three plates arranged in parallel with varied chevron angles with spacing between the plates was 5 mm. Cold water/10% glycerol solution/20% glycerol solution/ and 30% glycerol solution were used as cold fluids, with the flow being counter flow. Hot water at 70°C at constant flow rate was used for heating the test fuels.

Design Variables: Test fluids of different viscosities and corrugation angles.

Brief Results: It was observed that heat transfer coefficient was higher for a given Reynolds number for 50° corrugation angle compared to other corrugation angles of 30° and 40°. By using Regression analysis, a new correlation was developed for corrugated plate heat exchanger for the prediction of Nusselt number, which was a function of Reynolds number, Prandtl number and corrugation angle. Nusselt number predicted by correlation was correlated with experimental result, which was deviated by 8% only from actual experimental result. Also the correlation was compared with that of other researchers in order to validate the data.