Correlating Parameters of Heat Exchange in Condensers Leif

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Correlating Parameters of Heat Exchange in Condensers Leif Burgess, Nick Schedeler, Ryan Lamers Introduction

Correlating Parameters of Heat Exchange in Condensers Leif Burgess, Nick Schedeler, Ryan Lamers Introduction Results Design Problem • The heat transfer coefficient increased with cold stream flow rate for all trials except parallel flow in the Allihn condenser • Determine outlet temperature, and inner/outer diameter 600 SCFM Steam Water Th, i = 100˚C • The Liebig condenser has a larger overall heat transfer coefficient then the Allihn condenser and is therefore more effective. Th, o = 100˚C Tc, o • The effect of condenser type and flow pattern on the overall heat transfer coefficient (U) was analyzed using the following: Tc, i = 15˚C Water out 1200 Water in (1) (2) Methods U (W/m 2∙s) 1050 U (W/m 2∙s) • Reynold’s number (NRe) was used to correlate relevant parameters of our system to the overall heat transfer coefficient 400 900 Parallel Counter 750 600 Allihn 300 250 200 7558. 6 300 5. 0 E-06 1. 0 E-05 1. 5 E-05 2. 0 E-05 2. 5 E-05 3. 0 E-05 3. 5 E-05 400 U (W/m 2∙s) Figure 3: For the Liebig condenser, as the flow rate of the cold stream increased the overall heat transfer coefficient increased as well. The magnitude of this correlation was greater for counter flow. Counter Flow Figure 1: Condensers studied in experiment 350 200 0 350 U (W/m 2∙s) Condensation point Water out 300 Parallel Counter 250 Compare cold stream flow rate to max U Calculate Di Steam 150 5. 0 E-06 1. 0 E-05 1. 5 E-05 2. 0 E-05 2. 5 E-05 3. 0 E-05 3. 5 E-05 Flow Rate (m 3/s) Figure 4: For the Allihn condenser, as the flow rate of the cold stream increased the overall heat transfer coefficient increased with counter flow and decreased with parallel flow. Figure 2: Process Flow Diagram 2000 4000 Reynold’s Number of Cold Stream Figure 6: Dimensionless comparison to the overall heat transfer coefficient for the hot flow stream 200 Water in Parallel Counter 300 400 • Cold Stream Flow Rates (m 3/s): 9. 58∙ 10 -6, 2. 08 ∙ 10 -5, 3. 29 ∙ 10 -5 • Flow rates were tested in triplicate h 8058. 6 8558. 6 9058. 6 Reynold’s Number of Hot Stream Figure 5: Dimensionless comparison to the overall heat transfer coefficient for the hot flow stream Flow Rate (m 3/s) Parallel Flow Parallel Counter 450 • Measured Variables: inlet/outlet temperatures, heat transfer area, flow rates Liebig 350 Calculate Do Use Eq. 1 to calculate Tc, o • Final Answers: Inner Diameter= 38. 195 mm , Do= 38. 199 mm, & Tc, o= 16. 59˚C References Transport Processes and Separation Process Principles, 4 th ed. , Prentice-Hall, Inc. Upper Saddle River, NJ, 2003, pp. 291 -300.