Duty, effectiveness and area for a heat exchanger.
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Design and analyze shell-and-tube or double-pipe heat exchangers using NTU-effectiveness method
Fluid temperatures along exchanger length
Performance curve for current Cr = 0.67
• Reynolds Number: Re > 10,000 for turbulent flow (better heat transfer). Re < 2,300 is laminar.
• Tube Velocity: Typically 1-3 m/s for liquids to balance heat transfer and pressure drop.
• Shell Velocity: Typically 0.5-1.5 m/s for liquids on shell side.
• Fouling Factors: Clean water ~0.0001, cooling tower water ~0.0003, heavy fuel oil ~0.0009 m²·K/W
• NTU: NTU > 3-4 gives diminishing returns on effectiveness (80%+ typically achievable).
• Calculations: Using Dittus-Boelter for tube-side, Kern method approximation for shell-side.