Download Heat Transfer: transfer of energy from one object to another

5/24/2013
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Heat Transfer: transfer of energy from one object to another
Direction: hot to cold
British Thermal Unit (BTU): one degree of F per pound of water
Calorie: one degree C per gram of water
Three Methods: conduction, convection, radiation, Figure 11-1
Heat Transfer Coefficients: rate increase
-- temperature difference
-- surface area
-- heat transfer coefficient
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Other factors for heat transfer rate:
-- fouling
-- flow types
Countercurrent flow, Figure 11-2
Co-current flow, Figure 11-3
Parallel flow: Figure 11-4
Cross flow: Figure 11-5
Flow Regimes: Laminar (streamline), Figure 11-6
Turbulent, Figure 11-7, baffles
Reynolds number
Types of Heat Exchangers
Double-pipe, Figure 11-8
Spiral, Figure 11-9
Shell and Tube, Figure 11-10, 11-11
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Multi pass, Figure 11-12, 11-13
U-tube (hairpin), Figure 11-14
Plate and Frame: Figure 11-15
Components of Heat Exchanger, Figure 11-17
Tube bundle
Shell
Exchanger head
Plain tubing, Figure 11-18
Tube sheet
Exchanger Applications and Services
Preheater
Reboiler
Condenser, Figure 11-19
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Potential Problems: Deviations
-- excessive pressure drop, loss of flow, lower of heat transfer,
likelihood of fouling
Safety and Environmental Hazards: Table 11-1, 11-2
Typical Procedures: Page 22--229
Startup
Shutdown
General Maintenance Tasks
Backwashing (back-flushing)
Technician’s Role: Table 11-3
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