Home Bücher eBücher Zeitschriften Referenzen und Berichte Autoren, Herausgeber, Rezensenten A – Z Produktindex Auszeichnungen
Thermisches Design von luftgekühlten Wärmetauschern in der Praxis – 壳管换热器的实用热设计

ISBN:
978-1-56700-245-4 (Druckformat)

Thermisches Design von luftgekühlten Wärmetauschern in der Praxis – 壳管换热器的实用热设计

Beschreibung

The thermal design of air-cooled heat exchangers is a fascinating activity—sometimes even more so than that of shell-and-tube heat exchangers—for the simple reason that there are more variables: even the coolant (air) flow rate is a variable! This book will have served its purpose if it can inspire the reader to consider the thermal design of air-cooled heat exchangers as a joyous activity rather than a mundane chore.



142 pages, © 2007

Inhaltsverzeichnis:

Dedication
Acknowledgments
About the Author
Preface
Chapter 1 Introduction
Chapter 2 Advantages and Disadvantages of Air Cooling
2.1 Advantages of Air Cooling
CASE STUDY 2.1 EFFECT OF REDUCTION OF AIR FLOW RATE
2.2 Disadvantages of Air Cooling
Chapter 3 Optimization of Air and Water Cooling
CASE STUDY 3.1 SELECTION OF DESIGN AMBIENT TEMPERATURE FOR AIR AND WATER COOLING
Chapter 4 Construction Features of Air-cooled Heat Exchangers
4.1 Introduction
4.2. Tube Bundle
4.2.1 Finned tube
4.2.2 Headers
4.2.3 Tube supports
4.2.4 Side frames
4.2.5 Tube-to-tubesheet joint
4.3 Fans and Drives
4.3.1 Fans
4.3.2 Fan drives
4.3.3 Plenum chamber
4.4 Configuration of ACHEs
4.5 Natural Draft versus Mechanical Draft
4.6 Forced Draft versus Induced Draft
Chapter 5 Thermal Design of Single-Phase Air-cooled Heat Exchangers
5.1 Introduction
5.2 Broad Objectives of Thermal Design
5.3 Data to Be Furnished for Thermal Design
5.4 Tubeside Calculations
5.4.1 Effects of tubeside velocity
5.4.2 Tubeside heat transfer coefficient
CASE STUDY 5.1 HIGH-PRESSURE GAS COOLER
CASE STUDY 5.2 LOW-PRESSURE GAS COOLER
5.4.3 Tubeside pressure drop
5.4.4 Increased tubeside pressure drop
CASE STUDY 5.3 EFFECT OF ALLOWABLE TUBESIDE PRESSURE DROP-FIRST STUDY
CASE STUDY 5.4 EFFECT OF ALLOWABLE TUBESIDE PRESSURE DROP- SECOND STUDY
5.5 Airside Calculations
5.6 Mean Temperature Difference
5.7 Design Ambient Temperature
CASE STUDY 5.5 EFFECT OF DESIGN AMBIENT TEMPERATURE
5.8 Noise
Chapter 6 Thermal Design of Condensing Air-Cooled Heat Exchangers
6.1 Introduction
6.2 Classification of Air-Cooled Condensers
6.2.1 According to service
6.2.2 According to condensing range
6.2.3 According to operating pressure
6.3 Mechanisms of Condensing
6.3.1 Vertical in-tube condensation
6.3.2 Horizontal in-tube condensation
6.3.3 Condensation of mixed vapors and mixtures of vapors and noncondensables
6.4 Some Case Studies
CASE STUDY 6.1 ISOTHERMAL CONDENSER
CASE STUDY 6.2 NARROW-RANGE CONDENSER
CASE STUDY 6.3 WIDE-RANGE CONDENSER
CASE STUDY 6.4 THE EFFECT OF PRESSURE ON AIR-COOLED CONDENSERS
6.5 Condensation with Desuperheating and/or Subcooling
6.5.1 Desuperheating
CASE STUDY 6.5 CONDENSATION WITH DESUPERHEATING
6.5.2 Subcooling
6.6 Nozzle Sizing
6.7 Condensing Profiles and MTD
Chapter 7 Optimization of Thermal Design of Air-Cooled Heat Exchangers
7.1 Tube Length
7.2 Tube OD
CASE STUDY 7.1 OPTIMIZATION OF TUBE OD
7.3 Fin Height
CASE STUDY 7.2 OPTIMIZATION OF FIN HEIGHT: AIRSIDE HEAT TRANSFER COEFFICIENT CONTROLLING
CASE STUDY 7.3 OPTIMIZATION OF FIN HEIGHT: TUBESIDE HEAT TRANSFER COEFFICIENT CONTROLLING
7.4 Fin Spacing
CASE STUDY 7.4 VARIATION OF AIRSIDE HEAT TRANSFER COEFFICIENT AND PRESSURE DROP WITH FIN DENSITY
7.5 Number of Tube Rows
7.6 Fan Power Consumption
CASE STUDY 7.5 OPTIMIZATION OF FAN POWER CONSUMPTION
7.7 Tube Pitch
CASE STUDY 7.6 EFFECT OF TUBE PITCH AND FIN DENSITY ON AIRSIDE HEAT TRANSFER COEFFICIENT AND PRESSURE DROP
7.8 Number of Tube Passes
CASE STUDY 7.7 OPTIMIZATION OF TUBE PASS DISTRIBUTION
Chapter 8 Physical Properties and Heat Release Profiles
8.1 Physical Properties
8.2 Physical Property Profiles
8.3 Heat Release Profiles
8.4 How to Feed Heat Release Profiles
Chapter 9 Overdesign
9.1 Introduction
9.2 Mechanics of Overdesign
9.3 Overdesign in Single-Phase Heat Exchangers
CASE STUDY 9.1 EFFECTS OF OVERDESIGN-HIGH OVERDESIGN CASE
9.4 Overdesign in Condensers
CASE STUDY 9.2 EFFECTS OF OVERDESIGN-LOW OVERDESIGN CASE
9.5 The Overdesign Factor
9.6 Tube Plugging
Chapter 10 Fouling-Its Causes, Consequences, and Mitigation
10.1 Tubeside Fouling
10.1.1 Categories of fouling
10.1.2 Progress of fouling
10.1.3 Parameters that affect fouling
10.1.4 How to provide a fouling allowance
10.1.5 Selection of fouling resistance
10.1.6 Design guidelines to minimize tubeside fouling
CASE STUDY 10.1 MAINTAINING HIGH TUBESIDE VELOCITY
CASE STUDY 10.2 USING A FOULING LAYER THICKNESS ON THE TUBESIDE
10.2 Airside Fouling
CASE STUDY 10.3 USING A FOULING LAYER THICKNESS ON THE AIRSIDE
Chapter 11 Control of Air-Cooled Heat Exchangers
11.1 Introduction
11.2 Methods of Control
11.2.1 Bypassing of process fluid
11.2.2 Switching fans on/off
11.2.3 Use of two-speed motors
11.2.4 Use of louvers
11.2.5 Use of autovariable fans
11.2.6 Use of variable frequency drives
Chapter 12 Operating Problems in Air-Cooled Heat Exchangers
12.1 Introduction
12.2 Problems on the tubeside
12.2.1 Flow maldistribution
12.2.2 Inadequate process cooling
12.2.3 Excessive fouling
12.3 Operating Problems on the Airside
12.3.1 High air inlet temperature
12.3.2 Hot air recirculation
12.3.3 Inadequate air flow
12.3.4 Incorrect selection of design ambient temperature
12.3.5 High noise level
12.3.6 Airside fouling
12.4 Performance Evaluation of Air-Cooled Heat Exchangers
Chapter 13 Special Applications
13.1 Combined Services
CASE STUDY 13.1 COMBINED SURFACES
13.2 Recirculation Air-Cooled Heat Exchangers
13.3 Humidified Air-Cooled Heat Exchangers
13.4 Use of Tube Inserts
CASE STUDY 13.2 USE OF WIRE-FIN TUBE INSERTS
13.5 Use of Variable Finning Density
CASE STUDY 13.3: USE OF VARIABLE FINNING DENSITY
13.6 Use of Natural Draft
CASE STUDY 13.4 USE OF NATURAL DRAFT
13.7 Air-Cooled Vacuum Steam Condensers
Index