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Contents
5.6.3 Measurement Procedure ....................................................... 183
5.6.4 Calculations .......................................................................... 184
5.6.5 Measurement Example ......................................................... 184
5.7 Laboratory Test of a Centrifugal Fan ............................................... 184
5.7.1 Test Rig ................................................................................ 184
5.7.2 Measurements ...................................................................... 187
5.7.3 Measurement Procedure ....................................................... 187
5.7.4 Calculations .......................................................................... 188
5.7.5 Measurement Example ......................................................... 188
5.8 Laboratory Test of a Centrifugal Pump ............................................ 189
5.8.1 Test Rig ................................................................................ 189
5.8.2 Measurements ...................................................................... 190
5.8.3 Measurement Procedure ....................................................... 190
5.8.4 Calculations .......................................................................... 191
5.8.5 Measurement Example ......................................................... 192
6 Steam Turbines ........................................................................................ 193
6.1 Applications of Steam Turbines ....................................................... 193
6.2 Working Principles of Steam Turbines ............................................. 195
6.3 The Steam Cycle .............................................................................. 199
6.4 The Single Impulse Stage or Laval Stage ........................................ 200
6.4.1 Velocity Triangles ................................................................. 200
6.4.2 Work and Energy Relations .................................................. 201
6.4.3 Stage Efficiency Definitions ................................................ 204
6.4.4 Blade Profile Shape .............................................................. 205
6.4.5 Loss Representation ............................................................. 208
6.4.6 Optimisation of Total-to-Static Efficiency ........................... 209
6.5 The Pressure-Compounded Impulse Turbine
or Rateau Turbine ............................................................................. 212
6.5.1 Principle ............................................................................... 212
6.5.2 Efficiency ............................................................................. 213
6.6 The Velocity-Compounded Impulse Turbine or Curtis Turbine ....... 214
6.7 The Reaction Turbine ....................................................................... 217
6.7.1 Degree of Reaction ............................................................... 217
6.7.2 Efficiency ............................................................................. 218
6.7.3 Axial Inlet and Outlet ........................................................... 222
6.8 Steam Turbine Construction Forms ................................................. 224
6.8.1 Large Steam Turbines for Power Stations ............................ 224
6.8.2 Industrial Steam Turbines .................................................... 229
6.9 Blade Shaping .................................................................................. 231
6.9.1 HP and IP Blades .................................................................. 231
6.9.2 LP Blades ............................................................................. 233
6.10 Exercises ........................................................................................ 236
References ................................................................................................. 246