Review of P J Potter's Power Plant Theory and Design
P J Potter's Power Plant Theory and Design is a classic textbook on the principles and applications of steam power plants. The book covers topics such as fluid mechanics, thermodynamics, heat transfer, combustion, turbines, boilers, condensers, pumps, and generators. The book also includes examples, problems, tables, and diagrams to illustrate the concepts and calculations.
The book was first published in 1959 under the title Steam Power Plants[^2^], and has been revised and reprinted several times since then. The latest edition was published in 1988 by R.E. Krieger[^1^]. The book is suitable for undergraduate and graduate students of mechanical engineering, as well as practicing engineers and researchers in the field of power generation.
P J Potter's Power Plant Theory and Design is a comprehensive and authoritative reference for anyone interested in the design and operation of steam power plants. The book provides both theoretical and practical knowledge on the subject, and is widely regarded as one of the best books on power plant engineering.
The article will now discuss the different types of steam turbines and their design and operation features.
Types of steam turbines
Steam turbines can be classified according to the direction of steam flow, the number of stages, the degree of reaction, and the extraction and induction modes.
Direction of steam flow
Steam turbines can have axial or radial flow configurations. In axial flow turbines, the steam flows parallel to the axis of rotation of the rotor. In radial flow turbines, the steam flows perpendicular to the axis of rotation. Axial flow turbines are more common and efficient than radial flow turbines, especially for large power outputs. Radial flow turbines are mainly used for small power outputs and high pressure ratios.
Number of stages
A stage of a steam turbine consists of a set of stationary blades (also called nozzles or stators) and a set of rotating blades (also called buckets or rotors) attached to a shaft. The stationary blades accelerate and direct the steam toward the rotating blades, which extract work from the steam by changing its momentum and pressure. The number of stages in a steam turbine depends on the pressure and temperature of the inlet steam, the pressure of the exhaust steam, and the desired power output. Generally, higher pressure ratios and lower power outputs require fewer stages, while lower pressure ratios and higher power outputs require more stages.
Degree of reaction
The degree of reaction (R) of a stage is defined as the ratio of the enthalpy drop (or heat transfer) in the rotating blades to the total enthalpy drop in the stage. The degree of reaction can vary from 0 to 1. If R = 0, then all the enthalpy drop occurs in the stationary blades, and the rotating blades only change the direction of the steam. This is called an impulse stage. If R = 1, then all the enthalpy drop occurs in the rotating blades, and the stationary blades only change the direction of the steam. This is called a reaction stage. If 0 < R < 1, then some enthalpy drop occurs in both the stationary and rotating blades. This is called an impulse-reaction stage.
Extraction and induction modes
Some steam turbines have extraction ports that allow some steam to be extracted at intermediate pressures for process heating or feedwater heating purposes. These are called extraction turbines (Figure 1c). Extraction turbines can improve the overall thermal efficiency of a steam power plant by reducing the heat loss in the condenser. Some steam turbines have induction ports that allow some steam to be added at intermediate pressures from another source. These are called induction turbines (Figure 1d). Induction turbines can increase the power output of a steam power plant by utilizing excess or waste steam from another process. 061ffe29dd