Fluid mechanics and thermodynamics of turbomachinery Upplaga 4

Turbomachines are those in which energy is transferred to or from a continuously moving fluid by the motion of a rotating element. Some of the most common and important machines used in engineering and industry fall into this category, including those which absorb power (and thereby increase fluid pressure), such as fans, compressors and pumps. Also included are equally vital varieties of machines which generate power from the expansion of fluids to lower pressures such as hydraulic, steam and gas turbines. This general definition embraces a number of devices that are classified as 'open', such as propellers, windmills and unshrouded fans. The machines examined here are those defined as 'closed', where a finite quantity of fluid can be considered to pass through the machine in unit time, for it is these which are of the most interest to students and professionals in the fields of mechanical, chemical, and plant engineering. It is in these areas that the devices that form the subject matter of this book find their most important applications, making this treatment of vital importance to anyone working in or studying them. Example questions and answers throughout Includes more new material on axial flow compressors and pumps