Multi-stage turbine

The majority of centrifugal pumps have performance curves with the aforementioned profiles. Of course, special design pumps have curves with variations. Eor example, positive displacement pumps, multi-stage pumps, regenerative turbine type pumps, and pumps with a high specific speed (Ns) fall outside the norm. But you ll find that the standard pump curve profiles are applicable to about 95% of all pumps in the majority of industrial plants. The important thing is to become familiar with pump curves and know how to interpret the information. 

Nishida K., Takagi T., Kinoshita S., Tsuji T. (2002) Performance evaluation of multi-stage SOFC and gas turbine combined systems. In Proceedings of the ASME Turbo Expo, Amsterdam, the Netherlands, GT-2002-30109. 

A turbomolecular pump is a multi-stage, bladed turbine in which the rotor is driven at high rotational speeds so that the peripheral speed of the blades is of the same order of magnitude as the thermal velocity (c) of the gas particles to be pumped. The combination of a rotor and stator disc is one stage in a TMP. Pumped gas is compressed along the rotor-stator assembly and passed to a backing pump/pump-set for further compression to atmospheric pressure. 

Some of the options available for selecting a steam turbine are as follows. These could be in single stage or multi stage construction. Further details can be dis-cussed/obtained from the vendors concerned to suit the specific requirements on site... 

The use of multi-stage gas turbine with reheat(s) may represent a possible alternative to improve the thermodynamic cycle performance, but state-of-the-art gas turbines need to... 

The argument developed in Section 4.2.1.2 can be extended for three or more steps of cooling, to give the same efficiency as the uncooled cycle. Indeed the efficiency will be the same for multi-step cooling, with infinitesimal amounts of air abstracted at an infinite number of points along the compressor to cool each infinitesimal turbine stage at the required pressures. 

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