Vanes, turbine

Turbinenschaufel, /. turbine vane or blade. turbinieren, v.t. centrifuge. 

Aluminium diffusion calorising, aluminisingY protects steels against oxidation at elevated temperatures, and the more recently developed processes for aluminising and chromaluminising superalloys are widely used to increase the life and operating temperature of aircraft gas turbine vanes, etc. 

Fig. 6.6. Power number versus Reynolds number for various impellers (flat blades, turbine, vaned disk and marine propeller).

In this chapter we will illustrate and analyze some of the more common methods for measuring flow rate in conduits, including the pitot tube, venturi, nozzle, and orifice meters. This is by no means intended to be a comprehensive or exhaustive treatment, however, as there are a great many other devices in use for measuring flow rate, such as turbine, vane, Coriolis, ultrasonic, and magnetic flow meters, just to name a few. The examples considered here demonstrate the application of the fundamental conservation principles to the analysis of several of the most common devices. We also consider control valves in this chapter, because they are frequently employed in conjunction with the measurement of flow rate to provide a means of controlling flow. 

Disc-type turbines In this type of turbines, blades can be straight or curved. In the related literature, the term straight is some times replaced by the term flat. The most popular turbine of this type is the straight-blade disc turbine, which is better known as the Rushton turbine (Figure 3.18). The same turbine is also called flat-blade turbine, vaned disc or simply flat-blade turbine. ... 

PSZ is one of the most popular refractory materials and used as a thermal barrier coating material in combustion chamber and/or turbine vanes of jet engines. INIOO is also used widely as a material of turbine blades and vanes. For this reason, FGM of PSZ/INIOO was selected. 

For the past 15 years, research and development of CMCs has been sustained because of their potential for military and commercial applications. The applications of interest include (1) aircraft engine components, such as combustors, turbines, compressors and exhaust nozzles (2) ground-based and automotive gas turbine components, such as combustors, first and second stage turbine vanes and blades, and shrouds (3) aerospace engines for missiles and reusable space vehicles and (4) industrial applications, such as heat exchangers, hot gas filters, and radiant burners. 

Land-based gas turbines United States power generation combustor turbine vanes l,600°C(2,912°F)for > 25,000 hrs... 

The effects of surface roughness, curvature of impingement surface, and artificially induced turbulence have been studied primarily with regard to their application in turbine vane cooling rather than drying (see Refs. [26-28]). 

Ceramics Protective plates for gliders Valves, turbine vanes Piston head, piezo actors... 

The general low resistance to oxidation of carbon only permits restricted operational periods of the C/SiC structures at temperatures above about 450 °C. Its utilization in civil aircraft turbines or stationary gas turbines (e.g. as tiles in combustion chambers, for diffusers or for turbine vanes) with operational times of several 10,000 hours is therefore not possible... 

Oxidative stability of surface coated SiC/RBSN monofilament composites in burner rig testing prompted interest in utilization of this composite for uncooled components for small engine applications. Turbine vanes were machined from blanks of 1-D and 2-D SiC/RBSN composites, and surface coated with a layer of CVD SiC and glass former. Both uncoated and coated vanes were engine tested in at 1315°C for 10 h. The uncoated vanes showed severe damage, but the surface coated vanes survived engine tests with minimal damage [28]. 

Coatings of refractory carbides and nitrides have great industrial importance with a wide range of applications in semiconductors and other electronic components, in cutting tools, gas-turbine vanes and blades, precision bearings, punch sets, extruders, prostheses, and many other products. 

If the turbine vanes and combustion zones of jet aircraft engines can withstand higher working temperatures the engine efficiency is improved. Such an effect is obtained if 1-2% Hf is added to the nickel-based superalloys. 

An adhering deposit may be made more freely running and removed more easily if ammonia is introduced into a fuel-oil boiler [462]. Particularly serious complications arise in the burning of fuel oil in gas turbines, when the ash sticks to the vanes of the turbine. By adding substances containing silicon, aluminum, magnesium, and zinc compounds to the heavy fuel oils used for this purpose, the melting point of the ash is considerably raised and its tackiness is thereby reduced. It is also recommended in [463] that up to 0.15% kaolin powder should be added to the fuel oil this ensures the formation of loose, easily removed deposits and reduces the adhesion of particles to the turbine vanes by a factor of several times. 

Carryover from boilers can be defined as the presence of water in the steam leaving the boiler. This water contains solids that cause deposit and corrosion problems in the postboiler system, one of the more serious of which is the rapid build-up of silica deposits on turbine blades. The sflica concentrations are so critical that saturated steam is not safe for turbine vanes unless it contains less than 10 to 15 ppb SiOj . The problem of silica deposits on turbine blades is primarily present under high-pressure conditions, whereas at lower pressures a considerable amount of SiOjCan be tolerated in the boiler water. At pressures over about 27 to 41 bars (400 to 600 psig), silica in the boiler water... 

Aerospace assemblies (turbine vanes, filters, high pressure pump bodies) Automotive assemblies (crankshaft, gears, valves, bearings)... 

Cooling holes on high-pressure turbine vanes. 

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