ISSN:
1570-1468
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Energietechnik
Notizen:
Conclusions 1. It is recommended that the length of the mixing chamber Lmix.ch and the distance x between the shroud section and the mouth of the mixing chamber be set equal for high-head ejectors (Lmix.ch = 6–7Dmix.ch, x = dn); Lmix.ch = 7Dmix.ch and x = 0.5dn for medium-head ejectors; and, Lmix.ch = 7–8Dmix.ch and x = 0.3dn for low-head ejectors; here, Dmix.ch is the diameter of the mixing chamber, and dn is the nozzle diameter. 2. It is recommended that the length of the inlet to the mixing chamber be set equal to Lin = 0.5Dmix.ch. In this case, the following relationships are necessary for the ejectors: x/Lin ∼ 1.00, x/Lin ∼ 0.50, and x/Lin ∼ 0.15 for high-, medium-, and low-head ejectors, respectively. 3. It is recommended that the nozzle be constructed with a cylindrical section (with respect to the inside diameter at the outlet) with a length 0.5dn. 4. It is recommended that the intake flow be delivered at 90° to the ejector axis so that the inner edge of the supply line coincides (or nearly so) with the nozzle section. Smooth delivery of the intake flow in numerical terms does not yield a gain in delivery, but is less economical in terms of technical and structural considerations. 5. It is recommended that the diffusor be constructed with a constant 8° taper angle. A sectional diffusor did not offer any apparent advantages in terms of ejector delivery during the experiment. The expediency of its use for ejectors of various head capacities h, the required number of sectional diffusor parts, and the magnitude of the taper angle in each section will therefore require special study. Experimental studies conducted at the Bratsk hydroelectric plant provided ample information to assess the operation of ejectors used for commercial water supply under rated and nonrated head conditions. This work can be considered one of the stages in the development of a general method for ejector design.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF02304346
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