Power Plant Engineering

360 POWER PLANT ENGINEERING beauty of landscape. The overall cost is further reduced by the modern techniques in tunnel work and ...

HYDRO-ELECTRIC POWER PLANTS 361 The choice of the site for the power house either over ground or underground requires a consid- ...

362 POWER PLANT ENGINEERING of both surge tanks can be calculated independently according to the usual surge theory. If the prim ...

HYDRO-ELECTRIC POWER PLANTS 363 As per the action of water on the prime-mover, they are classified as impulse turbine and reacti ...

364 POWER PLANT ENGINEERING With the turgo impulse turbine, the jet is set at an angle to face the runner, strikes the buckets a ...

HYDRO-ELECTRIC POWER PLANTS 365 runner. It is obvious from the figures that the flow through the runner changes from radially in ...

366 POWER PLANT ENGINEERING The rotor of the Kaplan turbine is shown in Fig. 11.23. The blades are rotated to the most effi- cie ...

HYDRO-ELECTRIC POWER PLANTS 367 The inspection and overhaul of a Francis is much more difficult job than that of the equivalent ...

368 POWER PLANT ENGINEERING Substituting the value of Q in the above equation, we get P ∝ 75 ρ 3/ 2 2 ()H N    H ∝ 5/2 2 ( ...

HYDRO-ELECTRIC POWER PLANTS 369 high specific speed reaction runner would reduce the size of the runner to such an extent that t ...

370 POWER PLANT ENGINEERING 11.12 Draft Tubes Reaction turbines must be completely enclosed because a pressure difference exists ...

HYDRO-ELECTRIC POWER PLANTS 371 Pa A H 0 H pa h B C D E hd Fig. 11.26 Ea = Eb = H + hd + pa ρ Ec = h +hd + 2 2 Vc g + c p ρ Ed = ...

372 POWER PLANT ENGINEERING Comparing the equations (a) and (b) the extra work done per kg of water due to draft tube is given b ...

HYDRO-ELECTRIC POWER PLANTS 373 Cavitation and Limitation of Turbine Height above Tailrace Level. The formation of water vapour ...

374 POWER PLANT ENGINEERING where Ha = Atmospheric pressure head in meter of water Hv = Vapour pressure in metre of water corres ...

HYDRO-ELECTRIC POWER PLANTS 375 Table 11.7. (NsVsσσσσσs) Francis Kaplan Ns sc Ns σσσσσc 50 0.04 300 to 450 0.35 to0.40 100 0.05 ...

376 POWER PLANT ENGINEERING (2) Elbow Type Draft Tube. The elbow type draft tube is often preferred in most of the power plants, ...

HYDRO-ELECTRIC POWER PLANTS 377 D Ta i l r a c e 5° (2.5 to3)D (0.6 to1)D ( ) Conical draft tubea ( ) Trumpet shaped draft tubeb ...

378 POWER PLANT ENGINEERING In high head plants (using reaction turbine as prime mover), where the velocity in the draft tube ma ...

HYDRO-ELECTRIC POWER PLANTS 379 N = 60 πD . V = 60 πD 2 gH ∴ N ∝ (^) H ∴ N = K 2 H where K 2 is the coefficient which varies wit ...