Aircraft Propulsion and Gas Turbine Engines 1st. Edition by Ahmed F. El-Sayed | 9780849391965 | 0849391962 | Holooly

Aircraft Design

Aircraft Propulsion and Gas Turbine Engines

98 SOLVED PROBLEMS

Question: 15.3

An IFR turbine with 12 vanes is required to develop 229.6 KW from a supply of hot gases available at stagnation temperature of 1000 K and a flow rate of 1 kg/s. It has the following data: Ca3/U2 = 0.25, ζ = 0.4, r3s/r2 = 0.7, and W3m/W2 = 2.0 Total-to-static efficiency 0.85 Static pressure at rotor ...

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Whitefield equation

\cos^2 \alpha_2=\frac{1...

Question: 12.3

An aircraft engine is fitted with a single-sided centrifugal compressor. The aircraft flies at a Mach number 0.85 and at an altitude of 35,000 ft. The inlet duct of the impeller is fitted with IGV. The hub and shroud diameters of the eye are 14 and 28 cm, respectively, and the rotational speed is ...

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The given data are

d_{\text{eh}}=14 \text{ ...

Question: 16.2

The following data refer to a gas turbine with a free power turbine, operating at design speed. ...

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For chocked free turbine

\dot{m}\sqrt{T_{04...

Question: 15.2

A radial inflow turbine has the following characteristics and operating conditions: Inlet total temperature 1400 K Inlet total pressure 3.0 bar Rotor tip rotational speed 500 m/s Rotational speed 40,000 rpm Specific speed ΩS ≡ 1.131√Q3 / N D³2 = 0.58 β3av = 63°, D3s/D2=0.7, α2 = 74° D3h/D3s=0.4, ...

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(a) Total-to-static efficiencyFrom Figure 15.5, wi...

Question: 14.6

An axial turbine stage is to be designed by a constant nozzle design. It has the following data: ΔT0 = 150 K, U2h = 300 m/s, U2t = 400 m/s, α2 = 60, α3 = 0, and ζ3 = 0.75 (a) Draw the velocity triangles at the hub, mean, and tip sections. (b) Use the approximate solution for the constant nozzle ...

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(a) Constant nozzle angle designThe axial turbine ...

Question: 14.4

An axial turbine has the following data: ζ = 0.8, α2m = 60, α3 = 0, Λm = 0.5 and Cam = 200 m/s Three design methods are to be examined. The governing equations for each are as follows: Method (1) Cu2m = Cu2h Method (2) Ca2t / Ca2h = ζ ^ sin ²α2 Method (3) Cu2t / Cu2h = ζ It is required to 1. ...

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Given data

\zeta=0.8, \quad \alpha_3=0 , \q...

Question: 14.5

(A) Two design methods are used in an axial turbine design. The swirl velocity at radius (r) in the first method is (Cu) and swirl velocity at the same radius (r) in the second method is (C′u). If the ratio between two swirl velocities is given by the ratio ...

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(a)(1) For general power with N = 1 at radius (r),...

Question: 14.1

Consider a three-stage axial flow turbine where the total inlet temperature is 1100 K, the flow coefficient is 0.8, and the mean rotational speed is constant for all stages and equal to 340 m/s. ...

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1. The sketch (Figure 14.14) illustrates the three...

Question: 13.7

A seven-stage axial compressor has the following data: Overall pressure ratio 4.15 , Mean rotational speed 266 m/s , Axial velocity 150 m/s , Stage efficiency 0.9 , Inlet temperature and pressure are 288 K, 101 kPa. Calculate the following variables for each stage: πs , ΔT0s , α1 , β1 , α2 , β2 , ...

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The total temperature rise for the compressor is c...

Question: 13.10

The compressor in a single-spool turbojet engine is composed of a four-stage axial compressor and a single-stage centrifugal compressor. The rotational speed is 290 rev/s. The detailed data of both compressors are given as Axial compressor (A): Temperature rise per stage 25 K Polytropic efficiency ...

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(a) The temperature difference across these compre...

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