1. A 75 m high wind tower with a 50 m rotor diameter has been constructed in a region that follows the 1/7th rule for the coefficient of shear friction. The blades that have been selected for the turbine can reliably operate over a prolonged period of time if the maximum power ratio experienced during each blade rotation does not exceed 1.4. Are these blades suitable for this turbine? Justify your answer with numerical evidence (a calculation). 2. A 2.1 MW wind turbine system has a rotor diameter of 78 m and a rated speed of 12 m/s. What is the efficiency of the entire wind turbine system? Assume a density of 1.225 kg/m3 .

Q.3 A rocket nozzle has a throat area of 18 cn? and combustion chamber pressure of 25 bars. If the specific impulse is 130 seco ids and weight flow rate is 44.145 N/s. Determine: (i) Thrust Coefficient (ii) Propellant Weight Flow Coefficien (iii) Specific Propellant Consumption a d (iv) Characteristic Velocity

Consider steam at 500 K and 200 kPa. Estimate its speed ofsound by two different methods: (a) assuming an ideal gasfrom Table B.4, or (b) using finite differences for isentropicdensities between 210 kPa and 190 kPa.

(1) A four-cylinder, two-stroke cycle diesel engine with 10.9 cm bore and 12.6 cm stroke produces 88 kW of brake power at 2000 r.p.m. compression ratio rc-18:1. calculate :- (a) engine displacement. (cm³,L) (b) brake mean effective pressure. (kpa) (c) torque. (N.m) (d) clearance volume of one cylinder. (cm³) ANS: (a) 4703,4.703, (b) 561, (c) 420, (d) 69.2

A turbine model has the following characteristics: Effective power: 13, 6 kW; Rotor Diameter: 0.38 meters, Flow: 0.34 ms, Energy Jump: 26.5 J / Kg and 3 R.P.S. rotation It is desired to construct a geometrically similar 1.20 meter diameter turbine that provides a power on the 656 kW axis, we ask: to calculate and justify its answers: a) the specific rotation; b) the unit quantities (rotation, flow and power); c) the rotation, flow and power of the model (bi-unit quantities).

What is the maximum power generated by the wind farm with wind speed of 4 m/s? Typical wind turbines have rotor diameters from 40 m to 90 m (Assume increment of 5 m for this problem)-40 m is 80% efficient and efficiency decreases by 5% for every 5 m increase in diameter (i.e. 45 m=75%, 50=70...)-The ridge is 10 km long and wind turbines will be spaced in a single row. •Power in the wind per unit area of circular area is 1/2ρv3W/m2 (v is the wind speed, ρ is 1.3 kg/m3 for air) •Wind turbines cannot be spaced closer than 5 times its diameter without loosing power also there are no partial turbines.

Water is flowing in a 5 cm diameter pipe at a velocity of 5 m/s. The pipe expands to a 10 cm diameter pipe. Calculate the pressure just after the expansion to a 10 cm diameter pipe if the prrssure in the 5 cm diameter pipe is 300 kPa. Friction is negligible. The specific weight of water is 9.81 kN/m³.A. 301.5 kPaB. 314.9 kPaC. 311.7 kPaD. 317.4 kPa

QUESTION 3 You are asked to select a new centrifugal pump for the piping system shown below that will be used to deliver 0.0233 m³/s of hot (50 °C) water from the storage tank into the reactor. The entire piping system is constructed from 10 cm internal diameter, wrought iron pipe. A gate valve is located between the pump outlet and reactor inlet. The storage tank and reactor are both closed vessels but they are vented to maintain atmospheric pressure above the liquid level. A local equipment supplier sends you the performance curves for four different pumps that are labelled 'Pump A', 'Pump B', 'Pump C', and 'Pump D'- the curves are shown on pages 7 & 8. Data: Water at 50 °C: Storage Tank density=988 kg/m³ viscosity = 0.000547 Pa's vapour pressure = 12.3 kPa 4 m ↓ 2 m ↑ L Reactor a. Calculate the available Net Positive Suction Head (NPSH). Note that previous experiments showed that the total head loss for the piping section between the storage tank and the pump, H has been determined…

show all working out please

Calculate the total thrust and aerodynamic power developed in a 3 blade wind turbine at a wind velocity of 9 m/s. The machine specifications are as follows:Diameter: 10 m; Rotational speed: 110 rpm; Blade length = 6 mTSR: 5.23; Chord Length: 0.55 m; Pitch angle: 5°Aerofoil section: NACA 23018; Distance from shaft to inner edge= 0.5 m