Assignment on Wind Turbine Design and Analysis

Submission Guidelines

All assignments must be submitted by the date and time specified above.

Students are required to submit an electronic copy of their completed assignment via the Assignments section of Canvas and follow any specific instructions. Any change to this instruction will be advised via Canvas.

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Discuss environmentally related technologies and materials that are fundamental in a range of industries including construction, structural mechanics, automotive and environmental operations.

Discuss environmental issues related to resource provision and consumption  necessary for the manufacture of engineered products, and analyse potential for the application of alternative energy sources.

Specify and develop energy efficient and environmentally conscious products.

The aim of this assignment is to extend your ability to apply analytical techniques to the design and performance of wind turbines.

This assignment is for a group of two students. Only ONE report should be submitted to CANVAS with font size of Arial 11 point and appropriate margins and 1 line spacing. Layout Format: Academic style. References Style Harvard and Vancouver. There is no maximum number of images and diagrams. Use equation editor in Microsoft Word for writing the equations in your assignment.

Wind Turbine Technology and Application

In this section there are SIX problems related to wind turbine you need to attempt all.

Question 1

Under these conditions

(i) What is the rotational speed of the rotor when it operates at tip speed ratio of 5.0? and how much is the tip speed?

(ii) If the generator needs to turn at 1800 rpm, what gear ratio is needed to match the rotor speed to the generator speed?

(iii) What is the overall efficiency of the complete wind turbine (blades, gear box and generator) under these conditions?

Question 2

Draw a power output versus wind speed diagram for a typical industrial wind turbine and label all important parameters on the graph. Explain what are

(i) Cut-in speed,

(ii) Rated wind speed,

(iii) Cut-out (Furling) wind speed.

Question 3

There are three major losses in the rotor of wind turbines. These include Profile losses, Tip losses, and Swirl losses. Discuss each of these losses in details.

Question 4

Design an optimum blade based on Betz and Schmitz for a three-b

(a) Give formulas for calculating the chord length and the pitch angle of the blade based on optimum Betz and Schmitz methods. Note that the pitch angle is defined as the angle between the chord line and the plane of blade rotation. Assume a pitch angle of zero.

Explain all symbols and quantities that appear in the formulas and draw a figure explaining the angles.

(b) Define the design point parameters

(c) Apply the formulas to a three-bladed turbine for blades with radius R = 40m and a pitch angle of zero: explain how you select the values of the parameters appearing in the formulas, and fill in the Table below, with r being the distance from the hub along the blade in meter.

(d) Plot variation of c/R and twist angle versus r/R.

(e) Explain why the blades have to be twisted.

Question 5

A three bladed wind turbine has a rotor diameter of 10 m. The performance

measurements according to the wind speed are given in the table below:

1. a) The turbine manufacturer displays a rated power of 8 kW for 9 m/s. Is this a valid rated power for this turbine?
2. b) How much is the performance coefficient of the wind turbine at 9 m/s. Assume the density of air ρ = 1.225 kg/m3
3. c) The annual operating time is defined as the ratio of the energy bought back during a year (365 days) of operation of the installation by the maximum active powerfor the same installation (9 kW). Calculate the annual operating time of this wind turbine.

d) The investment cost of this wind turbine is £32500. Operation and maintenance costs (O&M) are estimated at £550 / year. In order to evaluate the return on investment and given electricity purchase price as defined below, calculate the payback time (PBT) of the installation (i.e. time for which the income from the wind turbine covers its cost).