7.2 An anemometer mounted 10 m above a surface with crops, hedges, and shrubs, shows a wind speed of 5 m/s. Assuming 15°C and 1 atm pressure, determine the following for a wind turbine with hub height 80 m and rotor diameter of 80 m: V top 80 m 120 m V bottom 80 m 21n A 40 m 5 m/s * 10 m Crops, shrubs, hedges FIGURE P7.2 a. Estimate the wind speed and the specific power in the wind (W/m²) at the highest point that the rotor blade reaches. Assume no air density change over these heights. b. Repeat (a) at the lowest point at which the blade falls. c. Compare the ratio of wind power at the two elevations using results of (a) and (b) and compare that with the ratio obtained using Equa- tion 7.20. d. What would the power density be at the highest tip of the blade if we include the impact of elevation on air density? Assume the temperature is still 15°C. Does air density change seem worth considering in the above analysis?

7.2 An anemometer mounted 10 m above a surface with crops, hedges, and shrubs, shows a wind speed of 5 m/s. Assuming 15°C and 1 atm pressure, determine the following for a wind turbine with hub height 80 m and rotor diameter of 80 m: V top 80 m 120 m V bottom 80 m 21n A 40 m 5 m/s * 10 m Crops, shrubs, hedges FIGURE P7.2 a. Estimate the wind speed and the specific power in the wind (W/m²) at the highest point that the rotor blade reaches. Assume no air density change over these heights. b. Repeat (a) at the lowest point at which the blade falls. c. Compare the ratio of wind power at the two elevations using results of (a) and (b) and compare that with the ratio obtained using Equa- tion 7.20. d. What would the power density be at the highest tip of the blade if we include the impact of elevation on air density? Assume the temperature is still 15°C. Does air density change seem worth considering in the above analysis?

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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