[L4]_WIND MEASUREMENT

Question 1

ENGY-688

What is the definition of wind speed?

[L4]

Answer 1

Wind speed is the air flow velocity in an atmosphere, affected by temperature and pressure.

[L4]

Question 2

ENGY-688

True or False: Wind behaves in a completely predictable manner due to its stochastic nature.

[L4]

Answer 2

False. Wind has a significant component of randomness.

[L4]

Question 3

ENGY-688

What are the two key planes in measuring wind velocity?

[L4]

Answer 3

Horizontal and vertical planes.

[L4]

Question 4

ENGY-688

What are the two major types of wind measurement configurations?

[L4]

Answer 4

In-situ measurements and remote sensing.

[L4]

Question 5

ENGY-688

What percentage of the chord length is the maximum thickness?

[L3]

Answer 5

30%

[L3]

Question 6

ENGY-688

Which of the following is NOT a method of remote sensing for wind measurements?
A) SODAR
B) LIDAR
C) Cup anemometer

[L4]

Answer 6

C) Cup anemometer.

[L4]

Question 7

ENGY-688

True or False: The inflow angle (α) affects the accuracy of wind speed measurements by causing an overestimation of the measured wind speed.

[L4]

Answer 7

True

[L4]

Question 8

ENGY-688

Anemometers are classified in terms of accuracy. What class represents the highest accuracy?

[L4]

Answer 8

Class 0.

[L4]

Question 9

ENGY-688

What is dynamic over-speeding?

[L4]

Answer 9

When a cup anemometer over-rotates in turbulent conditions, causing measurement errors.

[L4]

Question 10

ENGY-688

True or False: Tower shadow effects always increase the accuracy of wind measurements.

[L4]

Answer 10

False. They can cause a negative bias.

[L4]

Question 11

ENGY-688

What is the role of wind shear in wind measurements?

[L4]

Answer 11

Wind shear helps extrapolate wind speeds to different heights, allowing accurate predictions of wind behavior at various altitudes.

[L4]

Question 12

ENGY-688

What is the primary function of data loggers in wind measurement campaigns?

[L4]

Answer 12

To connect to sensors for gathering and transmitting data.

[L4]

Question 13

ENGY-688

What is the main purpose of a wind measurement campaign?

[L4]

Answer 13

To determine the best locations for wind turbines.

[L4]

Question 14

ENGY-688

How is turbulence intensity (TI) calculated?

[L4]

Answer 14

TI = σ / v̅, where σ is the standard deviation of wind speed and v̅ is the average wind speed.

[L4]

Question 15

ENGY-688

Which method has the advantage of measuring wind speed at heights higher than economically feasible by met-towers?

[L4]

Answer 15

Remote sensing methods (SODAR and LIDAR).

[L4]

Question 16

ENGY-688

True or False: Wind measurements should not be organized into bins for data analysis.

[L4]

Answer 16

False. Organizing into bins is important for analysis.

[L4]

Question 17

ENGY-688

What are the three types of validation checks performed on wind measurement data?

[L4]

Answer 17

Range test, relational test, trend test.

[L4]

Question 18

ENGY-688

How does the complexity of terrain affect the design of a wind measurement campaign?

[L4]

Answer 18

It determines the placement and number of met-towers needed for accurate data collection.

[L4]

Question 19

ENGY-688

What is the main advantage of using a met-tower over remote sensing for wind measurement?

[L4]

Answer 19

Met-towers provide reliable, bankable data at specific heights, whereas remote sensing measures wind over larger volumes and isn’t yet bankable.

[L4]

Question 20

ENGY-688

In the equations, what does the symbol δ represent?

[L4]

Answer 20

Tower shadow and boom effects can cause a negative bias of up to 1.5%. Mounting sensors on longer booms helps reduce this error.

[L4]