Which statements are true and which are false.
Consider the flow over the airfold. Look at the next statement:
With increasing Reynolds number:
1) the boundary layer thickness decreases while the transition location moves backwards.
2) the transition location moves forward shield drag increases.
3) the transition location moves forward shield drag decreases.
4) the boundary layer thickness decreases while the transition location moves forward.
To determine which statements are true and which are false, let's analyze each statement:
1) The boundary layer thickness decreases while the transition location moves backward.
- This statement is generally true. As the Reynolds number increases, the boundary layer tends to become thinner due to increased flow momentum, while the transition location moves toward earlier positions along the airfoil.
2) The transition location moves forward, shield drag increases.
- This statement is false. Generally, when the transition location moves forward (closer to the leading edge of the airfoil), it leads to an increase in drag. However, the specific term "shield drag" is not commonly used in aerodynamics.
3) The transition location moves forward, shield drag decreases.
- This statement is false. Similar to statement 2, a forward transition location does not typically result in a decrease in drag.
4) The boundary layer thickness decreases while the transition location moves forward.
- This statement is false. As mentioned in statement 1, the boundary layer thickness typically decreases with increasing Reynolds number, but the transition location moves backward, not forward.
Based on the analysis above, we can conclude that statement 1 is true, while statements 2, 3, and 4 are false.
1) True
2) False
3) False
4) False