Engineering Questions with Answers - Multiple Choice Questions
Aerodynamics – Nonlifting Flow over Arbitrary Bodies
1 - Question
Purpose of non-lifting flow over an arbitrary body is _____________
a) to find a numerical method
b) to find a mathematical method
c) to find a lifting body
d) to find a drag body
View Answer
Explanation: The purpose of non-lifting flow over an arbitrary bodies is to find a numerical method for appropriate solution on a high speed digital computer. The technique is called the source panel. The numerical solution of potential flows by both source and vortex panel techniques has revolutionized the analyses of low speed flows.
2 - Question
The combination of elementary flows is to synthesize the flow over this specified body?
a) False
b) True
View Answer
Explanation: The shape of an arbitrary body depends on the distribution of singularities which in combination with a uniform stream, produce the flow over the given body.T he purpose of this elementary flow is to present such a direct method, limited for the present to non-lifting flows.
3 - Question
Is source panel method became the standard aerodynamic tool in industry?
a) False
b) True
View Answer
Explanation: The numerical method for an appropriate solution on high speed digital computer. This technique is called source panel method, which, since the late 1960’s, has become a standard aerodynamic tool in industry and most research laboratories.
4 - Question
Is numerical solution of source and vortex panel techniques has revolutionized the analysis of low speed flows?
a) True
b) False
View Answer
Explanation: The numerical solution of potential flows by both source and vortex panel techniques has revolutionized the analysis of low-speed flows. The purpose of the numerical solution is to introduce the basic ideas of the source panel method, which is a technique for the numerical solution of non-lifting flows over arbitrary body.
5 - Question
Is small section of the source sheet can be treated as a distinct source of strength?
a) False
b) True
View Answer
Explanation: The strength of an infinitesimal portion of the sheet. This is small section of the source sheet can be treated as a distinct source of strength. The flow is located at a distance from dx. The carterian coordinates of ‘P’ are (x, y). This is the small section of the source sheet of strength xds induces an infinitesimally small potential.
6 - Question
Is complete velocity potential at point ‘p’ is obtained by entire source sheet from a to b?
a) True
b) False
View Answer
Explanation: By integrating from a to b the complete velocity potential is obtained at point p and it can change from position to negative along the sheet, that is the source sheet is really a combination of line source and line sinks.
7 - Question
Is arbitrary shape body can use in free stream velocity?
a) True
b) False
View Answer
Explanation: Source sheet is used to cover the surface of the arbitrary body were the strength varies in such a fashion that the combined action of the uniform flow and the source sheet makes the airfoil surface as stream line of the flow.
8 - Question
Why source strength ‘X’ per unit length is constant over a given panel?
a) It allows it to varies from one panel to next panel
b) It does not allow it to varies from one panel to next panel
c) It remains in the same panel
d) The length will be changes from panel to panel
View Answer
Explanation: The source strength ‘X’ per unit length be constant over a given panel but allow it to vary from one panel to the next, that if there are total n panel. The source panel strength per unit length is ‘Xn’. Therefore boundary condition is imposed numerically by defining the midpoint of each panel.
9 - Question
Is boundary condition is applied at the control point?
a) False
b) True
View Answer
Explanation: The boundary condition is applied at the control point that is the normal component of the flow velocity is zero at the control points. This component of freestream velocity is perpendicular to the panel and ‘n’ be the unit volume to the ith panel directed out of the body.
10 - Question
Is vector (v) is positive when directed away from the body?
a) True
b) False
View Answer
Explanation: The direction of the outward unit normal vector is positive when directed away from the body and it is carried out in the denominator at a singular point arises on the ith panel because the control point itself can be the contribution to the j=1 panel.
11 - Question
What is the normal component of the flow velocity at the rth control point?
a) Sum of the freestream
b) Sum of source line
c) Sum of the sink line
d) Sum of the source and sink line
View Answer
Explanation: The normal component of the flow velocity at the rth control point is the sum of that due to the free stream and that due to the source panels. The boundary condition stats that this sum must be zero and it is the cruse of the source panel method.