Vortex MCQs : Here you will find MCQ Questions related to "Vortex" in Aerodynamics. These Vortex MCQ Questions Will help you to improve your Aerodynamics knowledge and will prepare you for various Examinations like Competitive Exams, Placements, Interviews and other Entrance Exmaniations
Question 1
Vortices are a major component of?
A. Lifting Flow
B. Nonlifting Flow
C. Doublet Flow
D. Turbulent flow
View Answer
Ans : D
Explanation: Vortices are a major component of turbulent flow.
Question 2
In most vortices, the fluid flow velocity is greatest next to its axis and _________ in inverse proportion to the distance from the axis.
A. increases
B. decreases
C. same
D. All of the above
View Answer
Ans : B
Explanation: In most vortices, the fluid flow velocity is greatest next to its axis and decreases in inverse proportion to the distance from the axis.
Question 3
In the absence of external forces, a vortex usually evolves fairly quickly toward the irrotational flow pattern, where the flow velocity u is inversely proportional to the distance r. Irrotational vortices are also called?
A. Irrotational vortices
B. Rotational vortices
C. free vortices
D. stationary vortices
View Answer
Ans : C
Explanation: In the absence of external forces, a vortex usually evolves fairly quickly toward the irrotational flow pattern, where the flow velocity u is inversely proportional to the distance r. Irrotational vortices are also called free vortices.
Question 4
A surface that is everywhere tangent to both flow velocity and vorticity is called a?
A. steady tude
B. helmholtz tube
C. vortex tube
D. None of the above
View Answer
Ans : C
Explanation: A surface that is everywhere tangent to both flow velocity and vorticity is called a vortex tube. In general, vortex tubes are nested around the axis of rotation. The axis itself is one of the vortex lines, a limiting case of a vortex tube with zero diameter.
Question 5
The fluid motion in a vortex creates a dynamic pressure (in addition to any hydrostatic pressure) that is lowest in the core region.
A. TRUE
B. FALSE
C. Can be true or false
D. Can not say
View Answer
Ans : A
Explanation: The fluid motion in a vortex creates a dynamic pressure (in addition to any hydrostatic pressure) that is lowest in the core region, closest to the axis, and increases as one moves away from it, in accordance with Bernoulli's principle. One can say that it is the gradient of this pressure that forces the fluid to follow a curved path around the axis.
Question 6
Vortices need be steady-state features; they can not move and change shape.
A. TRUE
B. FALSE
C. Can be true or false
D. Can not say
View Answer
Ans : B
Explanation: Vortices need not be steady-state features; they can move and change shape.
Question 7
Vortices form in stirred fluids, and may be observed in?
A. smoke rings
B. whirlpools in the wake of a boat
C. dust devil
D. All of the above
View Answer
Ans : D
Explanation: Vortices form in stirred fluids, and may be observed in smoke rings, whirlpools in the wake of a boat, and the winds surrounding a tropical cyclone, tornado or dust devil.
Question 8
The free vortex flow forms _________
A. straight lines
B. hyperbola
C. parabola
D. concentric circles
View Answer
Ans : D
Explanation: The free vortex flow is a circulatory flow of the fluid such that its stream lines are concentric circles. The velocity components for a free vortex flow are Ur and Uθ and is equal to Ur=0 and Uθ=circulation/ 2*pi*r.
Question 9
Except at the origin where r=0, the vortex flow is ___________
A. rotational
B. laminar
C. irrotational
D. turbulent
View Answer
Ans : C
Explanation: Vortex flow is irrotational everywhere except at the point r=0, where the vorticity is infinite. Therefore, the origin, r=0, is a singular point in the flow field. Here, the origin point represents the singularity point.
Question 10
The strength of the vortex flow can be given by ______________
A. Γ=2*pi*C
B. Γ=2*pi
C. Γ=0
D. Γ=1
View Answer
Ans : B
Explanation: The circulation for vortex flow can be given by
Γ=2*pi*C where, C – constant and Γ is the strength of the vortex flow.
When Γ is positive, it means that vortex of positive strength rotates in the clockwise direction and vice versa.