Explore topic-wise MCQs in Computational Fluid Dynamics.

This section includes 10 Mcqs, each offering curated multiple-choice questions to sharpen your Computational Fluid Dynamics knowledge and support exam preparation. Choose a topic below to get started.

1.

Which type of grids is the best for flow over an airfoil?

A. Stretched grids
B. Adaptive grids
C. Boundary-fitted grids
D. Elliptic grids
Answer» D. Elliptic grids
2.

What are zonal grids?

A. Grids generated for a particular zone of the domain of interest
B. Grids varying at different zones
C. Grids generated for a particular time in the flow
D. Grids varying with time
Answer» B. Grids varying at different zones
3.

What does elliptic grid generation mean?

A. Grids generated for elliptic equations
B. Grids transformed with elliptic equations
C. The computational domain is elliptic
D. The object under consideration is elliptic
Answer» C. The computational domain is elliptic
4.

Which of these properties are balanced by using adaptive grids?

A. Accuracy and convergence
B. Efficiency and stability
C. Accuracy and stability
D. Accuracy and efficiency
Answer» E.
5.

Let x, y be the coordinates in the physical domain and ξ, η be the coordinates in the computational domain. Which of these is correct for adaptive grids?

A. \(\frac{\partial\xi}{\partial x}≠1 \)
B. \(\frac{\partial\xi}{\partial x}≠0 \)
C. \(\frac{\partial\xi}{\partial t}≠0 \)
D. \(\frac{\partial\xi}{\partial t}≠1 \)
Answer» D. \(\frac{\partial\xi}{\partial t}≠1 \)
6.

Adaptive grids change automatically based on ______________

A. flow field gradients
B. time rate of change of the flow properties
C. grid gradients
D. time rate of change of the grid points
Answer» B. time rate of change of the flow properties
7.

Consider a divergent nozzle as shown in the figure. Let x, y be the coordinates in the physical domain and ξ, η be the coordinates in the computational domain. Which of these equations can give the best-suited grid for this system?

A. ξ=x; η = y×ys
B. ξ=x×ys; η=y×ys
C. \(\xi=\frac{x}{y_s};\eta=\frac{y}{y_s}\)
D. \(\xi=x;\eta=\frac{y}{y_s}\)
Answer» E.
8.

Form the continuity equation for steady 2-dimensional flow when the x-direction grids are stretched.Density → ρx and y-velocities → u,vCoordinates in physical domain → x,yCoordinates in computational domain → ξ, η.

A. \(e^\eta\frac{\partial(\rho u)}{\partial\xi}+\frac{\partial(\rho v)}{\partial\eta}\)
B. \(\frac{\partial(\rho u)}{\partial\xi}+e^\xi\frac{\partial(\rho v)}{\partial\eta}\)
C. \(\frac{\partial(\rho u)}{\partial\xi}+e^\eta\frac{\partial(\rho v)}{\partial\eta}\)
D. \(e^\xi\frac{\partial(\rho u)}{\partial\xi}+\frac{\partial(\rho v)}{\partial\eta}\)
Answer» C. \(\frac{\partial(\rho u)}{\partial\xi}+e^\eta\frac{\partial(\rho v)}{\partial\eta}\)
9.

Let x, y be the coordinates in the physical domain and ξ, η be the coordinates in the computational domain. In which of these cases, the horizontal lines are stretched and the vertical lines are equally spaced?

A. ξ=x; η=ln⁡(y+1)
B. ξ=ln⁡(x+1); η=y
C. ξ=x; η=y
D. ξ=ln⁡(x+1); η=ln⁡(y+1)
Answer» B. ξ=ln⁡(x+1); η=y
10.

Which of these analyses needs a stretched grid?

A. Transient flow over a flat plate
B. Incompressible flow over a flat plate
C. Viscous flow over a flat plate
D. Subsonic flow over a flat plate
Answer» D. Subsonic flow over a flat plate