MCQOPTIONS
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MCQOPTIONS
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. |
The Spalart-Allmaras model is best suited for ___________ |
| A. | turbulent jet flows |
| B. | turbulent mixing layers |
| C. | turbulent boundary layers with slight pressure gradients |
| D. | turbulent boundary layers with adverse pressure gradients |
| Answer» E. | |
| 2. |
The rate of dissipation of kinematic eddy viscosity parameter is Cw1ρ\((\frac{\tilde{ν}}{κy})^2 f_w\). What is the length scale used here? |
| A. | κy |
| B. | (κy)2 |
| C. | \(\frac{C_{w1}}{y}\) |
| D. | \(\frac{y}{C_{w1}} \) |
| Answer» B. (κy)2 | |
| 3. |
The rate of production of the kinematic eddy viscosity parameter is related to ___________ |
| A. | rate of dissipation of kinetic energy |
| B. | turbulence frequency |
| C. | vorticity |
| D. | kinetic energy |
| Answer» D. kinetic energy | |
| 4. |
Expand the Reynolds stress term \(-\rho \overline{u_{i}^{‘} u_{j}^{‘}}\) for the Spalart-Allmaras model. |
| A. | \(-\rho \overline{u_{i}^{‘} u_{j}^{‘}} = \rho \overline{v} f_{v1} (\frac{\partial U_i}{\partial x_i}+\frac{\partial U_j}{\partial x_j})\) |
| B. | \(-\rho \overline{u_{i}^{‘} u_{j}^{‘}} = \rho \overline{v} f_{v1} (\frac{\partial U_i}{\partial x_j}+\frac{\partial U_j}{\partial x_i})\) |
| C. | \(-\rho \overline{u_{i}^{‘} u_{j}^{‘}} = 2\rho \overline{v} f_{v1} (\frac{\partial U_i}{\partial x_i}+\frac{\partial U_j}{\partial x_j})\) |
| D. | \(-\rho \overline{u_{i}^{‘} u_{j}^{‘}} = 2\rho \overline{v} f_{v1} (\frac{\partial U_i}{\partial x_j}+\frac{\partial U_j}{\partial x_i}) \) |
| Answer» C. \(-\rho \overline{u_{i}^{‘} u_{j}^{‘}} = 2\rho \overline{v} f_{v1} (\frac{\partial U_i}{\partial x_i}+\frac{\partial U_j}{\partial x_j})\) | |
| 5. |
Near the wall, the first wall damping function tends to ___________ |
| A. | -1 |
| B. | 1 |
| C. | 0 |
| D. | ∞ |
| Answer» D. ∞ | |
| 6. |
At high Reynolds numbers, the first wall damping function becomes ___________ |
| A. | -1 |
| B. | 1 |
| C. | 0 |
| D. | ∞ |
| Answer» C. 0 | |
| 7. |
The first wall damping function in the Spalart-Allmaras model is a function of ___________ |
| A. | the product of the dynamic eddy viscosity parameter and the dynamic eddy viscosity |
| B. | the ratio of the dynamic eddy viscosity parameter and the dynamic eddy viscosity |
| C. | the product of the kinematic eddy viscosity parameter and the kinematic eddy viscosity |
| D. | the ratio of the kinematic eddy viscosity parameter and the kinematic eddy viscosity |
| Answer» E. | |
| 8. |
In the Spalart-Allmaras model, the dynamic eddy viscosity in terms of the kinematic eddy viscosity parameter (v) is given by __________ (Note: fν1 is the wall damping function and ρ is the density of flow). |
| A. | ρvfν1 |
| B. | (ρv) ⁄ fν1 |
| C. | (ρfν1) ⁄ v |
| D. | v ⁄ (ρfν1) |
| Answer» B. (ρv) ⁄ fν1 | |
| 9. |
The transport equation in the Spalart-Allmaras model is for the transport of ___________ |
| A. | kinematic eddy viscosity parameter |
| B. | kinematic eddy viscosity |
| C. | dynamic eddy viscosity parameter |
| D. | dynamic eddy viscosity |
| Answer» B. kinematic eddy viscosity | |
| 10. |
The Spalart-Allmaras model differs from the RANS equations by ___________ |
| A. | four extra transport equations |
| B. | one extra transport equation |
| C. | two extra transport equations |
| D. | three extra transport equations |
| Answer» C. two extra transport equations | |