Aerodynamics Multiple Choice Questions & Answers (MCQs) on “Three Dimensional Source”.
1. Is three dimensional source method is used for simulating incompressible potential flows?
a) True
b) False
Answer: a
Clarification: A three dimensional source method for simulating incompressible potential flows around a deforming body without the kutta condition. A three dimensional source vorticity method that does not use the kutta condition is proposed.
2. Is three dimensional incompressible potential flows around a body accompanied by a wake vortex?
a) False
b) True
Answer: b
Clarification: The three dimensional incompressible potential flows around a body accompanied by a wake vortex, surface singularity methods have been employed extensively owing to their ease of use and low solution times. In the case of vertical flow, the kutta condition is applied.
3. Is kutta condition is inapplicable in the case of blunt bodies?
a) False
b) True
Answer: a
Clarification: The kutta condition is inapplicable in the case of blunt bodies. For this reason, a three dimensional source –vorticity method for simulating incompressible potential flows around a deforming body without using the kutta condition.
4. Is kutta condition is applicable to the lifting cases?
a) True
b) False
Answer: b
Clarification: The lifting or vertical cases where the kutta condition cannot be applicable, a rotating sphere in uniform flow and a sphere with a vortex ring are considered. To assess the accuracy of the proposed method, the numerical results compared with the analytical solution.
5. Is potential and current sources are defined at each node?
a) True
b) False
Answer: a
Clarification: potential and current source are defined at each node. In the three dimensional, each interior node is connected to the six surrounding nodes by impedance branches. Potentials and current sources are defines at each successive nodes.
6. Is impedance is calculated from resistivity?
a) True
b) False
Answer: a
Clarification: The impedances are calculated from resistivity values given at the node locations and the distances between the nodes. This is analogous to a network of resistors, were current flows through the branches and the potential are defined at all intersections.
7. Is three dimensional aerodynamic are considering irrotational, inviscid flow?
a) True
b) False
Answer: a
Clarification: Three dimensional aerodynamics by considering the simple case of irrotational, inviscid flow. When compressibility can also be neglected, we consider a solution to Laplace’s equation in three dimensional just as in the two dimensional case.
8. Is source is used in three dimensional?
a) True
b) False
Answer: a
Clarification: In two dimensional we used sources and vortices extensively to construct the flow over an airfoil. In three dimensional we also use sources and vortices to model the flow over the wings and the bodies. This section shows how this is done.
9. Is velocity potential is obtained by solving a set of simultaneous equations?
a) True
b) False
Answer: a
Clarification: The velocity potential is obtained by solving a set of simultaneous equations. These added masses are calculated by giving acceleration to the body or the fluid, which helps to solve velocity potential in a set of simultaneous equation.
10. Is wake vortex will produce around the three dimensional flow?
a) True
b) False
Answer: a
Clarification: The three dimensional incompressible potential flows around a body accompanied by a wake vortex, surface singularity method have been employed extensively, owing to their ease of use and low solution times.
