Question

Linearized perturbation velocity potential equation is applicable for transonic flow.

(a) True

(b) False

The question was asked during an online exam.

Origin of the question is Linearized Velocity Potential Equation topic in chapter Linearized and Conical Flows of Aerodynamics

Answer 1

Right choice is (b) False

The explanation is: The linearized perturbation velocity potential is derived after taking making assumptions to convert the non – linear equation into linear equation. One of the assumption made is that for the flow between Mach number 0 and 0.8 (transonic flow), the term M\(_∞^2 \big [ \)(γ – 1) \(\frac {u^{‘}}{V_∞} + (\frac {γ + 1}{2}) \frac {u^{‘^2}}{V_{∞}^{2}} + (\frac {γ – 1}{2})(\frac {v^{‘{^2}} + w^{‘^{2}}}{V_∞^2}) \big ] \frac {∂u^{‘}}{∂x}\) in the non – linear perturbation velocity potential equation is ignored because of its negligible value. Due to this assumption, the linearized equation is not applicable for transonic flows.