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GATE 2026 AE – Question 19

Aerodynamics · Two-dimensional potential flow: sources, sinks, doublets, point vortex and Bernoulli's equation · 1 mark · Multiple choice

The velocity potential function ($\varphi$) given below represents which one of the following?

$\varphi = 5x - 12y$

  1. Doublet
  2. Irrotational vortex
  3. Source
  4. Uniform flow

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Show answer and explanation

Correct answer: (D) Uniform flow

Explanation

The velocity components are $u = \frac{\partial \varphi}{\partial x} = 5$ and $v = \frac{\partial \varphi}{\partial y} = -12$, both constant, so the flow is a uniform stream of speed 13.