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GATE 2026 BT – Question 47

Fundamentals of Biological Engineering · Bioreaction Engineering: Batch, fed-batch and continuous processes, microbial and enzyme reactors, optimization and scale up · 2 marks · Multiple select

For a liquid flowing in a circular cross section pipe, the transition from laminar to turbulent flow will NOT depend on which of the following factor(s)?

  1. The diameter of the pipe
  2. The length of the pipe
  3. The linear velocity of the liquid
  4. The viscosity of the liquid

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Show answer and explanation

Correct answer: (B) The length of the pipe

Explanation

The transition depends on the Reynolds number $Re = \frac{\rho vD}{\mu}$, which contains the diameter, the velocity and the viscosity but not the length of the pipe.