How is velocity distributed across a circular tube during laminar flow__________________?
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Answer: C. varies parabolically with maximum at the centre
Explanation
Laminar velocity distribution inside circular tubes forms a mathematical paraboloid across the cross-section. Fluid velocity reaches its absolute maximum value at the centerline axis of the circular tube. No-slip boundary conditions ensure that the fluid velocity drops smoothly to zero at the walls. Viscous shear stresses dominate fluid motion during low Reynolds number laminar pipe flow regimes. Parabolic velocity profiles result from balancing pressure forces against viscous shear forces. Fluid particles travel fastest in the center where wall friction effects are weakest.
Mechanical engineers use this parabolic profile to analyze lubrication systems and microfluidic devices. Understanding velocity distribution prevents inaccurate flow rate estimations in medical infusion pumps. This foundational flow behavior underpins advanced analytical solutions in fluid mechanics. Constant velocity across the cross-section describes idealized slug flow rather than laminar pipe flow. Linear variation from walls to center describes simplified approximations rather than true parabolic profiles. Stating none of the above is incorrect because the parabolic description is universally accepted.
- Subject
- Engineering
- Category
- Civil Engineering
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- —
- Difficulty
- medium
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