Definition of streamline (laminar) flow The flow in which each fluid particle follows a definite path and the paths of adjacent particles do not intersect is called:
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Astream line flow
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Buniform flow
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Csteady flow
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Dturbulent flow
Answer
Correct Answer: stream line flow
Explanation
Introduction / Context:Fluid motions are categorized to analyze stability, mixing, and energy losses. A key distinction is between orderly, layered motion and random, fluctuating motion. The former is described by streamlines that never cross.
Given Data / Assumptions:
- Inviscid or viscous fluids may both exhibit streamline (laminar) behavior at sufficiently low Reynolds numbers.
- Paths are conceptual curves tangent to the velocity vector at every point.
Concept / Approach:Streamline (laminar) flow is characterized by smooth, parallel layers; each particle follows a fixed path, and neighboring paths do not intersect. This differs from “steady flow” (no time variation at a point) and “uniform flow” (no spatial variation along a reach). Turbulent flow has random fluctuations and eddies.
Step-by-Step Solution:
Identify the defining phrase “definite path” and “paths do not cross”.These are the hallmark features of streamline/laminar flow.Thus, choose “stream line flow”.Verification / Alternative check:In dye-streak experiments at low Re, a thin colored filament stays coherent—indicating streamlines that do not intersect.
Why Other Options Are Wrong:
- Uniform flow: property constancy along space, not about particle paths crossing.
- Steady flow: time invariance at a fixed point; streamlines can still be complex.
- Turbulent flow: inherently involves fluctuating, intermingling paths.
Common Pitfalls:Equating “steady” with “laminar”—they are independent attributes; a steady flow can be turbulent.
Final Answer:stream line flow