Under constant pressure drop and steady laminar conditions, fluid velocity varies as the cube of cylindrical pipe diameter for ____________ fluid.
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Answer: B. Pseudo-plastic
Explanation
Pseudo-plastic fluids exhibit shear-thinning non-Newtonian behavior under external stress. Mathematical derivation of steady laminar flow for pseudo-plastic fluids reveals a cubic dependence on diameter. This higher-order relationship distinguishes pseudo-plastic velocity profiles from standard Newtonian pipe flows. Non-Newtonian fluids have viscosities that change depending on the applied shear rate or stress. Pseudo-plastic materials become less viscous as they are stirred, pumped, or forced through pipes. Power-law models are commonly used to describe the flow curves of these specialized industrial fluids.
Pulp suspensions, paints, and certain polymer solutions behave as pseudo-plastic fluids during processing. Designing transport systems for shear-thinning materials requires specialized non-Newtonian friction formulas. Understanding velocity dependence helps prevent clogging and excessive pressure buildup in chemical plants. Option A describes Newtonian fluids, which follow a quadratic Hagen-Poiseuille velocity dependence. Option C refers to dilatant fluids, which exhibit shear-thickening behavior and square-root velocity trends. Option D represents Bingham plastics, which require a yield stress before movement initiates.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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