For laminar flow of Newtonian fluids through a circular pipe, fluid velocity is proportional to (with μ = viscosity, and fixed pressure drop, length, and diameter)?
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Answer: B. 1/μ
Explanation
Hagen-Poiseuille law describes laminar Newtonian fluid flow through smooth circular pipes. Fluid velocity is inversely proportional to dynamic viscosity mu under fixed pressure drops. Higher fluid viscosity creates greater internal resistance, reducing overall flow velocity. Dynamic viscosity measures a fluid internal resistance to shear deformation forces. Newtonian fluids maintain constant viscosity regardless of applied shear rate magnitudes. Pressure drop and pipe geometry remain constant parameters in this specific relationship.
Lubrication oil systems must account for viscosity changes affecting flow velocities in bearings. Transporting heavy crude oils requires heating to reduce viscosity and increase flow speeds. Chemical processing of viscous polymer solutions relies on inverse viscosity flow scaling. Direct proportionality to viscosity would incorrectly suggest thicker fluids flow faster. Square root of viscosity is mathematically incorrect for Hagen-Poiseuille velocity profiles. Inverse square root notation incorrectly modifies the linear viscosity dependence.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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