Fluid flow behavior through a packed bed is modeled using the ______________ equation?
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Answer: B. Ergun’s
Explanation
Ergun equation is specifically formulated to predict pressure drop of fluid flowing through packed beds of particles. It combines viscous laminar energy losses and inertial turbulent losses into a single comprehensive mathematical model. This makes Ergun equation the universally accepted standard for packed bed reactor and filtration design. Packed beds consist of stationary columns filled with solid pellets, catalyst spheres, or Raschig rings. Fluid flowing through the tortuous void spaces between particles experiences severe directional changes and friction. Ergun equation integrates Carman-Kozeny laminar terms and Burke-Plummer turbulent terms into one unified expression.
Chemical reaction engineering relies on Ergun equation to calculate pressure drops across packed catalytic beds. Water purification plants use packed sand filter beds designed with Ergun pressure drop calculations. Optimizing bed void fraction and particle size prevents excessive blower power consumption in industrial packed towers. Fanning equation calculates pressure drop for empty circular pipes rather than tortuous packed particle beds. Hagen-Poiseuille equation applies strictly to straight laminar flow through smooth capillary tubes. Stating none of these are correct is false because Ergun equation was specifically created for packed beds.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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