The minimum fluidization velocity for a given particulate system is a function of___________________?
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Answer: D. All A., B. and C.
Explanation
Minimum fluidization velocity depends on drag forces balancing gravitational particle weights. Particle size and shape dictate the projected drag area and interstitial void spaces. Fluid density and viscosity determine the Reynolds number and viscous drag characteristics. Fluidization occurs when upward fluid drag equals the net weight of packed solid particles. The Ergun equation models pressure drop through packed beds using fluid and particle properties. Bed porosity increases as fluid velocity rises above the initial minimum fluidization point.
Petroleum refineries use fluidized catalytic cracking units requiring precise fluidization velocities. Industrial drying and gasification reactors depend on accurate minimum fluidization calculations. Designing solid-liquid contacting systems requires knowing the exact fluidization velocity thresholds. Option A ignores fluid properties such as density and viscosity that affect drag forces. Option B neglects particle characteristics like size, sphericity, and solid density entirely. Option C omits fluid viscosity, which is essential for calculating laminar friction drag.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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