The actual velocity at the vena contracta for fluid discharging from a reservoir through an orifice is expressed as_________________?
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Answer: B. C.V. √(2gh)
Explanation
Actual velocity accounts for energy losses through a specialized velocity coefficient term. Theoretical velocity is given by the Torricelli square root of two g h expression. Multiplying theoretical velocity by the velocity coefficient yields actual vena contracta velocity. Vena contracta is the jet cross-section where fluid streamlines become completely parallel. Frictional losses inside orifices reduce fluid velocity below theoretical frictionless values. Velocity coefficient is the ratio of actual velocity to ideal theoretical velocity.
Tank draining calculations require actual velocity coefficients to predict accurate discharge times. Hydraulic engineering applications use discharge coefficients combining velocity and contraction effects. Orifice meter calibrations rely on empirical coefficients to match real fluid behavior. Sqrt(2gh) represents the theoretical ideal velocity without accounting for any frictional losses. Cd times sqrt(2gh) incorporates the overall discharge coefficient instead of velocity coefficient. Cc times sqrt(2gh) uses the contraction coefficient instead of the velocity coefficient term.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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