Chemical Engineering - MCQ Practice Questions

A sharp-crested weir has a crest length of 2.0 m. If the head over weir is 0.4 m, calculate the discharge using Francis formula. (Use C_d = 0.623)

The Blasius equation for friction factor in turbulent flow is valid for:

Water flows through a pipe at 15°C (ρ = 999 kg/m³, μ = 1.139×10⁻³ Pa·s). If flow rate is 0.05 m³/s through a 0.1 m diameter pipe, is the flow laminar or turbulent?

In open channel flow, the Froude number (Fr) determines the type of flow. For a rectangular channel with depth 0.5 m and velocity 1.5 m/s, calculate the Froude number (g = 9.81 m/s²).

For turbulent flow in smooth pipes, which equation is commonly used to estimate friction factor?

The minor losses in pipe fittings are expressed as K×(V²/2g) where K is the loss coefficient. For a 90° elbow with Re = 50,000, typical K value is:

In a centrifugal pump, the head developed is given by Euler's pump equation. If impeller outlet tangential velocity is 20 m/s and inlet tangential velocity is 4 m/s, calculate theoretical head (g = 9.81 m/s²):

In boundary layer theory on a flat plate, the displacement thickness δ* represents:

For compressible flow through a nozzle, if pressure drops significantly and reaches sonic conditions, the Mach number at that point is:

A hydraulic jump occurs in open channel flow when:

The Moody diagram is used to determine friction factor for pipe flow. It shows that friction factor increases with:

For a horizontal pipe with diameter variation from D₁ to D₂, if pressure difference is ΔP and ignoring losses, the velocity ratio V₁/V₂ is: