Head generation in a centrifugal pump is primarily governed by the____________________?
Show answer Hide answer
Answer: C. Angle of the vanes and the speed of the tip of the impeller
Explanation
Euler pump equation shows head generation depends directly on impeller speed and vane angles. Peripheral velocity at the impeller tip imparts kinetic energy to the pumped liquid. Blade exit angles dictate the vector resolution of tangential and radial velocity components. Centrifugal pumps convert mechanical driver energy into fluid pressure and velocity head. Impeller tip speed combines rotational speed and outer diameter into a single velocity term. Velocity triangles are graphical tools used by engineers to analyze blade angle performance.
Pump manufacturers design specific impeller geometries to meet target head and flow requirements. Selecting appropriate vane angles prevents flow separation and cavitation inside the pump casing. Variable speed drives utilize tip speed principles to adjust operational head across systems. Power represents the rate of energy transfer rather than the fundamental mechanism generating head. Nature of the liquid affects density and viscosity but does not dictate design head generation. Vapor pressure determines net suction head limits rather than operating impeller head development.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
Related questions
Q1. How is the lifting force of a balloon evaluated_________________?
Show answer Hide answer
Answer: B. Due to the weight of the atmospheric air, that it displaces
Archimedes principle establishes that buoyant force equals the weight of displaced atmospheric air. The surrounding gas exerts an upward pressure force that manifests as net lifting capacity. Displaced fluid weight deter...
Q2. Equal percentage valves relate flow rate ‘q’ to stem position ‘x’ through what mathematical equation_________________?
Show answer Hide answer
Answer: A. dq/dx = K
Equal percentage control valves are designed such that an incremental change in stem position produces a flow change proportional to the existing flow rate.
Q3. How does turbulent pipe friction head loss vary_________________?
Show answer Hide answer
Answer: C. Approximately as the square of the velocity
Turbulent friction head losses in smooth and rough pipes scale with velocity squared. Kinetic energy dissipation in turbulent eddies dominates the mechanical energy balance equations. Empirical friction factor correlatio...
Q4. Hypersonic flow of a compressible fluid corresponds to what range of Mach numbers____________________?
Show answer Hide answer
Answer: C. > 4
Hypersonic flow regimes are formally defined in fluid dynamics as exceeding Mach number 4. At these extreme speeds, high temperature gas dynamics and chemical dissociation become prominent. Shock wave angles become extre...
Q5. The center of pressure for a vertical rectangular surface of width ‘w’ submerged in static fluid is located at what depth (where y = liquid depth)?
Show answer Hide answer
Answer: B. 2y/3
Hydrostatic pressure on a vertical rectangle increases linearly with depth from the surface. Integrating pressure moments across the plate area places the center of pressure at two thirds depth. This point lies deeper th...
Q6. Head losses in open channel flow typically vary as a function of the ________________?
Show answer Hide answer
Answer: B. First power of the roughness
Open channel flow empirical formulas like Mannings equation incorporate roughness linearly. Frictional head losses vary directly with channel roughness coefficients in established equations. Higher surface roughness gene...