Fluid Flow Basics: 18 flashcards
All 18 flashcards from this kit, free and with no sign-up.
1. What is the definition of a fluid?
Show the answer
A substance that deforms continuously under an applied shear stress, no matter how small.
2. State Newton's law of viscosity.
Show the answer
Shear stress is proportional to the velocity gradient: $\tau = \mu \frac{du}{dy}$.
3. What is the difference between Newtonian and non-Newtonian fluids?
Show the answer
Newtonian fluids have constant viscosity regardless of shear rate; non-Newtonian fluids have viscosity that changes with shear rate.
4. Define volumetric flow rate and mass flow rate.
Show the answer
Volumetric flow rate $Q = A \cdot v$ (m³/s); mass flow rate $\dot{m} = \rho \cdot Q$ (kg/s).
5. What is the continuity equation for steady incompressible flow?
Show the answer
$A_1 v_1 = A_2 v_2$ or $Q_1 = Q_2$.
6. What does Bernoulli's equation represent and what are its assumptions?
Show the answer
It represents energy conservation along a streamline: $P + \frac{1}{2}\rho v^2 + \rho g h = \text{constant}$. Assumptions: inviscid, steady, incompressible flow along a streamline.
7. What is the Reynolds number and its physical significance?
Show the answer
$Re = \frac{\rho v D}{\mu}$. It indicates whether flow is laminar (Re < 2100) or turbulent (Re > 4000) in a pipe.
8. Define laminar flow and turbulent flow.
Show the answer
Laminar flow: smooth, parallel layers with no mixing; turbulent flow: chaotic, with eddies and mixing.
9. What is the Darcy-Weisbach equation for head loss due to friction in a pipe?
Show the answer
$h_f = f \frac{L}{D} \frac{v^2}{2g}$.
10. What is the friction factor in laminar flow?
Show the answer
$f = \frac{64}{Re}$.
11. What is the hydraulic diameter for a non-circular duct?
Show the answer
$D_h = \frac{4A}{P}$, where A is cross-sectional area and P is wetted perimeter.
12. What is the principle of a Venturi meter?
Show the answer
It measures flow rate by creating a pressure drop via a constriction; using Bernoulli's equation and continuity.
13. What is cavitation in fluid flow?
Show the answer
Formation and collapse of vapor bubbles when local pressure falls below vapor pressure, potentially causing damage.
14. What is the purpose of a pump in a fluid flow system?
Show the answer
To add energy to the fluid, increasing its pressure or head to overcome friction and elevation changes.
15. Define the term 'head' in fluid flow.
Show the answer
Head is the height of a fluid column that represents a specific energy per unit weight (e.g., pressure head, velocity head, elevation head).
16. What is the difference between a pump and a compressor?
Show the answer
A pump handles liquids (incompressible), while a compressor handles gases (compressible) and significantly increases pressure.
17. What is the function of a control valve in a flow system?
Show the answer
To regulate flow rate or pressure by varying the size of the flow passage.
18. What is the NPSH (Net Positive Suction Head) requirement for a pump?
Show the answer
It is the minimum suction pressure required to prevent cavitation at the pump inlet.
Your notes can be a kit like these
Every kit here was made from real study material. Point Veda at a chapter, a PDF, a photo or a link and get notes, flashcards, practice MCQs, games and a scored test — free, in 42 languages.
- Chapter notes
- Flashcards
- Practice MCQs
- Scored tests
- Exam prep
Get Veda free See what students get
Free to start · No ads · Works in 42 languages