Fluid Flow and Viscosity

What are the factors that affect fluid flow?

What is the main reason for the transition from laminar to turbulent flow?

What is viscosity a measure of?

What happens to the viscosity of a liquid as its temperature decreases?

What is the assumption in describing fluid motion based on the continuity equation?

What is constant in a narrowing pipe according to the continuity equation?

What remains constant when the fluid flows through a narrowing pipe?

What is the relationship between the speed of a fluid and its pressure according to Bernoulli's principle?

Why does the fluid flow faster when it passes through a narrower pipe?

What is the application of Bernoulli's principle in aircraft and helicopters?

What happens to the pressure of the fluid when its velocity increases?

Fluid Flow Factors

Fluid flow depends on the characteristics of the fluid, including viscosity and compressibility, as well as the speed of flow and the shape of the solid surface.

Laminar and Turbulent Flow

Laminar flow becomes turbulent when differences in velocity between successive layers of fluid create variations in pressure and density.

Viscosity

Viscosity is a measure of a fluid's resistance to flow and is caused by internal friction from the fluid's molecules moving against each other.
Hot liquids have lower viscosities than cold liquids, and therefore flow faster.
As temperature decreases, liquid molecules interact more, increasing viscosity.

Fluid Motion Assumptions

Assumptions for describing fluid motion include: incompressible (density does not change), laminar flow (flows perfectly smooth), and no viscosity.

Continuity Equation

The mass of fluid passing through any given area of the pipe does not change over time – mass flow rate is constant.
Continuity equation: mass flow rate and fluid velocity are related.

Bernoulli's Principle

Bernoulli's principle states that the pressure of a fluid decreases as the speed of the fluid increases.
High-speed flow is associated with low pressure, and low-speed flow is associated with high pressure.
Bernoulli's principle allows wings to produce lift and planes and helicopters to fly.

Explore the factors affecting fluid flow, including viscosity, compressibility, and surface shape. Learn about the transition from laminar to turbulent flow and the role of internal friction in viscosity.