Aerosol Physics & Dynamics
Students investigate the physical behavior of airborne particles, from Brownian motion at the molecular level to fluid dynamics governing air flow in buildings, using mathematical models and computational simulations.
5
Lessons
5
Class Periods
Low
Materials Cost
3
NGSS Standards
Essential Question
How do the physical properties of particles and the fluid dynamics of air determine where aerosols travel, how long they remain suspended, and where they deposit?
Lessons
-
1→Brownian Motion and Diffusion
-
2→Particle Deposition Mechanisms
-
3→Fluid Dynamics of Air
-
4→Modeling Particle Behavior
-
5→Particle Physics Lab
Key Concepts
Brownian Motion
- D = kT/(6 pi eta r) (Stokes-Einstein)
- Random walk: x2 = 2Dt
- Dominates for d < 0.1 um
- Temperature dependence
Settling Velocity
- vs = (rhop - rhof)gd2/(18 eta)
- Stokes regime: Re < 1
- Dominates for d > 1 um
- Density and diameter dependence
Deposition Mechanisms
- Gravitational settling
- Inertial impaction
- Interception
- Diffusional deposition
Fluid Dynamics
- Re = rho v L / eta
- Laminar vs turbulent flow
- Boundary layers
- Particle-fluid coupling
Standards Alignment
| Standard | Description |
|---|---|
| HS-PS2-1 | Analyze data to support the claim that Newton's second law of motion describes the mathematical relationship among net force, mass, and acceleration |
| HS-PS2-6 | Communicate scientific and technical information about why the molecular-level structure determines macroscopic properties |
| HSF-IF.C.7 | Graph functions expressed symbolically and show key features of the graph |