2.3. Advection

Try these first

1. 1.

   Define advection in your own words.

   Hint

   Think about how rivers move water and anything in it.

2. 2.

   Explain how molecular diffusion differs from advection.

   Hint

   Consider what drives each process.

3. 3.

   What is advection?

   • The process of diffusion
   • Movement of fluid carrying substances
   • A type of pollution

   Hint

   Think about how fluids carry objects downstream.

4. 4.

   True or False: Diffusion is always the dominant process in moving pollutants in flowing water.

   • True
   • False

   Hint

   Consider the speed of flowing rivers versus still waters.

5. 5.

   A chemical spill occurs in a river where flow velocity is measured at 2 m/s. If diffusion coefficient for the pollutant in water is 1 x 10^-5 m^2/s, calculate the effective transport mechanism when both processes co-exist.

   Hint

   Compare coefficients of both processes.

6. 6.

   You are tasked with modeling the pollutant transport in a groundwater system. How does the porosity of the soil impact both advection and diffusion?

   Hint

   Consider how fluid can move through water-saturated systems.