{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

# 04-05 - Expected results C For a conservative material C =...

This preview shows pages 1–4. Sign up to view the full content.

Upstream , J = u/E and C = C O e JX , AND X is negative, so C decreases exponentially. Upstream, J is positive but X is negative so Expected results X=0 C For a conservative material C = C O downstream i.e , J= (1-1) = 0 2 u E For a non conservative material, k 0, and J will be negative downstream , so C decreases exponentially. Upstream , J is positive but X is negative so C still decreases exponentially. Note that the magnitude of C O is smaller (for the same Q W and C W )when k 0.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Example (an old CEE 351 Exam problem) A sewage outfall is to be located downstream from a bathing area. If the waste and river characteristics are as specified below, how far downstream must the outfall be if 200 MPN/100 mL (coliform conc.) is allowable at the beach?
Given: Q river = 10 10 L/dy u = 40,000 m/dy (constant) E = 10 7 m 2 /dy Q waste = 10 7 L/day C waste = 10 8 MPN coliforms 100 mL coliform die off may be modeled with first order kinetics i.e., dC = - kC dt and k = 0.1/day u = 40,000 m/dy beach Q = 10 10 L/dy continuous input Desire C = 200 MPN/100mL at this point.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern