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takbq2
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1. Suppose that three tanks in series, connected by pipes of the same size are filled with water that is moved through the system with pumps at the rate of 5 gal/min. The first tank is 1000 gal. The second tank is 750 gal. And the third tank is 500 gal. The contents of each tank is vigorously stirred. The in-feed to Tank 1 is a constant flow of water in the same sized pipe from an external source at the same flow rate and the outflow from Tank 3 flows into a lake at the same flow rate. [Dye is added to the inflow at a constant rate for exactly one minute per hour over a long period of time (weeks, months,whatever)]
What is the concentration of the dye RELATIVE to its input concentration as a function of time over a 10-hour period after the "long-time" has passed.
Do you have to make further assumptions to solve the problem?
How do you deal with the "relative" concentration?
2. Okay so obviously this is a conservation of mass problem, so flow in - flow out = 0
3. I have drawn an accurate picture, and I have set up what I believe to be the correct system of equations:
x1' = (QsA - Q12x1)*1/V1
x2' = (Q12x1 - Q23x2)*1/V2
x3' = (Q23x2 - Q3Lx3)*1/V3
Where:
x1 = Concentration in Tank 1, so on for x2 and x3
A = Entrance rate of substance with units kg*t/v
Q1 = rate at which the substance is transported by water flow (same throughout)
V1 = Volume of tank 1, so on for V2, V3.
Whatever you guys know what this stuff means these are straight forward normally but this one is throwing me off bad. I don't know if my system is right or what to solve I've been working on it and the rest of a huge problem set for too long.
It is due tomorrow morning. Please help.
What is the concentration of the dye RELATIVE to its input concentration as a function of time over a 10-hour period after the "long-time" has passed.
Do you have to make further assumptions to solve the problem?
How do you deal with the "relative" concentration?
2. Okay so obviously this is a conservation of mass problem, so flow in - flow out = 0
3. I have drawn an accurate picture, and I have set up what I believe to be the correct system of equations:
x1' = (QsA - Q12x1)*1/V1
x2' = (Q12x1 - Q23x2)*1/V2
x3' = (Q23x2 - Q3Lx3)*1/V3
Where:
x1 = Concentration in Tank 1, so on for x2 and x3
A = Entrance rate of substance with units kg*t/v
Q1 = rate at which the substance is transported by water flow (same throughout)
V1 = Volume of tank 1, so on for V2, V3.
Whatever you guys know what this stuff means these are straight forward normally but this one is throwing me off bad. I don't know if my system is right or what to solve I've been working on it and the rest of a huge problem set for too long.
It is due tomorrow morning. Please help.