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USING MATLAB The following system of equations is designed to determine concentr

ID: 3853778 • Letter: U

Question

USING MATLAB The following system of equations is designed to determine concentrations (x) in a series of coupled reactors as a function of the amount of mass input to each reactor (B) -- which is the right hand side of the system of equation ... A times x = B 15x1 -3x2 - x3 = 3800 -3x1 + 18x2 - 6x3 = 1200 -4x1 - x2 + 12x3 = 2350 a) Determine how much the rate of mass input to reactor 3 must be increased to induce a (30 g/m^3) rise in the concentration of reactor 1? Prove your solution is correct by finding x (using the solution technique of your choice) for both the original case and the modified reactor input -- then subtracting the values. The change for x1 should be 30.

Explanation / Answer

Please execute the below in Matlab command window.

Prepare the Matrix a as below:

>> a= [15 -3 -1;-3 18 -6;-4 -1 12];

>> b = [3800;1200;2350];

The solution to the matrix will give the solution here.

We will find x using the following method which uses inverse matrix method.

>> x = inv(a)*b

x =

320.2073

227.2021

321.5026

  

>> OriginalB = a * x

OriginalB =

1.0e+003 *

3.8000

1.2000

2.3500

Now lets change the concentration of reactor 1 to 30 and find the answer.

OriginalBPlus30 = a * [x(1)+30;x(2);x(3)]

OriginalBPlus30 =

1.0e+003 *

4.2500

1.1100

2.2300

Now to verify if our calculations are correct, we will first find x1 with OriginalBPlus30 as the new b.

>> x1 = inv(a)*OriginalBPlus30

x1 =

350.2073

227.2021

321.5026

We will subtract x from x1 to find the results are correct.

>> x1-x

ans =

30.0000

0.0000

0