Revise equations (10-58) to (10-60) to allow two inter- linked columns of the type shown in Figure

Question:

Revise equations (10-58) to (10-60) to allow two inter- linked columns of the type shown in Figure to be solved simultaneously by the NR method. Does the matrix equation that results from the Newton'Raphson procedure still have a block tridiagonalstructure?

Mij =lij(1+ 8;)+ vi, j(1+S;)– li, j-1 – vi, j+l – fi.j =0 (10-58)