BENG 221: Mathematical Methods in Bioengineering Lecture 12 Diffusion in Polar and Cylindrical Coordinates References Haberman APDE, Sec. 7.7, 7.8 and 7.9. http://en.wikipedia.org/wiki/Cylindrical_coordinate_system http://en.wikipedia.org/wiki/Bessel_function http://en.wikipedia.org/wiki/Fourier–Bessel_series n=0 1 0.8 0.6 0.4 J0((h0i)1/2l) 0.2 0 ï0.2 ï0.4 ï0.6 ï0.8 ï1 ï1 ï0.8 ï0.6 ï0.4 ï0.2 0 x (units R) 0.2 0.4 0.6 0.8 1 n=1 1 0.8 0.6 0.4 J1((h1i)1/2l) 0.2 0 ï0.2 ï0.4 ï0.6 ï0.8 ï1 ï1 ï0.8 ï0.6 ï0.4 ï0.2 0 x (units R) 0.2 0.4 0.6 0.8 1 n=2 1 0.8 0.6 0.4 J2((h2i)1/2l) 0.2 0 ï0.2 ï0.4 ï0.6 ï0.8 ï1 ï1 ï0.8 ï0.6 ï0.4 ï0.2 0 x (units R) 0.2 0.4 0.6 0.8 1 n=3 1 0.8 0.6 0.4 J3((h3i)1/2l) 0.2 0 ï0.2 ï0.4 ï0.6 ï0.8 ï1 ï1 ï0.8 ï0.6 ï0.4 ï0.2 0 x (units R) 0.2 0.4 0.6 0.8 1 n=4 1 0.8 0.6 0.4 J4((h4i)1/2l) 0.2 0 ï0.2 ï0.4 ï0.6 ï0.8 ï1 ï1 ï0.8 ï0.6 ï0.4 ï0.2 0 x (units R) 0.2 0.4 0.6 0.8 1 Cylindrical Value Boundary Conditions h01 = 5.783/R2 h02 = 30.47/R2 h03 = 74.89/R2 h04 = 139/R2 h05 = 222.9/R2 h11 = 14.68/R2 h12 = 49.22/R2 h13 = 103.5/R2 h14 = 177.5/R2 h15 = 271.3/R2 h21 = 26.37/R2 h22 = 70.85/R2 h23 = 135/R2 h24 = 218.9/R2 h25 = 322.6/R2 h31 = 40.71/R2 h32 = 95.28/R2 h33 = 169.4/R2 h34 = 263.2/R2 h35 = 376.7/R2 h41 = 57.58/R2 h42 = 122.4/R2 h43 = 206.6/R2 h44 = 310.3/R2 h45 = 433.8/R2 Cartesian Box Value Boundary Conditions h11 = 19.74/L2 h12 = 49.35/L2 h13 = 98.7/L2 h14 = 167.8/L2 h15 = 256.6/L2 h21 = 49.35/L2 h22 = 78.96/L2 h23 = 128.3/L2 h24 = 197.4/L2 h25 = 286.2/L2 h31 = 98.7/L2 h32 = 128.3/L2 h33 = 177.7/L2 h34 = 246.7/L2 h35 = 335.6/L2 h41 = 167.8/L2 h42 = 197.4/L2 h43 = 246.7/L2 h44 = 315.8/L2 h45 = 404.7/L2 h51 = 256.6/L2 h52 = 286.2/L2 h53 = 335.6/L2 h54 = 404.7/L2 h55 = 493.5/L2 n=0 1 0.8 0.6 0.4 J0((h0i)1/2l) 0.2 0 ï0.2 ï0.4 ï0.6 ï0.8 ï1 ï1 ï0.8 ï0.6 ï0.4 ï0.2 0 x (units R) 0.2 0.4 0.6 0.8 1 n=1 1 0.8 0.6 0.4 J1((h1i)1/2l) 0.2 0 ï0.2 ï0.4 ï0.6 ï0.8 ï1 ï1 ï0.8 ï0.6 ï0.4 ï0.2 0 x (units R) 0.2 0.4 0.6 0.8 1 n=2 1 0.8 0.6 0.4 J2((h2i)1/2l) 0.2 0 ï0.2 ï0.4 ï0.6 ï0.8 ï1 ï1 ï0.8 ï0.6 ï0.4 ï0.2 0 x (units R) 0.2 0.4 0.6 0.8 1 n=3 1 0.8 0.6 0.4 J3((h3i)1/2l) 0.2 0 ï0.2 ï0.4 ï0.6 ï0.8 ï1 ï1 ï0.8 ï0.6 ï0.4 ï0.2 0 x (units R) 0.2 0.4 0.6 0.8 1 n=4 1 0.8 0.6 0.4 J4((h4i)1/2l) 0.2 0 ï0.2 ï0.4 ï0.6 ï0.8 ï1 ï1 ï0.8 ï0.6 ï0.4 ï0.2 0 x (units R) 0.2 0.4 0.6 0.8 1 Cylindrical Flux Boundary Conditions h01 = 0/R2 h02 = 14.68/R2 h03 = 49.22/R2 h04 = 103.5/R2 h05 = 177.5/R2 h11 = 3.39/R2 h12 = 28.42/R2 h13 = 72.87/R2 h14 = 137/R2 h15 = 220.9/R2 h21 = 9.328/R2 h22 = 44.97/R2 h23 = 99.39/R2 h24 = 173.5/R2 h25 = 267.2/R2 h31 = 17.65/R2 h32 = 64.24/R2 h33 = 128.7/R2 h34 = 212.7/R2 h35 = 316.4/R2 h41 = 28.28/R2 h42 = 86.16/R2 h43 = 160.8/R2 h44 = 254.9/R2 h45 = 368.5/R2 Cartesian Box Flux Boundary Conditions h00 = 0/L2 h01 = 9.87/L2 h02 = 39.48/L2 h03 = 88.83/L2 h04 = 157.9/L2 h10 = 9.87/L2 h11 = 19.74/L2 h12 = 49.35/L2 h13 = 98.7/L2 h14 = 167.8/L2 h20 = 39.48/L2 h21 = 49.35/L2 h22 = 78.96/L2 h23 = 128.3/L2 h24 = 197.4/L2 h30 = 88.83/L2 h31 = 98.7/L2 h32 = 128.3/L2 h33 = 177.7/L2 h34 = 246.7/L2 h40 = 157.9/L2 h41 = 167.8/L2 h42 = 197.4/L2 h43 = 246.7/L2 h44 = 315.8/L2
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