$$\fracT_0 - T_\inftyT_i - T_\infty = \frac119 - 12125 - 121 = \frac-2-96 = 0.02083$$
$$0.02083 = [1.10 e^-(2.05)^2 Fo_cyl] \times [1.05 e^-(1.52)^2 Fo_slab]$$ But $Fo_cyl = \frac\alpha tR^2$, $Fo_slab = \frac\alpha tL^2 = Fo_cyl \times \fracR^2L^2 = Fo_cyl \times \frac0.04^20.06^2 = 0.444 Fo_cyl$ Introduction To Food Engineering Solutions Manual
$$Q = \dotm m c p,m (T_m,out - T_m,in)$$ $$Q = (0.5)(3900)(72 - 4) = 0.5 \times 3900 \times 68 = 132,600 \text W$$ $$\fracT_0 - T_\inftyT_i - T_\infty = \frac119 -
Let $X = Fo_cyl$: $$0.02083 = 1.155 \exp\left[-(4.2025)X - (2.3104)(0.444X)\right]$$ $$0.01803 = \exp\left[-(4.2025 + 1.025)X\right] = \exp(-5.2275 X)$$ out - T_m
For a short cylinder, use product solution: $$\fracT_0 - T_\inftyT_i - T_\infty = \left(\fracT_center,cyl - T_\inftyT_i - T_\infty\right) infinite\ cyl \times \left(\fracT center,slab - T_\inftyT_i - T_\infty\right)_infinite\ slab$$
Not required here.