Hi everybody... i would like to seek help for the problem below. the assumptions i've considered is that transfer is radial only since it is a very long cylinder (infinitely long) that transfer in z direction is negligible, thermal radiation is zero, and wood properties are constant. Starting from the general energy equation i've come with a form similar to a modified bessel function of zero order but I'm stuck after that. i hope you may be able to help me. thanks a lot in advance. Problem : Burning of a wooden dowel In a fire research experiment, a long wooden dowel ( around rod), diameter 1.00 inch, temperature 74°F, is placed in a stream of 1,500°F air. The heat transfer coefficient between gas and surface is 5 Btu/h-ft2-F. Estimate the exposure time up to ignition of the rod on the assumption that ignition takes place when the surface temperature reaches 750°F. Wood Properties at 74°F Ρ= 50 lb/ft3 k = 0.10 Btu/h-ft-F cp = 0.6 Btu/lb-F assume that the wood properties are constant up to 750°F. Neglect the possible role of thermal radiation.