PROBLEM 1 A spherical, cryosurgical probe may be imbedded in diseased tissue for the purpose of freezing, and
thereby destroying the tissue. Consider a probe of 3 diameter whose surface is maintained at
−30 ℃ when imbedded in tissue that is at 37 ℃. A spherical layer of frozen tissue forms around the
probe, with a temperature of 0 ℃ existing at the interface between the frozen and normal tissue. If
the thermal conductivity of frozen tissue is approximately 1.5 /(.) and heat transfer at the
interface may be characterized by an effective convection coefficient of 50 /2
., what is the
thickness of the layer of frozen tissue? Assume negligible perfusion