Determination of the thermo-physical properties of multi-layered biological tissues

•The thermal-wave model of bio-heat transfer in multi-layered biological tissues is investigated.•The thermo-physical properties of multi-layer biological tissues are identified.•The numerical investigation revealed sufficient conditions for the unique recovery of the unknowns.•Numerical results show accurate and stable recovery of the unknown physical properties of interest. Abnormal biological tissues possess unknown properties that must be estimated in order to decide the appropriate method of treatment in terms of amount of dosage and appropriate place of inoculation. The current work numerically investigates, for the first time, the simultaneous estimation of several thermo-physical properties of multi-layered tissues from internal temperature measurements. The heat propagation within the tissues is modelled by the thermal-wave model of bio-heat transfer, accounting for the finite speed of heat propagation. On the skin surface, a convective boundary condition holds taking into account the heat exchange with the environment, whilst on the most inner wall of the tissues a Dirichlet boundary temperature condition is prescribed. Accurate and stable reconstruction of the piecewise constant properties given by the thermal conductivity, heat capacity and blood perfusion rate is successfully achieved for two physical examples concerning three- and four-layered, one-dimensional tissues, subjected to externally induced aggression.