86-1 The Basic Concept of Temperature Field And Heat Conduction 1. The temperature field The total of the temperature at all the points in a 0 Unstable temperature filed or nonsteady temperature field: The temperature clastic body at a certain moment, denoted by t in the temperature field changes with time i.e. T-T(x, y, 2, t) Stable temperature filed or steady temperature field The temperature in the temperature field is only the function of positional coordinates i.e. TT(x,y, Plane temperature field: The temperature in temperature field only changes ith two positional coordinates i.e. T=T O x,y,t) 77 §6-1 The Basic Concept of Temperature Field And Heat Conduction 1.The temperature field: The total of the temperature at all the points in a elastic body at a certain moment, denoted by T. Unstable temperature filed or nonsteady temperature field: The temperature in the temperature field changes with time. i.e. T=T（x，y，z，t） Stable temperature filed or steady temperature field: The temperature in the temperature field is only the function of positional coordinates. i.e. T=T（x，y，z） Plane temperature field: The temperature in temperature field only changes with two positional coordinates. i.e. T=T（x，y，t）