一杯沸水冷却，圆柱体模型，底面半径0.05m，高0.1m，周围温度20度，初始水温100度

方程是四维输运方程（常数a^2=k/(c*p)，k是热传导系数0.6006焦/（米*秒*度））

初始条件：t=0时水等于100度

边界条件：1.上下壁都是自由冷却，第三类边界条件，周围温度保持在20度（H=k/h,h取1）

2.杯壁绝热，第二类边界条件

-cup of boiling water cooling cylinder model, the bottom radius of 0.05m, 0.1m high. temperature around 20 degrees, initial temperature of 100 degrees equation is four-dimensional equations (a constant ^ 2 = k / (c * p), k is the thermal conductivity coefficient of 0.6006 Coke / (m * * seconds degrees)) initial conditions : t = 0 to 100 degree water boundary conditions : 1. upper and lower walls are free cooling, the third boundary conditions, maintain the temperature around 20 degrees (H = k / h, h for 1) 2. Beibi insulation, the second boundary condition