沥青混合料铺筑温度场的有限差分仿真模型

为确定热态沥青混合料在特定条件下的铺筑温度场,建立了铺筑温度场的一维非稳态仿真模型。仿真模型采用有限差分隐式格式,取静态定值气温、风速、太阳辐射、表面洒水量、下承层初始温度场以及下承层材料热物性参数,每隔一时间步长而变化一次的表面传热系数、有效辐射、铺层材料导热系数和比热容,随前三次碾压每次非连续变化一次的铺层材料密度。从而将求解一维非稳态铺筑温度场转化为用数学工具求解沿铺层厚度方向任意位置处每隔一定时间间隔的温度值。结果表明:经仿真模型验证,确定了仿真模型的准确度和可信度。

Research on the Finite Difference Simulation Model of Asphalt Mixture Paving Temperature Field

In order to determine the asphalt mixture paving temperature field under certain conditions, the one-dimensional unsteady state simulation model of paving temperature field had been established. The simulation model had adopted the numerical solution of finite difference implicit format, using static values, air temperature, wind speed, solar radiation, sprinkler quantity, the initial temperature field of underlying materials and thermophysical parameters of underlying materials, selecting the surface heat transfer coefficient, effective radiation, thermal conductivity and specific heat capacity of paving materials, which varied with the time step, choosing densities of paving material per discontinuously changing during the first three times of compactions. Thus, the solution of one-dimensional unsteady paving temperature field had been transformed into solving temperature value of each time interval at any position along the thickness of the spreading layer with mathematical tool. Results show that the accuracy and dependability of the model have been confirmed.