科学准确地模拟分析森林火灾蔓延动态对防灾减灾救灾工作具有重要意义。现有的林火蔓延模拟方法在林火蔓延计算和可视化表达上,耦合程度低且难以将动态物理模型计算结果实时可视化表达。针对这一问题,本文在综合考虑国内外各种火灾蔓延...科学准确地模拟分析森林火灾蔓延动态对防灾减灾救灾工作具有重要意义。现有的林火蔓延模拟方法在林火蔓延计算和可视化表达上,耦合程度低且难以将动态物理模型计算结果实时可视化表达。针对这一问题,本文在综合考虑国内外各种火灾蔓延模型优缺点的基础上,选取应用广泛的Rothermel模型作为物理模型。通过惠更斯理论优化了火灾演进范围边界点割裂的不足,采取着火点密度阈值控制种子点数量与模拟可视化效率的平衡;利用布尔运算提高多着火点蔓延范围计算效率,将火灾模型与Open Scene Graph的粒子系统进行紧密耦合,完成火灾演进可视化表达。本文方法实现了对森林火灾蔓延的精确计算和实时、逼真模拟,为灾害应急部门提供信息化支撑。展开更多
In this paper, we establish a mathematical model of the forest fire spread process based on a partial differential equation. We describe the distribution of time field and velocity field in the whole two-dimensional s...In this paper, we establish a mathematical model of the forest fire spread process based on a partial differential equation. We describe the distribution of time field and velocity field in the whole two-dimensional space by vector field theory. And we obtain a continuous algorithm to predict the dynamic behavior of forest fire spread in a short time. We use the algorithm to interpolate the fire boundary by cubic non-uniform rational B-spline closed curve. The fire boundary curve at any time can be simulated by solving the Eikonal equation. The model is tested in theory and in practice. The results show that the model has good accuracy and stability, and it’s compatible with most of the existing models, such as the elliptic model and the cellular automata model.展开更多
文摘科学准确地模拟分析森林火灾蔓延动态对防灾减灾救灾工作具有重要意义。现有的林火蔓延模拟方法在林火蔓延计算和可视化表达上,耦合程度低且难以将动态物理模型计算结果实时可视化表达。针对这一问题,本文在综合考虑国内外各种火灾蔓延模型优缺点的基础上,选取应用广泛的Rothermel模型作为物理模型。通过惠更斯理论优化了火灾演进范围边界点割裂的不足,采取着火点密度阈值控制种子点数量与模拟可视化效率的平衡;利用布尔运算提高多着火点蔓延范围计算效率,将火灾模型与Open Scene Graph的粒子系统进行紧密耦合,完成火灾演进可视化表达。本文方法实现了对森林火灾蔓延的精确计算和实时、逼真模拟,为灾害应急部门提供信息化支撑。
文摘In this paper, we establish a mathematical model of the forest fire spread process based on a partial differential equation. We describe the distribution of time field and velocity field in the whole two-dimensional space by vector field theory. And we obtain a continuous algorithm to predict the dynamic behavior of forest fire spread in a short time. We use the algorithm to interpolate the fire boundary by cubic non-uniform rational B-spline closed curve. The fire boundary curve at any time can be simulated by solving the Eikonal equation. The model is tested in theory and in practice. The results show that the model has good accuracy and stability, and it’s compatible with most of the existing models, such as the elliptic model and the cellular automata model.
