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重力内波动力学中会出现浑沌(即确定性的非周期流),它是湍流的驱动因素和耗散因素相匹配的结果。Lorenz方程中,当Prandtl数σ=1时不出现浑沌是由于耗散因素太弱所致。浑沌的概念可以帮助解释大气湍流的发生。白天,不稳定的温度层结是湍流的驱动因素,分子粘性和某种速度切交是耗散因素。晚上,地面长波有效辐射等是湍流的驱动因素。引入速度切变阻尼以后,在真实的大气Prandtl数σ=0.7情况下,仍然可以出现浑沌。而且晚上Richardson数愈小愈易出现浑沌。这些都和基本观测事实相一致。
Chaos (ie, a deterministic aperiodic flow) occurs in the intragravity wave dynamics and is the result of a match between the driving and dissipating factors of turbulence. Lorenz equation, when Prandtl number σ = 1 does not appear chaos is due to the dissipation factor is too weak. The concept of chaos can help explain the atmospheric turbulence. During the day, unstable temperature stratification is the driving factor of turbulence, and molecular viscosity and some speed cutting are the dissipation factors. In the evening, long-wave effective radiation on the ground is the driving factor of turbulence. After the introduction of velocity-shear damping, chaos can still occur with a true Prandtl number of σ = 0.7. And the smaller the number of Richardson at night more prone to chaos. These are consistent with the basic observation facts.