Renormalized dissipation in the nonconservatively forced Burgers equation

Krommes, J.A.

Princeton University. Plasma Physics Laboratory.

关键词: Markov Process;    70 Plasma Physics And Fusion;    Plasma Simulation;    Scaling Laws;    Shear;   

DOI  :  10.2172/750289
RP-ID  :  PPPL--3422
RP-ID  :  AC02-76CH03073
RP-ID  :  750289

美国|英语

来源: UNT Digital Library

【 摘 要 】

A previous calculation of the renormalized dissipation in the nonconservatively forced one-dimensional Burgers equation, which encountered a catastrophic long-wavelength divergence approximately [k min]-3, is reconsidered. In the absence of velocity shear, analysis of the eddy-damped quasi-normal Markovian closure predicts only a benign logarithmic dependence on kmin. The original divergence is traced to an inconsistent resonance-broadening type of diffusive approximation, which fails in the present problem. Ballistic scaling of renormalized pulses is retained, but such scaling does not, by itself, imply a paradigm of self-organized criticality. An improved scaling formula for a model with velocity shear is also given.