We extend two known dynamical systems obtained by Blaszak, et al. via choosing Casimir functions and utilizing Novikov-Lax equation so that a series of novel dynamical systems including generalized Burgers dynamical s...We extend two known dynamical systems obtained by Blaszak, et al. via choosing Casimir functions and utilizing Novikov-Lax equation so that a series of novel dynamical systems including generalized Burgers dynamical system, heat equation, and so on, are followed to be generated. Then we expand some differential operators presented in the paper to deduce two types of expanding dynamical models. By taking the generalized Burgers dynamical system as an example, we deform its expanding model to get a half-expanding system, whose recurrence operator is derived from Lax representation, and its Hamiltonian structure is also obtained by adopting a new way. Finally, we expand the generalized Burgers dynamical system to the (29-1)-dimensional case whose Hamiltonian structure is derived by Poisson tensor and gradient of the Casimir function. Besides, a kind of (29-1)-dimensional expanding dynamical model of the (29-1)-dimensionaJ dynamical system is generated as well.展开更多
We investigate initial-boundary-value problem for three-dimensional magnetohydrodynamic (MHD) system of compressible viscous heat-conductive flows and the three-dimensional full compressible Navier-Stokes equations....We investigate initial-boundary-value problem for three-dimensional magnetohydrodynamic (MHD) system of compressible viscous heat-conductive flows and the three-dimensional full compressible Navier-Stokes equations. We establish a blowup criterion only in terms of the derivative of velocity field, similar to the Beale^Kato-Majda type criterion for compressible viscous barotropic flows by Huang et al. (2011). The results indicate that the nature of the blowup for compressible MHD models of viscous media is similar to the barotropic compressible Navier-Stokes equations and does not depend on further sophistication of the MHD model, in particular, it is independent of the temperature and magnetic field. It also reveals that the deformation tensor of the velocity field plays a more dominant role than the electromagnetic field and the temperature in regularity theory. Especially, the similar results also hold for compressible viscous heat-conductive Navier-Stokes flows, which extend the results established by Fan et al. (2010), and I-Iuang and Li (2009). In addition, the viscous coefficients are only restricted by the physical conditions in this paper.展开更多
基金Supported by the Fundamental Research Funds for the Central University under Grant No.2017XKZD11
文摘We extend two known dynamical systems obtained by Blaszak, et al. via choosing Casimir functions and utilizing Novikov-Lax equation so that a series of novel dynamical systems including generalized Burgers dynamical system, heat equation, and so on, are followed to be generated. Then we expand some differential operators presented in the paper to deduce two types of expanding dynamical models. By taking the generalized Burgers dynamical system as an example, we deform its expanding model to get a half-expanding system, whose recurrence operator is derived from Lax representation, and its Hamiltonian structure is also obtained by adopting a new way. Finally, we expand the generalized Burgers dynamical system to the (29-1)-dimensional case whose Hamiltonian structure is derived by Poisson tensor and gradient of the Casimir function. Besides, a kind of (29-1)-dimensional expanding dynamical model of the (29-1)-dimensionaJ dynamical system is generated as well.
基金supported by National Natural Science Foundation of China(Grant Nos.11171236 and 71372189)Program for Changjiang Scholars and Innovative Research Team in University(Grant No.IRT1273)+1 种基金Sichuan Youth Science and Technology Foundation(Grant No.2014JQ0003)China Postdoctoral Science Foundation(Grant No.2013M542285)
文摘We investigate initial-boundary-value problem for three-dimensional magnetohydrodynamic (MHD) system of compressible viscous heat-conductive flows and the three-dimensional full compressible Navier-Stokes equations. We establish a blowup criterion only in terms of the derivative of velocity field, similar to the Beale^Kato-Majda type criterion for compressible viscous barotropic flows by Huang et al. (2011). The results indicate that the nature of the blowup for compressible MHD models of viscous media is similar to the barotropic compressible Navier-Stokes equations and does not depend on further sophistication of the MHD model, in particular, it is independent of the temperature and magnetic field. It also reveals that the deformation tensor of the velocity field plays a more dominant role than the electromagnetic field and the temperature in regularity theory. Especially, the similar results also hold for compressible viscous heat-conductive Navier-Stokes flows, which extend the results established by Fan et al. (2010), and I-Iuang and Li (2009). In addition, the viscous coefficients are only restricted by the physical conditions in this paper.