中文摘要：

我们建议重写二个维的 Euler 方程的一个新方法并且基于夸张系统的典型理论导出一种原来的正规典型关系。这种关系沿着 bicharacteristic 方向，和罐头严格地包含衍生物在 1D 情况中被看作典型关系的 2D 延期。

英文摘要：

We propose a new way of rewriting the two dimensional Euler equations and derive an original canonical characteristic relation based on the characteristic theory of hyperbolic systems. This relation contains the derivatives strictly along the bicharacteristic directions, and can be viewed as the 2D extension of the characteristic relation in 1D case.