formally covariant perturbation

例句：

1. 1. The formally covariantperturbation model is widely usedin the field of fluid dynamics.
   正式协变扰动模型在流体动力学领域得到了广泛应用。
2. 2. In this study, we investigated theformally covariant perturbationof a nonlinear system.
   在这项研究中，我们研究了一个非线性系统的正式协变扰动。
3. 3. The formally covariant perturbation method has been proven to beeffective in solving complex engineering problems.
   正式协变扰动方法已被证明在解决复杂工程问题方面是有效的。