Nonlinear quantum photonics serves as a cornerstone in the realm of photonic quantum technologies including photonic quantum compusing and quantum communication. The emergence of silicon pho- tonics platform not only offers the advantage of large-scale manufacturing but also provides a variety of engineering controls. To fully harness the potential of this platform, a comprehensive simulation framework is essential. Such a framework should be capable of accommodating features like adiabatic waveguide, material anisotropy, and linear optics. In this context, we introduce a simulation framework designed to accurately simulate these critical aspects. Furthermore, utilizing this framework, we have developed a novel device. This design integrates a cascaded nonlinear component with temporal walk-off compensation, exhibiting several advantageous features. Notably, it demonstrates the ability to enhance the squeezing parameter without the need for increased input energy.