HYMOR: An open-source package for global modal, non-modal, and receptivity analysis in high-enthalpy hypersonic vehicles

TL;DR

HYMOR is an open-source computational toolkit designed for comprehensive linear stability analysis of high-enthalpy hypersonic flows, including modal, non-modal, and receptivity analyses, with verified accuracy and real-gas modeling.

Contribution

It introduces a versatile, open-source framework with MATLAB and Julia implementations for advanced stability analysis of hypersonic flows, incorporating shock-fitting and real-gas effects.

Findings

Verified against benchmark cases demonstrating accuracy.

Capable of capturing complex interactions in hypersonic flow stability.

Includes models for real-gas thermochemistry.

Abstract

We present HYMOR (HYpersonic MOdal/non-modal, and Receptivity), an open-source computational framework for the linear stability analysis of high-enthalpy hypersonic flows. The toolkit includes MATLAB and Julia implementations and is released under the MIT license. HYMOR provides global modal, non-modal, and freestream receptivity analyses capable of capturing interactions among spatially separated physical mechanisms that are inaccessible to traditional local methods. A shock-fitting formulation is employed to treat the bow shock as a sharp discontinuity, ensuring that the interaction of infinitesimal disturbances with the shock reproduces the exact response predicted by linear interaction analysis. The code also solves the nonlinear equations for base-flow computation and automatically linearizes the resulting discrete operators for the stability analyses. Several thermochemical models are available for treatment of real-gas effects in high-enthalpy regimes. The numerical implementation is verified against a collection of benchmark cases that demonstrate the accuracy and capabilities of the toolkit across its modal, non-modal, and receptivity analysis modes.