A web-based semi-empirical numerical tool for accessible liquid swirl injector design
- Paper ID
101978
- DOI
- author
- company
University of Bristol; King Mongkut's Institute of Technology Ladkrabang (KMITL)
- country
United Kingdom
- year
2025
- abstract
Swirl injectors are vital components to liquid rocket engine combustion intensification, offering high-performance propellant atomisation with relative ease of manufacture. However, despite their widespread use and utility, comprehensive, publicly available practical design methodologies remain scarce in the literature. To address this gap, this paper presents a web-based JavaScript tool employing an iterative semi-empirical numerical method for rapid first-order approximation design of general tangential inlet-type monopropellant and bipropellant liquid swirl injector geometries, based chiefly on the approach described by Bazarov {\it et al.} (2004). The tool calculates key geometric and flow parameters—including nozzle radius, radial inlet positions, spray cone angle, and Reynolds numbers—based on user-specified operating conditions such as pressure drop, fluid properties, and geometric coefficients. Special emphasis is given to the efficient implementation of the algorithm for rapid iteration. A CFD validation comparing the computed values against expected flow characteristics is ongoing, with initial results showing promising agreement in limited test cases. Analyses quantifying variances and defining valid regimes of sensible results are in-progress. Additionally, a structured design workflow is also proposed, addressing key limitations such as model prediction deviation due to insufficient air core formation in small injectors. This accessible computation tool aims to assist engineers and students in the predictable and iterative development of swirl injectors.