Numerical Study on Liquid-Fuel Atomization Characteristics of a Honeycomb-Corrugated Vaporizer Tube for a Micro-Turbine Engine

Efficient liquid-fuel combustion in micro-combustors strongly depends on fuel atomization, evaporation, and fuel-air mixture preparation. However, conventional straight vaporizer tubes often provide limited droplet breakup and insufficient gas liquid heat and mass transfer. In this study, a honeycomb-corrugated vaporizer tube was proposed to enhance fuel atomization and evaporation before combustion. A computational fluid dynamics model combined with an orthogonal design was employed to investigate the effects of corrugation height, corrugation radius, honeycomb-hole diameter, and number of honeycomb plates on gas–liquid two-phase flow, the Sauter mean diameter (SMD), and fuel evaporation rate. The results showed that corrugation height and the number of honeycomb plates were the dominant factors affecting atomization and evaporation performance. The optimized tube, with a corrugation height of 1.0 mm, a corrugation radius of 4.0 mm, three honeycomb plates, and a honeycomb-hole diameter of 0.6 mm, reduced the outlet SMD from 79.0 μm to 42.6 μm and increased the fuel evaporation rate from 1.5% to 42.0%. These findings provide a feasible structural approach for improving fuel atomization, evaporation, and mixture preparation in small-scale liquid-fuel combustors.