IVENS DANIEL HOFFMANN; JAN MARTIN; WOLFGANG ARMBRUSTER; DMITRY SUSLOV; JAN DEEKEN; JUSTIN HARDI
DOI Number: 10.13009/EUCASS2023-031
For the performance and stability of liquid propellant rocket engines, injector behavior is of utmost importance. A major problem is achieving an effective chemical reaction and a highly efficient homogeneous mixture of fuels with a minimum chamber length. These processes are also crucial in many other modern combustion systems such as chemical industrial plants, heating systems, and engines, which lead to extremely high requirements for the injection equipment. This article presents a concept for an injection system based on the application of different porous materials and oxidizer injectors. The system has been designed based on DLR Lampoldshausen’s heritage within porous injection technologies and its possible future use at the DLR LUMEN Technology Demonstrator. The setup has been successfully implemented and operated under sub-to-supercritical pressure conditions (tested from 35 to 65 bar), with respect to the critical pressure of oxygen, using the penta-injector research combustor. Optical investigations of the nearinjector combustion and flow field behavior for different penta-injector elements were conducted. Fuel was injected through a metallic mesh (Rigimesh®) or sinter bronze (CA-100). As for the oxygen injector, three different variations were tested: a conventional axial injector, a pentagon pattern riffling injector, and a helical swirl injector. The latter two were manufactured using Additive Layering Manufacturing (ALM).