Thermal–structural response and life prediction of lattice regenerative cooling thrust chambers in liquid rocket engines based on a simplified viscoplastic model

Abstract

With advances in aerospace technology, the reusability of liquid rocket engines has become the focus of considerable research interest. Traditional channel-type regenerative cooling thrust chambers often experience plastic deformation and microcracks, which limit their lifespan. This study proposed a novel lattice regenerative cooling thrust chamber using a simplified viscoplastic model and ABAQUS finite element software to simulate thermal–structural responses under different pressure conditions. The lattice structure not only enhanced the cooling efficiency and reduced the structural weight but also mitigated the plastic deformation and high-temperature creep of the inner wall. At an inner-wall temperature of 820 K, creep damage was significant. Compared to that of traditional chambers, the lattice structure of the proposed chamber exhibited different mechanical behavior and failure modes, with a more uniform stress distribution and initial failure occurring at the lattice nodes. The proposed design avoided the “doghouse” effect evident in traditional chambers, achieving an inner-wall lifespan of up to 202 cycles, a 359 % improvement. The high design flexibility of the lattice structure in the cooling channels enabled enhanced thrust chamber longevity. The study results provide new insights and technical support for next-generation liquid rocket engine designs.