Abstract

The DLR LUMEN (Liquid Upper stage deMonstrator ENgine) rocket engine comprises of two separate turbopumps, one each for Liquid Oxygen (LOX) and Liquified Natural Gas (LNG) supply. In both turbopumps, an identical bearing block separates the pump section from the turbine section. In the current design, the bearing block features an oil-jet lubrication system to cool and lubricate the bearings during operation. Cryogenic conditions at the pump-interface and high temperature conditions at turbine-interface impose thermal constraints on the selection of a suitable lubricant for the bearing assembly and the design of the lubrication system.As a starting point to address this challenge, this paper presents a preliminary uncoupled finite element thermal model of the LUMEN LOX turbopump. The thermal model investigates the thermal behavior of the housing and rotor components in the bearing housing from start-up to shutdown of the turbopump. The model employs thermal worst case conditions to establish the operational thermal envelope of the turbopump system. Spatial and temporal evolution of the temperature at critical points within the bearing housing are reported.The model, albeit the uncertainties rooted from its empirical nature, provides beneficial insight into the thermal characteristics of the turbopump assembly. This serves as a first estimate of the thermal constraints for the selection of lubricant oil.

Highlights

  • Introduction and backgroundTurbopumps are high speed rotary fluid machines used in rocket engines

  • As a starting point to address this challenge, this paper presents a preliminary uncoupled finite element thermal model of the LUMEN Liquid Oxygen (LOX) turbopump

  • A worst case approach is adopted to identify the extreme conditions the lubricant oil is expected to encounter in the bearing cavity

Read more

Summary

Introduction

Turbopumps are high speed rotary fluid machines used in rocket engines. Their main purpose is to intake propellants from the tanks and deliver them at a higher pressure to the combustion chamber using suitable plumbing. The bearings in the DLR LUMEN (Liquid Upper stage deMonstrator ENgine) turbopumps are planned to be oil cooled and lubricated. This unconventional choice of the conventional lubrication system is attributed to the modular design approach followed in the LUMEN project [2]. The cryogenic conditions at the pump and the high temperature conditions at the turbine introduce thermal constraints on the lubricant oil. If the oil reaches a temperature lower than it’s pour

Results
Discussion
Conclusion
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.