Design and Verification of a Depressurization System for Liquid Nitrogen Densification for Liquid Oxygen Subcooling

Janghwan Lee; Yongwook Kim; Youngsung Ko

doi:10.6108/KSPE.2026.30.4.054

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2026 Vol.30, Issue 4 Preview Page Next Page

RESEARCH PAPERS

Design and Verification of a Depressurization System for Liquid Nitrogen Densification for Liquid Oxygen Subcooling 액체산소 과냉각을 위한 액체질소 고밀도화 감압시스템 설계 및 검증

31 August 2026. pp. 54-63

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Abstract

Applying propellant densification can increase the amount of propellant loaded into a launch vehicle's tank, thereby enhancing its performance. This study designed and constructed a depressurization system using a vacuum pump to densify cryogenic fluid, liquid nitrogen, and verified its performance through testing. Experiments to verify liquid nitrogen densification were conducted and categorized based on the circulation of liquid oxygen. In the heat exchanger-only test, liquid nitrogen densification was achieved up to 66 K, and in the liquid oxygen circulation test, liquid nitrogen reached 70 K, confirming that it met the requirements of the depressurization system.

Keywords

LN2

Subcooled

Densification

Vacuum Pump

추진제 고밀도화를 적용하여 발사체 탱크에 더 많은 추진제를 탑재하여 발사체의 성능을 향상시킬 수 있다. 본 연구는 극저온 유체인 액체질소를 고밀도화하기 위해 진공펌프를 사용한 감압시스템을 설계 및 구축하였고, 시험을 통해 검증하였다. 액체질소 고밀도화 검증을 위한 시험을 액체산소의 순환 여부에 따라 구분하여 수행하였으며, 열교환기 단독시험에서 66 K까지 액체질소의 고밀도화를 수행하였고, 액체산소 순환시험에서 액체질소가 70 K까지 도달하여 감압시스템의 요구조건에 부합하는 것을 검증하였다.

키워드

액체질소

과냉각

고밀도화

진공펌프

References

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Information

Publisher :The Korean Society of Propulsion Engineers
Publisher(Ko) :한국추진공학회
Journal Title :Journal of the Korean Society of Propulsion Engineers
Journal Title(Ko) :한국추진공학회지
Volume : 30
No :4
Pages :54-63
Received Date : 2026-05-08
Revised Date : 2026-06-23
Accepted Date : 2026-06-28
DOI :https://doi.org/10.6108/KSPE.2026.30.4.054

Journal of the Korean Society of Propulsion Engineers ISSN:1226-6027(Print) 2288-4548(Online) 한국추진공학회지

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