A Vibration Analysis of Redesigned Starship Propellant Feedlines using One-way Fluid-Structure Interaction

Seoyeon Lee; Seungwhan Baek

doi:10.6108/KSPE.2026.30.3.070

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2026 Vol.30, Issue 3 Preview Page

A Vibration Analysis of Redesigned Starship Propellant Feedlines using One-way Fluid-Structure Interaction 단방향 유체-구조 상호작용을 적용한 재설계된 Starship 추진제 이송 배관의 진동 해석

30 June 2026. pp. 70-80

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Abstract

SpaceX implemented structural reinforcements and revised propellant feedline configurations in the Starship V2 to improve reusability. While initial V2 test flights reported structural failure and propellant leakage due to intense propulsion system vibrations, the platform later achieved full mission success. This research provides a vibration engineering analysis of the unpredictable dynamic phenomena stemming from the geometric discrepancies between V1 and V2 feedlines. By developing a one way fluid-structure interaction model that accounts for operational load and hydrostatic pressure conditions at the point of failure, this study qualitatively evaluates the dynamic responses through frequency response analysis.

Keywords

One-way Fluid-Structure Interaction

Vibration Analysis

Propellant Feedline

SpaceX는 Starship 재사용을 위해 V1에서 V2로 구조 안정성을 증대 보강하였고 추진제 이송 배관 형상을 변경했다. 이때 V2를 적용한 Starship 기체는 초기 시험비행에서 추진계통에서 강한 진동으로 인한 하드웨어 손상과 연료 누출이 보고되었고, 이후 시험비행에서는 전주기 임무를 달성한다. 본 연구는 Starship V1과 V2의 배관 형상 차이가 추진계통의 동적 거동에 예측 불가능한 현상을 일으킨 원인을 진동공학적으로 분석한다. 문제가 발생한 시점의 하중 조건과 유체의 압력 조건을 포함한 단방향 유체-구조 상호작용 모델을 구성하고 주파수응답해석을 통해 동특성을 정성적으로 비교 제시한다.

키워드

단방향 유체-구조 상호작용

진동 해석

추진제 이송 배관

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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 :3
Pages :70-80
Received Date : 2026-03-12
Revised Date : 2026-05-12
Accepted Date : 2026-05-25
DOI :https://doi.org/10.6108/KSPE.2026.30.3.070

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

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