Fluids Engineer

Responsibilities

• Define and analyse the overall propellant management architecture, including propellant location, acquisition strategy, residuals, and depletion behaviour
• Analyse microgravity and low-acceleration propellant dynamics using VOF methods and coupled heat and mass transfer
• Derive tank pressurization concepts from mission requirements and reusability constraints
• Perform NPSP and inlet margin trades, considering propellant thermal state and transient conditions
• Analyse propellant routing, including feedlines and valves, focusing on transients and reuse robustness
• Define pressurization and consumables architecture, including sizing logic and operational envelopes
• Develop reduced order models from high-fidelity analyses to support vehicle-level trade studies

Requirements

• Degree in mechanical, aerospace, or chemical engineering
• 3–5 years of experience in propulsion, fluids, or propellant management
• Strong fundamentals in fluid mechanics, thermodynamics, and cryogenic systems
• Solid understanding of multiphase flow, liquid–vapor interfaces, and heat/mass transfer
• Practical experience with VOF or comparable multiphase modelling
• Experience with tank pressurization architectures and transient behaviour
• Experience abstracting high-fidelity analysis into reduced order models
• Fluent in English (German is a plus)

Preferred Qualifications

• Exposure to microgravity or low-acceleration propellant dynamics
• Ability to quantitatively assess trade-offs using first-principles analysis and scaling laws

Benefits

• Employee Participation Program (virtual company shares)
• 30 days of vacation
• Company pension plan with 20% employer contribution
• Subsidised lunch
• Fully financed Deutschlandticket for public transport
• Sponsored sports club memberships (EGYM Wellpass)
• Individual learning allowance
• Childcare allowance

About the Company

Isar Aerospace is at the forefront of New Space, building a modern space business to enable faster, better, and cheaper access to space. We provide sustainable and environmentally friendly launch solutions for small and medium-sized satellites into Low Earth Orbit.