HAAR Recruitment
Website:
hellohaar.com
Company:
https://www.linkedin.com/company/haar-recruitment
Industries: IT Services and IT Consulting
Job details:
*Applicants must have a Waste Water or Similar industry background*
Job Description
Reporting to the Director of Product, we are seeking a hands-on modeler to build and
calibrate the equation-oriented mechanistic models and forward simulators at the
heart of our physics engine, the foundation for physics-informed optimization in real
operational settings. This role turns physical processes into rigorous, trustworthy
Python models that our optimization and AI systems rely on.
This is a builder role, not a research-only position. Success is measured by validated,
production-grade models that run in real systems and produce customer value.
Adjacent titles you may recognize this role by: Process Simulation Engineer,
Computational Scientist / Computational Modeling Engineer.
Duties and responsibilities include:
- Building equation-oriented mechanistic models of unit processes including transport, separation, fouling accumulation, and cleaning/recovery dynamics, in Python
- Developing forward dynamic simulators that predict process behaviour over operating cycles
- Calibrating and validating models against real operating data with our process engineers, and running parity checks against ground truth
- Contributing fast surrogate and hybrid (physics-informed) model components where full-order simulation is too slow for real-time use
- Supplying the simulation, residual, and validity outputs that our optimization layer consumes
- Performing parameter estimation and uncertainty quantification, and clearly communicating model assumptions, validity ranges, and confidence
- Participating in peer-reviews of model designs and related code
- Analyzing and resolving technical modelling problems
- Writing production-grade, well-tested, version-controlled Python that meets our engineering standards
Core Requirements
- Master's degree, or 3+ years of relevant experience, with a strong foundation in mathematics and either mechanical or chemical engineering (or physics / applied mathematics with equivalent transport and thermodynamics grounding)
- Strong applied mathematics: differential equations, numerical methods, linear algebra, and optimization fundamentals
- Demonstrated ability to translate physical or chemical processes into governing equations and solve them numerically
- 3+ years Python software development for scientific computing (e.g., NumPy, SciPy)
- Hands-on experience building and calibrating simulation or process models against real data
- Comfortable with test-driven development and unit testing
- Comfortable working with real-world data
- Comfortable working with a globally-distributed team across multiple time zones
- Comfortable working independently and capable of self-direction
- Collaborative mindset and ability to work closely with domain experts and communicate technical information clearly
- Evidence-based attitude and ability to define problems and metrics and quantify results
Secondary Requirements
- Equation-oriented / acausal modeling experience with tools such as Pyomo, IDAES, WaterTAP, gPROMS, Aspen Custom Modeler, or CasADi
- Experience with derivative-based solvers (e.g., IPOPT) and large sparse nonlinear or mixed-integer systems
- Membrane process modeling (e.g., RO/UF): fouling, concentration polarization, flux-decline models, backwash or clean-in-place dynamics, or remaining-useful-life prognostics
- Experience with physics-informed machine learning, surrogate modeling, or model-order reduction
- Exposure to model predictive control (MPC) or reinforcement learning
- Experience in an industrial process control setting
- Familiarity with parameter estimation and uncertainty quantification
- Experience with water or wastewater treatment processes is a plus, but our process engineers provide domain knowledge, so it is not expected
- Familiarity with AI-assisted coding (Cursor, Claude Code, Codex)
Click on Apply to know more.