Note: The job is a remote job and is open to candidates in USA. SandboxAQ is a high-growth company delivering AI solutions that address some of the world's greatest challenges. They are seeking a hands-on computational scientist or engineer to lead the CFD Algorithm Development Project, which focuses on building AI-driven, physics-based optimization tools for next-generation catalytic reactors.
Responsibilities
• Develop Differentiable Solvers: Lead the creation of differentiable CFD frameworks in JAX, extending capabilities to complex geometries and non-periodic boundary conditions using immersed boundary methods
• Scalable GPU Engineering: Design, implement, and containerize code (Docker/enroot) to ensure reproducibility and scalability across multi-node GPU HPC environments
• Numerical Optimization: Develop optimized parallel linear solvers (FFT or matrix decompositions) and gradient-based scripts to iteratively modify reactor designs based on catalyst activity
• Validate & Benchmark: Rigorously validate simulation accuracy against benchmark results and fixed-bed reactor configurations for both non-reactive and reactive flow regimes
• Cross-Functional Collaboration: Partner with AI model developers to integrate property predictions and generate comprehensive technical reports summarizing algorithm scalability and differentiability
Skills
• PhD or MS in Computational Physics, Mechanical/Chemical Engineering, Computer Science, or equivalent
• 3+ years (including PhD) of hands-on experience in CFD code development, specifically on GPUs
• Proven ability to build scalable software on multi-GPU systems using JAX, PyTorch, CUDA, or MPI frameworks
• Full fluency in numerical linear algebra, PDE numerical methods, sparse/dense linear solvers, and immersed boundary methods
• Excellent Python programming skills, with JAX proficiency as a prerequisite
• Ability to manage multiple deliverables and produce clear technical documentation for milestone reviews
• PhD + 3 years of industry experience in a related computational field
• Proven expertise in non-isothermal flow, transport equations, and chemical reactor multi-physics (e.g., mass transport in fixed-bed systems)
• Expertise in adjoint optimization or auto-diff for gradient-based optimization of complex CFD objectives
• Experience with the full stack of scientific development, including CI/CD, unit testing, and deployment via K8s, Slurm, or Google Cloud Batch
• Demonstrated ability to deliver complex project milestones and publish high-quality technical results
Benefits
• Comprehensive medical, dental, and vision coverage for employees and dependents with generous employer premium contributions
• Retirement savings with company matching
• Paid parental leave
• Inclusive family-building benefits
• Flexible paid time off
• Company-wide seasonal breaks
• Support for flexible work arrangements that enable sustainable performance
• Opportunities for continuous learning and growth through on-the-job development, cross-functional collaboration, and access to internal learning and development programs
Company Overview
• SandboxAQ develops AI and quantum technology solutions that enhance biopharma, cybersecurity, and materials science. It was founded in 2016, and is headquartered in Palo Alto, California, USA, with a workforce of 51-200 employees. Its website is https://www.sandboxaq.com.
Company H1B Sponsorship
• SandboxAQ has a track record of offering H1B sponsorships, with 7 in 2025, 6 in 2024, 3 in 2023, 5 in 2022, 1 in 2021, 5 in 2020. Please note that this does not guarantee sponsorship for this specific role.