Senior Thermal Engineer

Firmus Technologies Firmus Technologies is a global leader pioneering the solution to AI’s energy challenge, founded in Australia in 2019 by a visionary team of entrepreneurs. Our mission is to create the most energy-efficient AI infrastructure, combining cutting edge technology with a steadfast commitment to sustainability. Through ground-breaking research and development, we invented a verticalised AI Factory - a new class of digital infrastructure that replaces traditional data centres. Built on new approaches to liquid cooling, energy management, water use and modular construction methodology, the Firmus AI Factory delivers low-cost AI tokens across Asia-Pacific. Firmus AI Cloud We provide customers access to energy savings via our large-scale GPU cloud, Firmus AI Cloud. Rated Silver in The GPU Cloud ClusterMAX™ Rating System, our cloud empowers developers, enterprise, education and government users to train AI models with unmatched efficiency and cost savings. With an ever-growing list of services and applications, we are committed to building a cloud experience for our customers that is market-leading, proprietary and built to scale. Why you’ll love working here • A fast-paced and dynamic environment working with next-gen technology. You’ll be operating at the intersection of sustainability and artificial intelligence – helping to transform an industry. • Working with and access to colleagues who are true innovators and leaders in their field. • As an emerging company, we work as a close-knit team. Work with the founders, grow a strong network, and witness the impact you make first-hand as we democratise AI tools for everyone – more sustainably, and more affordably. We believe that people from diverse backgrounds come together to do their best work, be their authentic selves, and build great things. We are proud to be an equal opportunity employer. Role Summary Firmus Technologies is seeking a highly experienced Senior Thermal Engineer with deep experimental and numerical thermal management expertise to lead thermal design and optimization of our revolutionary AI Factory infrastructure. The successful candidate will have exclusive access to our state-of-the-art AI cluster featuring A100 and A400 GPUs, enabling large-scale, high-fidelity CFD simulations using ANSYS Fluent with exceptional computational power. You will drive thermal management initiatives for AI systems exceeding 100kW per rack density, designing and validating cutting-edge liquid cooling architectures including direct-to-chip cooling, immersion systems, and hybrid solutions. You will provide technical leadership to cross-functional teams, drive innovation in thermal design across all heat transfer modalities and length scales and lead experimental validation campaigns. Additionally, you will develop predictive thermal models and comprehensive digital twin development in CFD incorporating the latest ML predication capabilities to support future prediction and operational optimization, while championing sustainable cooling innovation to minimise Power Usage Effectiveness (PUE). Skills & Experience • Higher level degree in Mechanical Engineering, Thermal Engineering, or related field with focus on heat transfer and fluid dynamics • Minimum 8+ years of experience in thermal management for data center and high-performance computing applications • Deep expertise in ANSYS Fluent with proven ability to execute large-scale, complex CFD simulations • Extensive experience in liquid cooling technologies including cold plates, heat exchangers, and cooling distribution systems • Strong background in experimental thermal testing, instrumentation, and data analysis • Proven track record of thermal design for electronic systems with power densities >50W/cm² • Experience with multi-physics simulations combining thermal, fluid flow, and structural analysis • Proficiency in CAD software (SolidWorks, AutoCAD) and programming languages (MATLAB, Python) • Strong publication record in peer-reviewed journals and conference presentations • Excellent communication skills with ability to present complex technical concepts to diverse audiences Application process Interested candidates should submit a comprehensive application including: (i) detailed CV highlighting thermal management experience, (i) portfolio of CFD simulation work, (iii) list of publications and conference presentations, and (iv) cover letter explaining your interest in sustainable AI infrastructure development. Location & Reporting • Location: this position is based at our Singapore headquarters with potential for international travel to AI Factory sites globally. • Reports to: directly to the Head of Engineering with close collaboration to the CTO and the engineering leadership team. Employment Basis Permanent full-time Diversity At Firmus, we are committed to building a diverse and inclusive workplace. We encourage applications from candidates of all backgrounds who are passionate about creating a more sustainable future through innovative engineering solutions. Join us in our mission to revolutionise the AI industry through sustainable practices and cutting-edge engineering. Apply now to be part of shaping the future of sustainable AI infrastructure.