BRIDGE · Bubble-induced heat tRansfer enhancement for Immersion-cooleD data centers: A strateGy to Enhance thermal performance

The proposed project BRIDGE aims to pioneer a transformative approach to two-phase immersion cooling by employing induced bubble injection, where a secondary immiscible liquid is introduced to actively generate bubbles and enhance heat transfer performance. This represents the first systematic investigation of controlled bubble generation via secondary liquid injection, going beyond existing studies focused on gas-injected flows or stratified multi-fluid systems. By unlocking tunable and highly efficient heat transfer mechanisms, BRIDGE targets significant advances in data centre cooling and extends to broader applications, including electric vehicle batteries and nuclear thermal management.The project will integrate experimental investigations with multi-scale modelling across four research objectives (ROs): (RO1) establish proof-of-concept by quantifying heat transfer enhancement using high-speed imaging and infrared thermography; (RO2) develop and validate reduced-order and population balance models to predict bubble dynamics and void fraction; (RO3) examine the influence of induced bubble injection on key boiling characteristics such as onset of nucleate boiling (ONB), critical heat flux (CHF), and power usage effectiveness (PUE); and (RO4) derive dimensionless heat transfer correlations for design and optimization.Through modular experimental testbeds, advanced diagnostics, and statistical modelling, BRIDGE will deliver validated predictive tools and design guidelines for next-generation immersion cooling technologies. The project aligns with the MSCA PF objectives by advancing EU leadership in sustainable thermal management, fostering interdisciplinary skills in two-phase flows, heat transfer, and data-driven modelling, and strengthening collaboration between academia and industry. By improving cooling efficiency and reducing energy demands, BRIDGE supports the EU’s Green Deal and digital transformation priorities.