Same 0.65 % air, different bubbles: aeration simulation with optical data | PW Experience 2026

Direct Optical Air-in-Oil Measurement as an Enabler for Accurate Simulation of Gearings and Hydraulic Systems Dr. Lukas Hafner & Gianluca Parma — deepfluid (DE) – EnginSoft SpA (IT) Particleworks Experience 2026, Modena, 7 October 2026 Key findings: • The same air content (0.65 %) can hide 132 µm or 68 µm bubbles, and with them 18 or 32 m² of oil–air contact surface: oxidation, cavitation and compressibility follow the surface. • The Particleworks aeration model is calibrated on total air and bubble-size distribution: in a differential gear 0.12 % / 800 µm became 0.45 % / 186 µm against 0.43 % / 180 µm measured. • Coefficients scale with speed and not with geometry; a new additive package needs a new calibration, and the temperature dependence (even its sign) is an open point. Chapters: 0:00 Introduction and speaker 5:25 Same air, different bubbles 12:12 Calibrating the model 14:18 The differential gear 18:58 Before vs after calibration 21:56 Q&A: new additive, new calibration 24:22 Additives and temperature The story of the day (quotes, slides, moments): https://particleworks-europe.com/blog... Slides and all talks: https://particleworks-europe.com/expe... Particleworks Europe, meshfree CFD: https://particleworks-europe.com #Particleworks #MPS #CFD #Simulation #ParticleworksExperience #Aeration