Due to recent bot attacks we have changed the sign-up process. If you want to participate in our forum please send a message via our contact form. › Forums › OpenLB › General Topics › Mometum Exchange by Epsilon › Reply To: Mometum Exchange by Epsilon October 27, 2025 at 7:22 pm #10902 mathiasKeymaster Please chech that line in the code: Vector externalAcceleration = {.0, .0, -T(9.81) * (T(1) – physDensity / cubeDensity)};