Thermodynamic and Kinetic Behavior Study of Gas Bubbles in High‐Temperature Steel Melts

Abstract

This study provides an exhaustive exploration of the thermal expansion of low‐temperature argon bubbles in high‐temperature molten steel and the resulting dynamic effects. The energy equation of compressible fluid simultaneously with the volume of fluid model under the Euler framework is solved. The generation and rising behavior of bubbles are validated through rigorous physical water model experiments. Findings reveal that, within a heating time of 0.2–0.45 ms, gas bubbles already complete 65–90% of their internal energy increase. The total heat transfer time and heat transfer coefficient of bubbles exhibit distinctive patterns influenced by the initial diameter and temperature of the bubbles. Specifically, under the conditions studied, bubbles exhibit a total heat transfer time of ≈20–60 ms, accompanied by a heat transfer coefficient ranging from 500 to 2600 W (m2 * K)−1. During the thermal expansion process, gas bubbles experience energy transfer and conversion within the two‐phase flow. This article establishes a dynamic model describing bubble thermal expansion in steel melts based on underwater bubble dynamics’ first principles. The model provides a quantitative depiction of instantaneous changes in bubble size, velocity, and kinetic energy under specific conditions.