Gas–liquid two-phase flow–solid coupling process at the inclined T-junction pipelines

Inclined T-junction pipelines are commonly used to separate gas–liquid phases. This study combines theoretical analysis with numerical simulations to explore the structural stability of the inclined T-junction pipelines. Dimensional analysis reveals that the inlet flow velocity, flow split ratio, gas inlet volume fraction, and bubble diameter all influence the flow within these pipelines. In addition, a flow–solid coupling simulation method, which considers the instability of the gas–liquid two-phase flow, was developed to study the effect of these four factors above on the structural stability of the inclined T-junction pipelines. The results indicate that applying fixed constraints to both ends of the main pipeline reduces the risk of resonance and significantly enhances structural stability. Within certain limits, increasing the inlet velocity leads to higher fluid dynamic pressures and impact forces. The flow split ratio notably affects the pipeline’s load and stress levels, which, in turn, influence the flow–solid coupling effects. The other two factors of gas inlet volume fraction and bubble diameter have little influence on the stability of the inclined T-junction pipeline structure, which can be ignored. These findings are valuable for designing the flow parameters of multifurcated pipelines in engineering applications, ensuring safe and efficient pipeline system operation.