Tailored nanoparticles can be synthesized through flame spray pyrolysis (FSP), a heterogeneous spray combustion process known for its advantages, including high product purity and operational flexibility. FSP allows for controllable material properties and the synthesis of metastable phases. Although various materials and their applications have been explored in laboratory-scale reactors, scale-up studies remain limited, and transitioning from lab-scale (g/h) to industrial-scale (kg/h) production while maintaining nanoparticle characteristics is challenging. A thorough understanding of the synthesis process is essential for this transition. Investigating fluid dynamics, combustion, and particle dynamics is crucial to uncover the mechanisms influencing particle properties. Computational fluid dynamics (CFD) serves as a powerful tool to gain insights into the physical and chemical phenomena occurring across different time and length scales. This work combines CFD techniques with population balance models (PBM) through a systematic methodology that accurately represents the heterogeneous spray combustion process. The CFD-PBM approach is employed to analyze the evolution of nanoparticle properties during the FSP process, focusing on how various operating conditions affect particle residence time in high-temperature regions and the relationship between particle properties and high-temperature particle residence time (HTPRT).
