THERMAL SCIENCE

International Scientific Journal

Thermal Science - Online First

Zhaoliang Zang

,

Shi Xiang

,

Kiumars Khani Aminjan

,

Samira Marami Milani

,

Antonio Zuorro

online first only

Numerical investigation of interaction between internal mixing air and spray of three kinds of fluids

ABSTRACT
The widespread use of atomizers for fuel spraying in combustion chambers or water spraying for cooling purposes has made them attractive subjects for research. This study investigates the interaction of internal mixing high-velocity airflow with the spray of three fluids in a pressure swirl atomizer. The research was conducted using the numerical solution method, supported by experimental data, which demonstrated good agreement between the simulation and experimental results. The findings revealed that adding 0.02 kg/s of high-velocity airflow at 300 K to the spray of three liquids-namely water, normal heptane, and kerosene-each at a mass flow rate of 0.08 kg/s, reduced the fluid film thickness (T) by 79.82%, 77.36%, and 76.87%, respectively. This reduction subsequently resulted in a significant decrease in the Sauter mean diameter (SMD) by 96.99%, 96.12%, and 95.94%, respectively. Additionally, the results indicated that the addition of high-velocity airflow slightly increased the spray cone angle for kerosene and normal heptane, but caused the water spray to collapse and move out of its intended pattern. The study also found that high-velocity airflow dramatically increased the turbulence kinetic energy (TKE) for the spray of all three liquids, with a more pronounced effect observed in the water spray. These results can guide researchers in understanding the effects of high-velocity airflow on spray dynamics and assist engineers in designing and manufacturing atomizers with optimal performance.
KEYWORDS
interaction, internal mix, high-velocity airflow, kerosene, normal heptane, fluid film thickness, SMD
PAPER SUBMITTED: 2025-03-15
PAPER REVISED: 2025-06-30
PAPER ACCEPTED: 2025-07-31
PUBLISHED ONLINE: 2025-08-02
DOI REFERENCE: https://doi.org/10.2298/TSCI250315139Z
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Numerical investigation of interaction between internal mixing air and spray of three kinds of fluids