Numerical investigation of heat transfer and flow inner tube with periodically cosine oscillation

In the present study, both heat transfer and pressure drop was studied numerically for static round tube and cosine oscillating tube with finite volume method. The effect of dimensionless amplitude and frequency on heat transfer and pressure drop was also investigated for Reynolds number changing from 6170 to 14,000. Under the influence of cosine oscillation, the heat transfer and pressure drop is periodically changing and the frequency for heat transfer and pressure is half of that for cosine oscillation motion. Heat transfer was enhanced by cosine oscillation and increased by 1.9% compared to static tube for Re = 6140. Meanwhile, heat transfer increased by 35% as dimensionless amplitude increased from 1 to 10. While cosine rotation also caused larger pressure drop and the pressure drop for cosine oscillating tube is 3.01% that of static tube. The pressure drop is proportional to dimensionless amplitude and frequency. However, heat transfer first reduce and then increase with increase in frequency.