Thermally developing flow of Al2O3-water nanofluid through regular N-sided polygonal ducts: A semi-analytic weighted residuals approach

- A semi-analytical method is developed for developing flow in polygonal ducts.
- Closed-form solutions for the flow and temperature fields are obtained.
- Both constant wall temperature and uniform heat flux boundary conditions are used.
- Nusselt numbers along the axial direction for various duct geometries are presented.
- Heat transfer enhancement with increasing nanoparticles volume fraction is observed.