The Performance of the U Shape Double pipe heat exchanger under effect of using Active Techniques. NTU Journal of Engineering and Technology, [S. l.], v. 1, n. 3, 2022. DOI: 10.56286/ntujet.v1i3.61. Disponível em: https://journals.ntu.edu.iq/index.php/NTU-JET/article/view/61.. Acesso em: 9 apr. 2025.