EXPERIMENTAL INVESTIGATION OF ENHANCEMENT HEAT TRANSFER OF INSERT TWISTED TAPE OF CIRCLAR CUT WITH WIRE COIL IN THE DOUBLE PIPE HEAT EXCHANGER. J. eng. sustain. dev. 2018;22(3):Pages 23-33. Accessed May 15, 2024. https://jeasd.uomustansiriyah.edu.iq/index.php/jeasd/article/view/321