(Heat Transfer in Circular Ducts and Tubes). The length of the paper should not exceed 1200 words for which just a page worth of words (275) should be enough from these highlighted parts. However, do include cited images, charts, graphs, etc. to express the content in section 5 with further detail, as they are required for a proper engineering research paper. Moreover, equations are extremely important for the heat transfer correlation and heat transfer efficiency (5.a, and 5.b). Since this is an engineering paper, at least one equation for each of these sub-points is required, with each of its variables/components explained, this should be the main focus for these points considering the low amount of words, a well explained equation is able to satisfy these tasks. I suggest consulting \”Heat and Mass Transfer: Fundamentals and Applications\” by Cengel for these equations if not specified in the sources highlighted.