Abstract: This paper gives a general remark on the current knowledge of forced convective heat transfer. Experimental data for showing dependence of heat transfer on the direction of temperature gradient with turbulent flow of water through circular tube and concentric annuli are presented. Method of correlation has been well defined and discussed, and the results are compared with McAdam's and Mikheyev's recommended formulae. As a result of this preliminary investigation, the following conclusions are presented: 1. With the heat transfer coefficient based on the logarithmic mean value of inlet and outlet temperature difference between fluid and surface, the experimental data for both parallel flow and counter flow can be correlated together. 2. For water and other liquids of low viscosity, data for heating and cooling could be brought together more effectively by introducing the term as a correcting factor for the dependence of forced convective heat transfer on direction of heat flow. 3. The McAdam's and the Mikheyev's recommended formulae [eq. (7) and (8)] are well adaptable for heating water in turbulent flow through tube; while for cooling, the heat transfer coefficient may be calculated as o.8 of that for heating. For both heating and cooling water, eq. (14) can be recommended. 4. The experimental data presented for the heat transfer coefficient at the inner wall of concentric annuli deviate from the McAdam's and Mikheyev's recommended formulae, yet agree with Davis' eq. (18).