Heat Transfer to Liquid Metals in a Thermal Entrance Region

The purpose of the present work is to explore analytically and experimentally the heat transfer to liquid metals in turbulent flow within the thermal entrance region of circular tubes having uniform wall temperature. Since liquid metals are characterized by high thermal conductivity, emphasis has been placed on analytical conduction solutions which neglect the contribution to heat transfer that is made by the eddy motion of a fluid in turbulent flow. Three solutions, which differ only in the postulated velocity distribution of the fluid, have been selected for comparison. The postulated velocity distributions are: (l) uniform, (2) parabolic and, (3) velocity proportional to distance from the channel wall raised to the one-seventh power. The third distribution is usually referred to as the one-seventh power law distribution. Other related entrance region solutions are briefly surveyed.