An uninsulated hot water pipe is suspended horizontally in a room. (a) (b) Using the data provided and properties of air from the table provided, determine the convective heat transfer rate from the pipe to the room per unit length of pipe. If the surface temperature of the pipe was increased to 36C, would you expect the heat transfer rate by convection to double? Explain your reasoning. Data for Question A1. Pipe surface temperature Pipe external diameter Room air temperature (c) Explain why expressions for free convection utilise the Grashoff Number whilst those for forced convection utilise the Reynolds Number. free convection over horizontal tube forced convection over horizontal tube where 80 C 80 mm 24 C 104 Gr Pr