In a thermal system, water enters a 25-mm-diameter and 23-m-long circular tube with a mass flow rate of 0.1 kg/s at 25 degree c. the heat transfer from the tube surface to the water can be expressed in terms of heat flux as q"s(x) = ax. the coefficient a is 400 w/m^3, and the axial distance from the tube inlet is x measured in meters. determine
(a) an expression for the mean temperature t_m(x) of the water,
(b) the outlet mean temperature of the water, and
(c) the value of a uniform heat flux q" s on the tube surface that would result in the same outlet mean temperature calculated in part (b). evaluate water properties at 35 degree c.
(d) discuss why water properties are evaluated at 35 degree c.
(e) evaluate the (c) and (d) when inlet temperature of water is 15 degree c.