1. The problem statement, all variables and given/known data I have a radiator through which water is passed at 90 degrees Celsius, the air speed as it passes through the radiator is 4ms-1. Water temperature difference between inlet and outlet of radiator is 28.33 K. Temperature difference between air before and after passing through radiator is 29K. Area of radiator core is 2.88 x 10^-2 m^2. 2. Relevant equations Equation for heat transfer = W*Cp*ΔT where W is weighted flow and Cp is specific heat capacity of fluid. For water heat transfer is = WCpΔT = QwpwCpΔT, where Qw is volumetric flow rate of water, pw is density of water and Cp is specific heat capacity of water at 90 degrees celcius. so Qw = 2.5 x 10-5 m3s-1 pw = 1.0 kgm-3 Cp = 4.21 ΔT = 28.33 K For air heat transfer is = WCpΔT = = Ar v CpΔT, where Ar is the surface area of radiator core, v is the velocity of air as it passes through the radiator core, Cp is the specific heat of air so Ar = 2.88 x 10^-2 v = 4.0 ms-1 Cp = 1.0 ΔT = 29.0 K 3. The attempt at a solution Heat transfer of water = 2.98 x 10^-3 kWatts Heat transfer of air = 3.34 kWatts. why am I getting such a huge difference between heat transfer of the two fluids ? are my equations wrong ?