Steam in a heating system flows through tubes whose outer diameter is $5$ cm and whose walls are maintained at a temperature of tube. The space between the fins is $3$ mm $,$ and thus there are $250$ fins per meter length of the tube. Heat is transferred to the surrounding air at $T_{}=25C,$ with a heat transfer coefficient of $40\frac{W}{m^2}*K.$ Determine the increase in heat transfer from the tube per meter of its length as a result of adding fins.

Efficiency of straight fins of rectangular, triangular, and parabolic profiles.

The increase in heat transfer from the tube per meter of its length as a result of adding fins is $$ W$.$