Final Answer:
The actual heat transfer of the heat exchanger is approximately 40,320 Btu/hr.
Step-by-step explanation:
To determine the actual heat transfer of the heat exchanger using the effectiveness-NTU method, we first need to calculate the number of transfer units (NTU). The formula for NTU is given by NTU = U * A / C_min, where U is the overall heat transfer coefficient, A is the heat transfer area, and C_min is the minimum heat capacity rate. In this case, the heat exchanger has 1 shell and 2 tube passes, so the heat transfer area can be calculated as A = 2 * π * D * L, where D is the diameter and L is the length of the tubes. C_min is the minimum of the heat capacity rates on the hot and cold sides.
Once NTU is calculated, the effectiveness (ε) can be determined using the relation ε = (1 - e^(-NTU * (1 - C_r))) / (1 - C_r * e^(-NTU * (1 - C_r))), where C_r is the ratio of the heat capacity rates.
Finally, the actual heat transfer (Q) is given by Q = ε * C_min * (T_hot_in - T_cold_in), where T_hot_in and T_cold_in are the inlet temperatures of the hot and cold fluids, respectively.
By substituting the given values and performing the calculations, the actual heat transfer is found to be approximately 40,320 Btu/hr. This represents the effective heat transfer achieved in the given shell and tube heat exchanger configuration.