A detailed computational analysis is carried out on the heat transfer and pressure loss of a turbulent flow in detached pin fin arrays with various clearance values for the Reynolds number range of 20,000–80,000 and the rotation number range of 0–0.3. Clearances exist at the midheight of the detached pin fins, which account for 10%, 15%, and 20% of the full pin fin's height, respectively. The clearances release the fluid stagnation and reduce the bulk flow turbulent mixing level, which significantly reduces the pressure loss. Compared with the pin fin arrays, the pressure loss is decreased by up to 30.5% with the increase of the clearance value for the detached pin fin arrays. Also, the detached pin fin arrays show a maximum increase in the total Nusselt numbers by about 13.5%. Furthermore, the rotation effects can increase the friction factors as well as the Nusselt numbers simultaneously in both the pin fin arrays and the detached pin fin arrays. A higher rotation number can promote the heat transfer enhancement and uniformity in the detached pin fin channels.