This study presents a numerical investigation of a novel spiral finned heat exchanger (SFHE). The primary objective is to optimize the heat transfer efficiency of micro gas turbine recuperators by employing a spiral fin model. Through computational simulations (CFD), the study examines the variations in the Colburn j factor and Fanning friction f factor as the spiral fins alter. The results demonstrate that the SFHE exhibits superior heat transfer capacity and overall heat transfer performance compared to wavy fin models. At a Reynolds number of 1000, the JF factor of the spiral fin 35_125 is 70.47 % higher than that of a wavy fin at the same Reynolds number, and 34.03 % higher when the Reynolds number increases to 5000. The study also reveals that the cutting thickness of the top and bottom, denoted as C1, does not significantly impact the variable j, f. However, increasing the cut thickness C2 on the left and right sides results in a more compact model, leading to higher values of f, but the j-factor is almost unchanged. While decreasing the wavelength of the spiral fins can improve heat transfer efficiency, it also increases pressure loss, necessitating careful selection of wavelength for optimal SFHE design.