The present study proposed some novel designs that can surpass the most widely used louver fin geometry for air-cooling applications. Innovative fin types such as ring fins, circular disk fins, and hexagonal disk fins are numerically modeled and compared with a louver fin-and-flat tube heat exchanger in terms of thermal resistance in the same pumping power. Flow visualization is also carried out by particle image velocimetry (PIV) method for hexagonal disk fins for qualitative validation. Results show that although ring fins can force the airflow toward the flat tubes, they are not able to effectively reduce thermal resistance. Meanwhile, using four circular disk fins can yield a lower thermal resistance by up to 16%. The delta winglets can be added onto the circular disk fins for further augmentation. The hexagonal disk fins can also offer similar improvement like circular disk fins but include some unique features for easier fabrication and assembly with the maximum penalty of 4% increase in thermal resistance relative to the circular disk fins. The flow visualization by PIV method is performed for inline hexagonal disk fins, which qualitatively confirms the numerical simulations regarding the proposed novel fin patterns.