A novel reactor technology for steam cracking reactors, called Swirl Flow Tube (SFT), has been evaluated experimentally and computationally. A comprehensive experimental dataset has been acquired on a newly built test set-up covering a wide range of Re numbers (30,000–120,000) and different swirl flow tube designs. The swirl flow tubes result in an increase of heat transfer by a factor of 1.2–1.5 compared to a straight tube. The increased heat transfer is accompanied by an increased pressure drop by a factor 1.4–2.2 compared to a straight tube depending on Reynolds number and geometry. A computational fluid dynamics model was adopted that is able to capture the main flow properties of the swirl flow tube and this model allows to attribute the increased heat transfer and pressure drop to a higher wall shear stress. The experimental and simulation results confirm the great potential for the application of the SFT technology in steam cracking furnaces because of the lower average wall temperatures and the resulting reduction of coke formation in the reactor coil.