Pulse detonation rocket engines (PDREs) have attracted considerable research interests in recent years as chemical propulsion systems potentially offering improved performance and reduced complexity compared to conventional steady-state liquid rocket engines. An experimental investigation was carried out on a multi-cycle pulse detonation rocket engine test model, running on a liquid kerosene-oxygen mixture using a solenoid-valve injection system and a low-energy ignition source, to investigate the effectiveness of Shchelkin spiral on the Deflagration to Detonation Transition (DDT) process. Detonation frequency of test model was fixed in 10Hz. Automobile spark plug was used to ignite the detonative mixture, and the ignition energy was around 5OmJ. The pressure was measured by piezoelectric pressure transducer. The results showed that Shchelkin spiral was able to achieve successful DDT in the detonation tube. In addition, a Phantom V7.2 CMOS color digital high speed video camera was used to record the exhaust plume of PDRE test model.