Norouz Mohammad Nouri - Associate Professor, Iran University of Science & Technology;
Mehrdad Kalantar Neyestanaki - Master of Science Student, Iran University of Science & Technology;
Saber Mohammadi - P.H.D Candidate, Iran University of Science & Technology;

Contra Rotating Propulsion System (CRP) consists of two propellers with counter rotation direction. The main advantage of CRP system is its higher efficiency compared to that of a single propeller system. In this system, propulsion efficiency is increased by removing the radial component of wake flow and changing it into axial propulsiveforce. Furthermore, the possibility of cavitation occurrence decreases by dividing the load between two propellers. Inaddition, it is required to balance the propulsion system torque in applications related to AUV (Autonomous underwatervehicle). The AUV body has significant effect on the performance of the propulsion system. The propellers have different performance and higher efficiency due to being located inside the resultant wake. This has led to reanalyzing thepropeller alongside the AUV bodies rather than employing the results for standard open water propellers. In order tonumerically analyze, computational fluid dynamics method has been used which is more precise compared to other methods like boundary element and K-ɛ RNG model is an appropriate model for simulating the turbulence flow

AUV, CRP, Computational Fluid Dynamics, RANS