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In present study, the wake flow field of a submarine model was investigated experimentally in a wind tunnel. These experiments were conducted in four different locations X/L= 0.85, 1, 1.25 and 1.5 downstream of the model at Reynolds number of 3.85×105 by a five hole probe. The effect of various factors such as the variation of Reynolds number, the installation of the trip strip on the model nose surface, the mounting of the appendages on the submarine bare hull model and the nose shape effect on the wake structure were investigated in this study. The results showed that the installation of the trip strip on the nose surface did not have recognizable effects. By Increasing the Reynolds number, the amount of the dropping velocity in the wake field decreased due to the decreasing of the separation region on the after-body section. Presentation of the appendages on the model surface lead to the increasing of the wake area. The effect of the nose shape on the wake of the submarine model is the main innovation in the present work. Investigations showed that the velocity in the central part of the wake for non-axisymmetric nose shape (TANGO) decreased in comparison with the axisymmetric nose shape (SUBOFF and STANDARD).

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In the present study, the wake flow field of a submarine model was investigated experimentally in a wind tunnel. The experiments were conducted to determine the effect of the location of control surfaces on the wake inflow to the impeller of the submarine. In order to investigate the effect of the location of control surfaces as the most important innovation of the present study, the aforementioned surfaces were installed in three longitudinal positions X/L=0.89, 0.92, 0.95 on the heel of the submarine model, and the wake flow was measured at position X/L=1.7 and the Reynolds number 6*10^5  by a five-hole probe and a hotwire anemometer. Finally, the longitudinal position X/L=0.95 was selected as the optimal location for the stern planes to improve the wake inflow to the impeller in terms of reducing its total area and the least amount of turbulence and non-uniformity. The results obtained during this study showed that arriving of the holder basechr('39')s wake to the stern area increases ​​the area and average velocity and subsequently reducing the non-uniformity of the wake flow.