الفهرس 
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Abstract
The current study presents a simple control model of the acceleration maneuver of submerged (Defense Advanced Research Projects Agency) DARPA SUBOFF using propeller INSEAN E1658 in calm water at different operation conditions, in addition, underwater acoustic analysis is used to calculate non-cavitating acoustic radiated from
propeller during acceleration. Empirical formulas are used to build the hull of DARPA SUBOFF with the propeller. The acceleration maneuver of DARPA SUBOFF, which is triggered at velocity 1.2 m/s and RPS 15 rev/sec, is simulated by using Wetted flow analysis with k-𝜔 SST turbulence model to calculate the minimum pressure on propeller blades at specific scenarios of change in RPS. In addition, empirical methods are coupled to estimate the minimum pressure on the propeller blades at any condition. The developed model of acceleration provides avoidance of tip vortex cavitation and reduction of non-cavitating noise radiated from the propeller during acceleration. Noise generated from underwater vehicles plays a vital role in the detection of vehicles and is often related to harmful effects on marine life in addition to marine pollution. Underwater vehicles typically experience many causes of underwater noise such as noise from machinery, crew noise, and underwater propulsion noise. Propellers are considered the main source of underwater noise because of operating in different conditions of depth, temperature, quality of water, and the number of rotations. Also, the non-uniform inflow field due to the wake field is mainly caused by the boundary layer around the hull of the vehicle. The acceleration of underwater vehicles is one of the critical operation phases in which underwater propellers face unsteady conditions of inflow field besides the gradual or sudden change in the number of rotations per second. In this work, DARPA (Defense Advanced Research Projects Agency) SUB OFF (Groves, 1989) with INSEAN E1658 is generated using CAESAS. the numerical set-up is validated using STAR-CCM+ and the results are compared with those of the experiments results(Liu & Huang, 1990). Different simulations of acceleration for DARPA using wetted flow analysis with instant RPS increase, linear increase RPS, parabolic RPS increase, and increase of RPS with tanh relation are introduced. Therefore, the minimum pressure coefficient on the propeller and the reduction of pressure on propeller blades with increasing RPS can be extracted by multivariable regression. Then, a mathematical model of pressure reduction and pressure fluctuation can be found to control the acceleration of DARPA to reduce noise and prevent cavitation. The last step in this study is to compare the noise radiated from DARPA different scenarios of acceleration and those generated by the new control model using a hybrid method between CFD and P-FWH. The control of underwater vehicle acceleration is based on a model for controlling the temporal increase of the RPS. The model must be able to consider the cavitation related operation conditions such as the operating depth of SUB OFF, the water temperature, the actual and the demanded RPS. The controlled acceleration model consists of two tanh equations, these equations are connected in series. Also, there is a sudden increase in RPS at the beginning of the acceleration to reduce the time needed for fully developed RPS. In addition, the controlled system shows that acceleration avoids cavitation inception because the minimum pressure on the propeller blades is always more than the vapor pressure. the hybrid method, which combines CFD and P-FWH is used to calculate the acoustics pressure and estimate the radiated noise from the propeller. The non-cavitating acoustic radiated from the controlled model in the first case study is compared at two different scenarios with the same range of change in RPS. The noise radiated from the control model is lower than that at the different scenarios which is suitable to use in acceleration.