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In this thesis,the performance analysis of wind-assisted ship propulsion is undertaken.Amongst various types of wind-assisted propulsion systems,the Flettner rotor is the most promising technology and thus forms the core of this research.Flettner rotor has been the subject of many studies by different researchers and scientists in the shipping industry.This study is carried out via a series of literature survey,formulation of the behavior of Flettner rotor,modeling of a ship with Flettner rotor using Matlab tools,and finally validation of the results with actual data from a ship.The modeling is based on a route-based analysis of a Flettner rotor’s cylinder with and without endplate.For this purpose,the relevant Matlab R2016a editor live functions were developed and then solved using coding with the input variable technique.In this study,data for the Yu Peng Training ship of Dalian Maritime University,and on its route from Dalian in China,through Tianjin to Richard-bay in South Africa,was used to determine and estimate the power generated and consumed by Flettner rotor.The study simulates the ship using a Flettner rotor with a height of 18 m and a diameter of 3 m,and with an endplate of 1.5 m using several Flettner rotor’s velocity ratios（1≤Cr≤8）,endplate sizes（1≤DE≤4.5 m）and various true wind angles（0≤De≤360 degrees）.The results of predictions indicate that for Flettner rotor without endplate,as the coefficient of rotation increases the power generation decreases,while power consumed increases;thus leading to reduced overall net power by the Flettner rotor.Also,the power generated and consumed with different endplate Flettner rotor sizes indicates an increase in power generated and a decrease in power consumed as the size of endplate increases.Predicted data on power generated and consumed with the different fixed conditions on route-based,are also calculated and shown in polar graph and their features are described as part of this study.For Yu Peng ship predictions,the coefficient of rotation Cr=2,and DE=1.5 m endplate diameter size,were used to estimate power generated and power consumed by the Flettner rotor.The ship speed of 14 knots,and average true wind speed in route from South Africa to Dalian through Tianjin estimated in fifteen-day of a month（April）be 6.2 m/s,the cylinder height H=18 m,diameter=3 m,aspect ratio AR=6,the average power generated is 46.2 k W and power consumed is 17.8 k W for a Flettner rotor without an endplate;and average power generated is 42.6 k W and average power consumed is 17.82 k W for same Flettner rotor with endplate.Results indicate that developing a route model for Yu Peng ship from the Richard-bay port to Dalian port,which incorporates resistance models（frictional resistance,residual resistance and appendage resistance）for evaluating fuel consumption reduction（in case modeled1.13%）and emission impact in real-time is feasible.This study confirms that there is a good potential for use of a Flettner rotor to harness wind energy for ship propulsion.It also indicates the possibility to reduce ship fuel consumption and greenhouse gas（GHG）emissions that are key to fight climate change and limit global warming.The study also showed that engineering models can be developed and used for design studies for performance evaluation.