The Research On The Characteristic Of Propeller In Abnormal Condition

When the vessel with multipropeller sailing on the sea,some accident may happen,including that some propellers are at work,but the others are out of work. In some reasons,we shoule try to predict these situations to establish the base for the vessel with multipropeller.Panel method and software FLUENT are used in the thesis to predict the capability of propeller,and then compared with the data from experiment. Though panel method is more approximate than FLUENT in prediction,FLUENT has more advantages in making simulation of capability of the propeller.FLUENT has been used to simulate and calculate the capability of propeller which lost one blade. And the transformation between the velocity coefficient has been researched. The pressure of propeller and the velocity on the surface of blade are also considered. In addition, when the propeller which lost one blade was locked, the resistance of propeller has been calculated by FLUENT software.The locked propeller has been reaserched by two ways,firstly,the velocity and the pressure on the surface have been simulated by FLUENT software ,and the path line behind the locked propeller has also been researched in detail. The resistance on the locked propeller has been caculated by Kermakefe method,and made comparision between the two method.In terms of the free rotational propeller,there are two phases in the whole process,the stationary and unstationary,when the velocity is certained,there is rotate speed bewteen the unstationary process and the stationary process,so the critical rotate speed must be found .The theory in the steady of rigid body can provide some help to solve the problem. After the critical rotate speed being found,we could summarize the rotational rule of propeller in defferent velocity. And the thrust and moment can be ensured.