The speed of a ship sailing in waves always slows down due to the decrease in efficiency of the propeller. So it is necessary and essential to analyze the unsteady hydrodynamic performance of propeller in waves. This ...The speed of a ship sailing in waves always slows down due to the decrease in efficiency of the propeller. So it is necessary and essential to analyze the unsteady hydrodynamic performance of propeller in waves. This paper is based on the numerical simulation and experimental research of hydrodynamics performance when the propeller is under wave conditions. Open-water propeller performance in calm water is calculated by commercial codes and the results are compared to experimental values to evaluate the accuracy of the numerical simulation method. The first-order Volume of Fluid(VOF) wave method in STAR CCM+ is utilized to simulate the three-dimensional numerical wave. According to the above prerequisite, the numerical calculation of hydrodynamic performance of the propeller under wave conditions is conducted, and the results reveal that both thrust and torque of the propeller under wave conditions reveal intense unsteady behavior. With the periodic variation of waves, ventilation, and even an effluent phenomenon appears on the propeller. Calculation results indicate, when ventilation or effluent appears, the numerical calculation model can capture the dynamic characteristics of the propeller accurately, thus providing a significant theory foundation forfurther studying the hydrodynamic performance of a propeller in waves.展开更多
Electric propulsion is broadly defined as the acceleration of a working fluid for propulsion by electrical heating and/or by electric and magnetic body forces. Compared with chemical propulsion, electric propulsion ha...Electric propulsion is broadly defined as the acceleration of a working fluid for propulsion by electrical heating and/or by electric and magnetic body forces. Compared with chemical propulsion, electric propulsion has the characteristic of higher specific impulse, lower thrust, lighter weight and longer lifetime. So electric propulsion is generally suitable for satellite attitude control, the orbit transfer and raising, orbit correction, resistance compensate, position keeping, reposi- tion, space exploration and interplanetary flight.展开更多
基金Supported by the National Natural Science Foundation of China （51379043, 41176074, 51209048, 51409063）, High Tech Ship Research Project of Ministry of Industry and Technology （G014613002）, and the Support Plan for Youth Backbone Teachers of Harbin Engineering University （HEUCFQ 1408）
文摘The speed of a ship sailing in waves always slows down due to the decrease in efficiency of the propeller. So it is necessary and essential to analyze the unsteady hydrodynamic performance of propeller in waves. This paper is based on the numerical simulation and experimental research of hydrodynamics performance when the propeller is under wave conditions. Open-water propeller performance in calm water is calculated by commercial codes and the results are compared to experimental values to evaluate the accuracy of the numerical simulation method. The first-order Volume of Fluid(VOF) wave method in STAR CCM+ is utilized to simulate the three-dimensional numerical wave. According to the above prerequisite, the numerical calculation of hydrodynamic performance of the propeller under wave conditions is conducted, and the results reveal that both thrust and torque of the propeller under wave conditions reveal intense unsteady behavior. With the periodic variation of waves, ventilation, and even an effluent phenomenon appears on the propeller. Calculation results indicate, when ventilation or effluent appears, the numerical calculation model can capture the dynamic characteristics of the propeller accurately, thus providing a significant theory foundation forfurther studying the hydrodynamic performance of a propeller in waves.
文摘Electric propulsion is broadly defined as the acceleration of a working fluid for propulsion by electrical heating and/or by electric and magnetic body forces. Compared with chemical propulsion, electric propulsion has the characteristic of higher specific impulse, lower thrust, lighter weight and longer lifetime. So electric propulsion is generally suitable for satellite attitude control, the orbit transfer and raising, orbit correction, resistance compensate, position keeping, reposi- tion, space exploration and interplanetary flight.
