scholarly journals The Effect of Hull Biofouling on Parameters Characterising Ship Propulsion System Efficiency

2015 ◽  
Vol 21 (4) ◽  
pp. 27-34X ◽  
Author(s):  
Wiesła Tarełko
Keyword(s):  
Rotational Speed ◽  
Operating Performance ◽  
Propulsion System ◽  
System Efficiency ◽  
Friction Resistance ◽  
Ship Propulsion ◽  
Different Types ◽  
Research Experiment

Abstract One of most important issues concerning technical objects is the increase of their operating performance. For a ship this performance mainly depends on the efficiency of its main pro-pulsion system and the resistance generated during its motion on water. The overall ship re-sistance, in turn, mainly depends on the hull friction resistance, closely related with the pres-ence of different types of roughness on the hull surface, including underwater part biofouling. The article analyses the effect of hull biofouling on selected parameters characterising the efficiency of the ship propulsion system with adjustable propeller. For this purpose a two-year research experiment was performed on a sailing vessel during its motor navigation phases. Based on the obtained results, three groups of characteristics were worked out for different combinations of engine rotational speed and adjustable propeller pitch settings. The obtained results have revealed that the phenomenon of underwater hull biofouling affects remarkably the parameters characterising propulsion system efficiency. In particular, the development of the biofouling layer leads to significant reduction of the speed of navigation.

scholarly journals Real-time Simulation of Ship Propulsion System

2004 ◽  
Vol 39 (12) ◽  
pp. 913-921
Author(s):  
Xianfu Hu ◽  
Hideaki Sugita ◽  
Takeshi Nakazawa ◽  
Yihuai Hu ◽  
Kengo Tanaka
Keyword(s):  
Real Time ◽  
Propulsion System ◽  
Real Time Simulation ◽  
Ship Propulsion ◽  
Time Simulation

scholarly journals Construction and performance analysis of data warehouse based on ship propulsion system

2021 ◽  
Vol 248 ◽  
pp. 01060
Author(s):  
Qi Hu ◽  
Yutao Chen ◽  
Yuqian He
Keyword(s):  
Data Warehouse ◽  
Visual Analysis ◽  
Hydrodynamic Characteristic ◽  
Propulsion System ◽  
Multidimensional Analysis ◽  
Hydrodynamic Characteristics ◽  
Soft Sensing ◽  
Ship Propulsion ◽  
System Data ◽  
And Performance

A large number of operation data will be generated in the process of ship propulsion system operation. Aiming at the processing, analysis and application of these operation data, a data warehouse for propulsion system is constructed based on the operation data of a ship, and the multidimensional analysis and result display of data are realized by combining OLAP technology with visual analysis software tableau. On the basis of the data warehouse, the soft sensing of parameters is applied to the data warehouse. Based on the soft sensing data, the hydrodynamic characteristics of the propeller are studied, and the hydrodynamic characteristic curves of the propeller are obtained. The research of ship propulsion system based on data warehouse provides support for the comprehensive information of propulsion system data.

scholarly journals Numerical Simulation on Hydraulic Characteristics of Nozzle in Waterjet Propulsion System

Processes ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 915 ◽  
Author(s):  
Chuan Wang ◽  
Xiaoke He ◽  
Li Cheng ◽  
Can Luo ◽  
Jing Xu ◽  
...  
Keyword(s):  
Propulsion System ◽  
Dynamics Simulation ◽  
Transition Curve ◽  
Hydraulic Loss ◽  
Main Function ◽  
System Efficiency ◽  
Hydraulic Characteristics ◽  
Linear Contraction ◽  
Circular Nozzle ◽  
Inlet Duct

As an important over-current component of the waterjet propulsion system, the main function of a nozzle is to transform the mechanical energy of the propulsion pump into the kinetic energy of the water and eject the water flow to obtain thrust. In this study, the nozzle with different geometry and parameters was simulated based on computational fluid dynamics simulation and experiment. Numerical results show a good agreement with experimental results. The results show that the nozzle with a circular shape outlet shrinks evenly. Under the designed flow rate condition, the velocity uniformity of the circular nozzle is 0.26% and 0.34% higher than that of the elliptical nozzle and the rounded rectangle nozzle, respectively. The pump efficiency of the circular nozzle is 0.31% and 0.14% higher than that of the others. The pressure recovery and hydraulic loss of the circular nozzle are superior. The hydraulic characteristics of the propulsion pump and waterjet propulsion system are optimal when the nozzle area is 30% times the outlet area of the inlet duct. Thus, the shaft power, head, thrust, and system efficiency of the propulsion pump and waterjet propulsion system are maximized. The system efficiency curve decreases rapidly when the outlet area exceeds 30% times the outlet area of the inlet duct. The transition curve forms greatly affect thrust and system efficiency. The transition of the linear contraction shows improved uniformity, and the hydraulic loss is reduced. Furthermore, the hydraulic performance of the nozzle with a linear contraction transition is better than that of others.

scholarly journals Development of an Android OS Based Controller of a Double Motor Propulsion System for Connected Electric Vehicles and Communication Delays Analysis

2015 ◽  
Vol 2015 ◽  
pp. 1-12
Author(s):  
Pedro Daniel Urbina Coronado ◽  
Horacio Ahuett-Garza ◽  
Vishnu-Baba Sundaresan ◽  
Ruben Morales-Menendez
Keyword(s):  
Rotational Speed ◽  
Wireless Local Area Network ◽  
Local Area Network ◽  
Autonomous Driving ◽  
Maximum Error ◽  
Local Area ◽  
Propulsion System ◽  
Area Network ◽  
Market Demand ◽  
Real Time Control

Developments of technologies that facilitate vehicle connectivity represent a market demand. In particular,mobile device(MD) technology provides advanced user interface, customization, and upgradability characteristics that can facilitate connectivity and possibly aid in the goal of autonomous driving. This work explores the use of a MD in the control system of a conceptualelectric vehicle(EV). While the use of MD for real-time control and monitoring has been reported, proper consideration has not been given to delays in data flow and their effects on system performance. The motor of a novel propulsion system for an EV was conditioned to be controlled in a wireless local area network by an ecosystem that includes a MD and an electronic board. An intended accelerator signal is predefined and sent to the motor and rotational speed values produced in the motor are sent back to the MD. Sample periods in which the communication really occurs are registered. Delays in the sample periods and produced errors in the accelerator and rotational speed signals are presented and analyzed. Maximum delays found in communications were of 0.2 s, while the maximum error produced in the accelerator signal was of 3.54%. Delays are also simulated, with a response that is similar to the behavior observed in the experiments.

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