摘 要海水冷却系统作为主机冷却系统重要一环是保障主机正常运行的重要辅助系统。海水冷却系统通过海水外循环带走由淡水冷却系统带来的热量，通过降低淡水冷却水水温，从而避免了燃油燃烧产生的多余热量的累积造成主机温度过高，从而使得缸体及部件金属疲劳脆化以及润滑油的变质与失效。因此，海水冷却系统性能的优劣直接影响到船舶主机的工作性能，间接影响了整条船舶的性能好坏。因此，想要改善主机的工作环境，充分的发挥和优化船舶主机海水冷却系统的性能，就需要了解其工作过程中的动态过程，包括水力特性，和热力特性。计算机技术在仿真系统中的应用尤为广泛，MATLAB软件是当今最为流行的计算机建模仿真工具[1]。在MATLAB软件的仿真系统中，可以实现对海水冷却系统的模拟和跟踪研究。具有较好的研究意义。87033

本文基于12000HP油服船项目的海水冷却系统，以热力学和水力学的相关理论为基础，通过海水管路淡水管路的分析可以得到海水冷却系统的热力数学模型以及水力学数学模型。MATLAB中的SIMULINK工具可以根据数学模型建立仿真模块，将仿真所得出结果对比已知数据，检查仿真模型的正确性，从而可以在不同工况条件下仿真出海水冷却系统的工作状态。这就为今后在冷却系统的设计提供了一个较为方便的实验工具，对海水冷却系统的工作效能有了一个直观的比较。

当数学模型正确建立时，仿真模块合理准确的建立后，为了使整套系统具有可操作性和直观的交互界面，通过利用Access建立数据库作为仿真数据的中转站，将WebAccess与simulink模块连接起来，在WebAccess软件中设计出简洁美观的界面，用于读取仿真系统输出的数据即所需监测数据，以及切换按钮。最终达到对仿真的实时监测，以及通过对WebAccess的操作实现对仿真模块的控制。

毕业论文关键词：海水冷却系统；主机；低温淡水；建模；仿真； 

Abstract Salt water cooling system as an important part of cooling system of marine engine is an important auxiliary system which ensure the normal operation of the host very well。 Salt water cooling system through taking the excess heat from the fresh water cooling system。 Thus indirectly reduces the temperature of the host。 And it also can avoid some negative effect such as the metal fatigue and lube oil deterioration and failure which are caused by a large amount of heat accumulation。 So, the salt water cooling system performance are influences the performance of host performance directly。 So if we want to full develop the performance of ship host, understand the Heat & Hydraulics dynamic process of salt water cooling system is particularly important。 The computer simulation of MATLAB is one of the most popular tools at present。 When salt water cooling system of ship are simulated by MATLAB we can fully embodies the characteristics of tracking，researching and application of new technology, that have a great significance in research。

In this paper, we based on the salt water cooling system of Jiangsu University of Science and Technology 12000HP ship project。 Based on relative theory of fluid mechanics and heat transfer, and through the analysis of the system can get the mathematical model。 According to the mathematical we created, simulation modules can be established by SIMULINK。 By comparison with simulation results obtained from the known data, check the correctness of the simulation model。 Thereby the performance of salt water cooling system can be simulated in the different work condition by this model。 Which provided a convenient experiment tool for researchers who will design cooling system in the future。

When mathematical created correctly and simulation model reasonable established, use of Access and Webaccess a complete monitoring system can be established。 Due to the Webaccess can’t be connected directly, Access a software of office are act as an intermediary role which can receive data from a Simulink on the one hand, on the other hand can provide webaccess parameters。