Ventilation Design and Numerical Simulation of Diesel Engine Room

• Main Authors: LIU, YAO-FU, 劉耀復
• Other Authors: HSU, CHEUNG-HWA
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/k59762

碩士 === 國立高雄科技大學 === 模具工程系 === 107 === Engine room can be seen as the heart of a ship. Since it accommodates numbers of machines, the amount of transfer heat is remarkable. In order to boost the working efficiency, a ventilation system is used to provide the main engines, generators and other auxiliary equipment with endless fresh air, which then pushes transfer heat out from the room. The design of ventilation system in engine room starts from contract design phase. Primary action items include calculation of ventilation, specification selection and piping displacement. Most domestic shipyards now adopt tradition method with accumulated experience to design ventilation system for engine room. The significant problem of existing method lies in the evaluation of ventilation system only can be known when the construction phase is finished. If the effectiveness could not meet the requirement, the ship performance will be influenced. When the situation gets even worse, the ship has to be refined in shipyard, which results in delay of the following schedule. CFD numerical simulation technique can be used to estimate the temperature distribution of engine room. In pursuit of appropriate air flow field for ventilation design and prevention from reworking in construction phase, the simulated result then is exploited as a basis to modify the ventilation allocation as well as the location. On one side, the work concentrates on design of ventilation system for transport ship, which takes design requirement, calculation of ventilation, specification selection of ventilator, setting of ventilator outlet, pipe diameter and other relating factors into consideration. A standard of design procedure is built to improve the reliability and accuracy for ventilation system in engine room. On the other side, the CFD numerical simulation software named FLUENT is implemented to check and analyze whether the ventilation design meets the need. Compared with the ventilation system designed by traditional method, the result shows that the one went through advanced standard design procedure has better effectiveness, which means forming a greater air flow field and lowing the temperature significantly. Keywords：Marine engine room；Diesel engine；Ventilation system；CFD；Numerical simulation analysis.