毕业论文移动版

摘要目前在大型船舶舱室内，由于空间狭小、人群密度高，舱室内空气流动性差，空气污染严重。且现有船用空调装置中主要通过设置除尘过滤网和加大新风量来提高室内空气品质，较大的新风量会大大增加空调系统的造价和能耗，非常不利于船舶综合性能的发挥，舱室环境也已不能满足现代船舶人员的舒适性和健康性要求。所以如何通过改变通风方式改善舱室内气流组织，使得结果不仅能够降低整体空调通风系统的能耗，而且可以提高舱室内空气品质，将是未来船舶舱室空调通风系统设计的一个主要方向。86826

本文以某大型LNG动力船舶的典型舱室为研究对象。LNG动力船舶是将清洁能源液化天然气汽化后最为船舶动力，因LNG储量大、经济环保的特点，使用LNG作为远洋船舶动力已逐渐成为主流趋势。LNG汽化后会产生大量的冷能，本次研究的背景就是利用梯级汽化技术将LNG的汽化冷能用于船舶夏季冷负荷的空调通风系统。

本次研究运用雷诺平均法和零方程模型对所建立船舶典型舱室的物理模型的湍流流动进行分析论述。最终结果表明：送风方式是影响舱室内气流组织的重要因素，良好的气流组织能够极大改善舱室内的空气品质。相比于上送风，采用置换送风时能够形成比较好的气流组织，从而在速度场、温度场、热舒适度和空气品质方面都优于上送风。而同样最为混合送风的顶送风，最终形成了在温度场和空气品质方面都表现良好的气流组织，但是因为气流从上而下正对工作区域，热舒适性还需要改善。最后，本文通过对比分析，找出了适合于船舶舱室低矮空间下能够改善舱室内空气品质的通风形式，对指导相关船舶空调通风系统的设计具有参考价值和意义。

毕业论文关键词：LNG动力船；船舶舱室；气流组织；数值仿真；空气品质

Abstract At present, it has severe air pollution in large scale ship chamber due to small space, high crow density and bad air mobility。 Existed ship air-conditioner device sets dust extraction strainer and increases fresh air volume to improve room air quality, however, larger fresh air volume could make high cost and consumption of air-conditioner system, which is bad for ship comprehensive performance and for meeting comfort and healthy requirements of modern ship staff。 It is a main direction of air-conditioner ventilation system of ship chamber in future to change ventilation method to improve chamber air distribution, which could decrease energy consumption of whole air-conditioner ventilation system and improve chamber air quality。

A typical cabin in one large LNG powered ship is chosen for this paper。 LNG powdered ship is powered by LNG。 After vaporization, the clean energy of liquefied natural gas (LNG) can be used as ship’s power, and because it has large reserves, economic and environmental protection, using LNG as ocean ship’s power has gradually become the mainstream trend。 At the same time, the process of LNG vaporizing will produce large amount of colding capacity, the background of this sutudy is adopting cascade vaporization technology to make the cold energy meet the cooling load of air conditioning system in the ship。

This study applied Renault average method and zero equation model built a physical and mathematical model, and analyzed turbulent flow in this model。 It turns out that the way of air distribution has significant impacts on the cabin air distribution。 Good airflow organization can greatly improve the air quality inside the cabin。 Compared to the overhead (OH) system, underfloor air distribution (UFAD) has potential benefits such as better velocity field, temperature field, thermal comfortale and improved air quality。 And also top air supply eventually formed a good airflow organization in the temperature field and air quality。 But, because of the air flow, we need to improve it’s thermal comfort。 Finally, through the contrast analysis, this article find out the most suitable ventilation way for ship cabins, which will create a better environment for low space like ship cabins。 Last, the result has reference value and significance to guide the design of ship’s HVAC system。 (责任编辑：qin)