摘要当今社会，能源和环境问题不断干扰着人们的生活。随着经济的迅速发展，人们对能源的利用要求越来越高，在能源使用的同时要尽最大的可能减少对环境的影响。在当今的趋势下，天然气作为一种环保的能源得到了人们的不断重视。天然气作为一种对环境污染低的清洁能源，在人们生活的各个方面都得到了应用。但是由于天然气在液态的状态下的质量远远高于在气态的状态下，故天然气常常以液态的形式进行运输。87026

天然气作为车用燃料以液化的形式进行存储，而发动机在工作时需要天然气以气态的形式进行存储。为了能使LNG发动机可以利用液化天然气，LNG发动机里的天然气气化装置用发动机的冷却水对LNG进行气化。本文以潍柴WP7NG210E40天然气发动机为研究对象，根据其天然气的消耗量为其设计满足热量供给要求的气化装置。本文对该发动机设计了换热面积相同的直管式、U形管式、蛇形管式三种类型不同的气化装置结构。通过FLUENT软件对三种不同气化装置结构进行气化分析，在边界条件相等的情况下，U形管式气化装置气化效果最好。

毕业论文关键词：LNG；气化装置；水浴式；FLUENT

Abstract In today's society, energy and environmental problems constantly interfere with people's lives。With the rapid development of economy, people's demand for energy is higher and higher。 In the same time, it is possible to reduce the impact on the environment。In this trend, natural gas as a kind of environmental protection has been paid more and more attention to by people。 Natural gas, as a clean energy source, has been used in many aspects of people's lives。But because of the quality of natural gas in the liquid state is much higher than in the state of the gas, it is often in the form of liquid transport of natural gas。

Natural gas is stored as a vehicle fuel in the form of liquefaction, and the engine needs to be stored in the form of a gas when the engine is working。In order to make the LNG engine can use liquefied natural gas, LNG engine in the natural gas gasification unit with the engine's cooling water for LNG gasification。This paper to Weichai WP7NG210E40 natural gas engine as the research object, according to its natural gas consumption as the design meet the requirements of heat supply gasification device。This paper on the engine design the equal heat transfer area of straight tube, a U-shaped tube, coiled pipe type three different types of gasification device structure。Through the FLUENT software to analyze the structure of three kinds of different gasification device, in the case of equal boundary conditions, the U - shaped tubular gasification unit has the best effect on the gasification process。

Key words: LNG; Gasification plant;  Water -bath ; FLUENT

目  录

第一章 绪  论 1

1。1 研究背景 1

1。2 气化装置的研究现状与发展 2

1。3 LNG发动机用水浴式气化装置的现状与发展 3

1。4 本文的主要研究内容 3

第二章 水浴式气化装置的热计算 5

2。1 天然气发动机的选型 5

2。2 气化装置的热计算 6

2。2。1 热负荷的计算 6

2。2。2 平均温差的计算 7

2。2。3 总传热系数的计算 8

2。2。4 换热面积的计算 8

第三章 水浴式气化装置的结构设计