
2014年第7期(总第199期)
doi:10.3969/j. issn. 1009 3230. 2014. 07.008
应用能源技术
节流过程热力学特性及工程计算
宫克勤"?,施微,卢丽冰,李晓庆
(1.东北石油大学土木建筑工程学院,黑龙江大庆163318:
2.黑龙江省防灾减灾及防护工程重点实验室,黑龙江大庆163318)
摘要:分析节流过程中系统储存能与流动功之间的转换关系以及内位能变化对节流温度效应的影响,从能量转换与温度效应方面说明绝热节流与绝热膨胀过程之间的区别,给出实际流体节流的热力学性质计算方法,对过热水蒸气和未饱和水的绝热节流过程进行计算。计算结果表明:未饱和水节流气化相变导致过程的冷效应更加显著。
关键调:节流过程;热力学特性;储存能;温度效应;水蒸气中图分类号:TK0
)文献标志码:A文章编号:1009-3230(2014)07-0035-05
ThrottlingProcessThermodynamicProperties
and Engineering Calculation
GONG Ke - qin'-2, SHI Wei', LU Li bing', LI Xiao qing
(1.College of Civil and Architecture Engineering, Northeast Petroleum University; Daqing
35
Heilongjiang 163318; China; 2.Heilongjiang Key Laboratory of Disaster Prevention, Mitigatior
and Protection Engineering, Daqing Heilongjiang 163318; China)
Abstract:The throttling process transformation between storage energy and flow work as well as the impact of intemal potential upon temperature effect is analyzed in this paper, the difference between adiabatic expansion process and adiabatic throttle process is stated in the view of energy conversation and temperature effect, the calculating method of actual fluid throttling thermodynamic properties is provided. The adiabatic throttling process of superheated steam and unsaturated water are calculated. The result shows that the throttling temperature effects of unsaturated water is more pronounced due to the gasifying phase transitioning.
Key words:Throttling process; Themodynamic property; Storage energy; Temperature effect; Vapor
0引言
流体在管道内流经阅门、孔板等部位时,由于局部阻力的作用,使流体压力降低,这种现象称为节流现象,节流是工程上常见的过程。广义而言,节流过程就是节制流入或流出,通过增大流体阻力来减小流量的过程。因而节流过程不限于气收稿日期:20140515
修订日期:2014-0610
基金项目介:黑龙江省教育厅科技项目资助(项目号
12521048)
作者简介:宫克勤,男,主要研究油田建筑节能与教学。万方数据
体,对于液体而言,也存在节流现象。由于流体在管道内流动较快,通常散热量可以忽略,所以节流过程常常可简化为绝热节流过程来分析。
流体绝热节流过程与流体绝热膨胀过程是不同的。虽然两个过程都使得流体压力下降体积膨胀,并可以由此获得低温,但是两个过程有本质区别。节流过程流体降压原因是流体在流动过程中遇到阻力导致的,流体的可用能下降,是典型的不可逆过程;而绝热膨胀过程是流体通过体膨胀实