Thermodynamic Models and its Application for Open Feedwater Heaters under Transient Conditions

Abstract:

The aim of this paper is to find the energy distribution principle of open feedwater heaters under transient conditions. Taking a heater as the example and employing the first and second law of thermodynamics, thermodynamic models for vapor-liquid, mixture-liquid and liquid-liquid heaters were established and applied. And its energy distribution is obtained. The results indicate that that some error occurs when models for steady conditions are used at transient states. And the drain-cooler section has the largest error. The major factor is the exergy stored in exothermic fluid.

• Periodical: Advanced Materials Research (Volumes 516-517)
• Pages: 504-511
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.516-517.504
• Online since: May 2012
• Authors: Xi Yan Guo, Ai Juan Li, Hui Xu, Peng Fu
• Keywords: Energy Distribution, Surface Heaters, Thermodynamic Models, Transient Condition

References

[1] Shiying Ma, Ershu Xu, Xiaoduo Zhao．A Study of Dynamic Mathematical Model for Surface Heaters， 2001，3：30-32(in Chinese)

[2] Xiyan Guo．A Study on transient perfermance of a coal-fired power generating unit[B]. 2001，3

[3] Xingang Zhang, Zhigao Xu, Yong Li, Jianqun Xu．Numerical Analysis of the Dynamic Behavior of High-pressure Feed Water Heater of Fossil Power Sets[J]. Power Engineering， 2005，25(2)：262-268(in Chinese)

[4] Qishan He, Qing Huang, Hong Cai, Yuming Zhou．Numerical Value Calculation and Stress Analysis of the Temperature Differences Between the Tubes and Shells of Shell and Tube Heat Exchanges During Start-Up[J]. Chemical Engineering & Machinery，2004，31(3)：134-138 (in Chinese)

[5] Shuangying Wu; Yourong Li, Danling Zeng．Entropy Generation Analysis of Heat Transfer Process through a Duct[J]. Journal of Chongqing University(Natural Science Edition)，2001，24(2)：92~95 (in Chinese)

[6] Botao Yang, Dong-hong Qi． Thermoeconomic design of tubular heat exchanger[J]. ENGINEERING DESIGN，1998，2：46-48 (in Chinese)

[7] Xiaoliang Han, Liangzhi Han．Optimum Calculation of Heat Exchanger in Thermoeconomy [J]. Energy For Metallurgical Industry，1990,1:41-44 (in Chinese)

[8] Jimin Ma, Hongyong Wang, Shibing Geng, Xinghua Zhang．Exergy Calculation and Ex-I Figures of a Heat Exchanger[J]. Refrigeration & Air-condition，2002, 3: 5-8 (in Chinese)

[9] Jingyan Xing, Hai-qing Wang．Factors of affecting exergetic efficiency of heat exchanger and their functions in thermoeconomic analysis[J]. Journal of Shenyang Electric Power Institute，2003, 2:5-7 (in Chinese)

[10] Shuangying Wu, Yourong Li, Zejun Liu．The Analysis on the Effect of Cold and Heat Fluid Inlet Temperatures on the Thermodynamic Performance of Heat Exchanger[J]. Journal of Chongqing University，1999,2:69-74 (in Chinese)

[11] Fei Huang．Efficiency Analysis of Jet Heat Exchanger [J]. Energy for Metallurgical Industry，1999, 5:27-29 (in Chinese)

[12] Hua Zhu, Zhaoliang Wang, Chuanjing Tu．Thermodynamic analysis of heat pipe heat exchanger [J]. Journal of Zhejiang University(Engineering Science)， 1993, 4:465-471 (in Chinese)

[13] Weidao Shen, Zhimin Jiang, Jungeng Dong. Thermodynamics[M]. Beijing: . 2001：37，145

[14] Moran M J, Shapiro H N. Fundamentals of Engineering Thermodynamics.5th ed. New York: John Wiley & Sons, 2006：294.