350MW超灵活锅炉深度调峰下水冷壁流动 不稳定性及动态特性分析

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中图分类号：TK223.3 文献标志码：A

Abstract： To address the typical hydrodynamic stability phenomena caused by rapid changes workg fluid parameters durg deep peak-shavg operation ultra-flexible boilers，a predictive model is proposed to deeply vestigate the density wave stability mechanism and dynamic response characteristics water walls. Based on the frequency doma method， the entire evaporator tube section is divided to three parts： subcooled，two-phase，and superheated regions. The conservation equations are learized and subjected to small perturbation treatment， and the transfer function the pipe section is obtaed by solvg with Laplace transform. Based on this process，a one-dimensional lear three-region critical heat flux prediction program is developed usg C language and MATLAB stware，and the Nyquist stability criterion is employed to evaluate system stability. Takg a 350MW ultra-flexible tower-type supercritical coal-fired boiler as the research object，the results show that at 75% and 30% rated loads，the critical heat flux values are 194.90kW/m2 and 26.38kW/m2 ，respectively，with actual operatg pots matag sufficient safety margs from the heat flux boundary. When the boiler operates between these two loads， creasg operatg pressure and heat flux enhances flow stability，while creasg tube length and reducg pipe clation angle reduce flow stability. Higher let enthalpy shortens the time required for the system to return to stability. This study provides a theoretical basis for the safe operation boilers durg deep peak-shavg.

words： deep peak regulation; density wave oscillation； dynamic characteristics; frequency doma method;Laplace transform

超灵活锅炉由于高效率、低排放、强调峰能力等优点，被广泛应用于电力生产中。（剩余14727字）