The physical and mathematical model of temperature field for blast furnace stave coolers was established. The computation results show that the heat resistance of 2-6 mm water scale within the cooling pipe is about 7...The physical and mathematical model of temperature field for blast furnace stave coolers was established. The computation results show that the heat resistance of 2-6 mm water scale within the cooling pipe is about 7%-20% of the total heat resistance of cooling stave body, as for drilling duct type, the heat resistance of 2-6 mm water scale is about 88%-98% of the total heat resistance. Using drilling duct or full cast pipe can eliminate gas clearance and coating layer between pipes and cast iron body and reduce the heat resistance of the cooler sharply and improve the coefficient of heat transfer to a great extent. The water velocity within coolers can be kept at the 1evel of 0.5- 1 .5 m/s, the higher water velocity can not decrease the hot surface temperature, but can increase energy consumption for cooling water.展开更多
An experiment was carried out to investigate the relation of the maximum velocity of air passing through narrowest passage, mass flux of spray water in one square meter in one hour and the pressure drop of tube bundle...An experiment was carried out to investigate the relation of the maximum velocity of air passing through narrowest passage, mass flux of spray water in one square meter in one hour and the pressure drop of tube bundles. Twelve equations were obtained for the relation. The results show that the pressure drop of the tube bundles increases with increase of the maximum velocity of air and the mass flux of spray water. Comparing the pressure drop of the bare tube bundles with that of the film-enhanced tube bundles, it is found that the pressure drop of the film-enhanced tube bundles is lower about 11% and the surface roughness of the film-enhanced plates is a main factor that influences the pressure drop. The data and method obtained in the paper can be used to compute the pressure drop of the film-enhanced tube bundles and is helpful for selection of fan.展开更多
Cooling water systems(CWSs)are extensively utilized in various industries to eliminate the excess heat and converse energy.Studies on CWSs mainly concentrated on finding the optimal cooler network structure.In additio...Cooling water systems(CWSs)are extensively utilized in various industries to eliminate the excess heat and converse energy.Studies on CWSs mainly concentrated on finding the optimal cooler network structure.In addition,some works also considered the optimal design under varied operation conditions.However,in these works,once the optimal design of the cooler's network is determined,its arrangement remains fixed and cannot be adapted to accommodate diverse operating conditions.In this work,a flexible topology network concept is proposed to make the adjustment of network structure possible under different operation conditions.The CWS with integrated air cooler and flexible topology network has better overall performance,represented by a mixed integer nonlinear programming(MINLP)model that require advanced tools such as GAMS software.Case studies revealed that the proposed methodology can realize better energy-saving performance,and improve the economic performance under varied operation conditions.The impact of critical flexible nodes on system configuration and economy is achieved by sensitivity analysis.展开更多
文摘The physical and mathematical model of temperature field for blast furnace stave coolers was established. The computation results show that the heat resistance of 2-6 mm water scale within the cooling pipe is about 7%-20% of the total heat resistance of cooling stave body, as for drilling duct type, the heat resistance of 2-6 mm water scale is about 88%-98% of the total heat resistance. Using drilling duct or full cast pipe can eliminate gas clearance and coating layer between pipes and cast iron body and reduce the heat resistance of the cooler sharply and improve the coefficient of heat transfer to a great extent. The water velocity within coolers can be kept at the 1evel of 0.5- 1 .5 m/s, the higher water velocity can not decrease the hot surface temperature, but can increase energy consumption for cooling water.
基金Acknowledgement： The study is supported by the National Nature Science Foundation. Patent code is 200620098211.4.
文摘An experiment was carried out to investigate the relation of the maximum velocity of air passing through narrowest passage, mass flux of spray water in one square meter in one hour and the pressure drop of tube bundles. Twelve equations were obtained for the relation. The results show that the pressure drop of the tube bundles increases with increase of the maximum velocity of air and the mass flux of spray water. Comparing the pressure drop of the bare tube bundles with that of the film-enhanced tube bundles, it is found that the pressure drop of the film-enhanced tube bundles is lower about 11% and the surface roughness of the film-enhanced plates is a main factor that influences the pressure drop. The data and method obtained in the paper can be used to compute the pressure drop of the film-enhanced tube bundles and is helpful for selection of fan.
基金Financial support from the National Natural Science Foundation of China under Grant(Nos.22022816 and 22078358)
文摘Cooling water systems(CWSs)are extensively utilized in various industries to eliminate the excess heat and converse energy.Studies on CWSs mainly concentrated on finding the optimal cooler network structure.In addition,some works also considered the optimal design under varied operation conditions.However,in these works,once the optimal design of the cooler's network is determined,its arrangement remains fixed and cannot be adapted to accommodate diverse operating conditions.In this work,a flexible topology network concept is proposed to make the adjustment of network structure possible under different operation conditions.The CWS with integrated air cooler and flexible topology network has better overall performance,represented by a mixed integer nonlinear programming(MINLP)model that require advanced tools such as GAMS software.Case studies revealed that the proposed methodology can realize better energy-saving performance,and improve the economic performance under varied operation conditions.The impact of critical flexible nodes on system configuration and economy is achieved by sensitivity analysis.
文摘【目的】为了解决从空气中取水的高能耗和低效率问题,设计了一种利用热电制冷器(thermoelectric cooler,TEC)进行空气制水的装置。【方法】首先结合空气冷凝制水原理,利用TEC将散热翅片表面温度降低至露点温度以下;然后使装置与空气进行热量交换,从而实现空气中水蒸气的冷凝;最后考察了在不同输入电压和散热翅片面积下TEC的热力学参数对系统的能效比(coefficient of performance,COP)及比能耗的影响。【结果】当输入电压为4 V、热端循环冷却水流速为0.3 L/min、散热翅片面积为20320 mm 2时,空气制水器比能耗最低,为2135.27 kW·h/m 3,系统的最佳COP为2.7。相对于现有研究,本试验通过对空气制水装置输入电压和散热翅片面积等参数的优化,将从空气中制水的能耗有效降低了13.8%。【结论】本研究结果为降低空气制水过程中的高能耗和提高空气制水过程中的系统效率提供了一定的技术支持。
