太阳能热气流发电系统烟囱特性与辅助加热高度研究

Study on the Characteristics of the Auxiliary Heating Height in Solar Thermal Power Generation System

针对太阳能烟囱热气流发电系统,提出了对烟囱内气流进行二次辅助加热,以增大气体内能,加快气流速度,提高烟囱抽力的设想.采用数值模拟的方法,研究了辅助加热位置、加热温度、加热气量等因素对烟囱速度场、压力场分布的影响,并与无辅助加热情况进行了比较.结果表明,当辅助加热位置高度为45m,辅助加热气量与总气量比率为9%,加热气体温度为700K时,烟囱底部气流速度、负压是无辅助加热时的1.45倍和2.31倍.这说明二次辅助加热强化了烟囱的抽吸作用,有利于发电机组的正常连续运行和发电输出功率的提高.

The secondary auxiliary heating was proposed for solar chimney thermal power generation system,it could increase internal energy,velocity of air,chimney effect in the system.The methods of numerical simulation were adopted,the effects of velocity field and pressure field in the system were studied by some factors,which include auxiliary heating position,heating temperature,heating air flow,and so on.The condition was compared with no auxiliary heating conditions.The study showed that the air velocity under chimney was 1.45 times higher and negative pressure was 2.31 times higher than that without auxiliary heating,when the ratio of auxiliary heating gas and total air flow was 9% and the temperature of heating gas was 700 K.In the condition,chimney effect was improved,which make for continuous operation of generators and increase of power output power.