بررسي و ارائه الگوي تاثير تزريق بخار به محفظه احتراق توربين هاي گازي به منظور افزايش راندمان

Investigating and Presenting the Effect of Steam Injection into Combustion Chamber of Gas Turbines to Increase Efficiency

ﻧﻘﺶ ﺗﻮرﺑﯿﻦ ﮔﺎز در ﻗﺮن ﻫﺴﺘﻪاي و ﺻﻨﻌﺘﯽ ﻓﻌﻠﯽ ﻧﺴﺒﺖ ﺑﻪ دﻫﻪﻫﺎي ﮔﺬﺷﺘﻪ ﺑﺴﯿﺎر ﻣﻮرد ﺗﻮﺟﻪ ﻗﺮار ﮔﺮﻓﺘﻪ اﺳﺖ. ﺑﻪ ﻣﻨﻈﻮر ﺑﻬﺒﻮد ﻋﻤﻠﮑﺮد ﺗﻮرﺑﯿﻦ ﮔﺎز روشﻫﺎي ﻣﺨﺘﻠﻔﯽ ﻧﻈﯿﺮ ﺑﺎزﯾﺎﺑﯽ، ﺧﻨﮏ ﮐﻨﻨﺪه واﺳﻂ دروﻧﯽ، ﭘﯿﺶ ﮔﺮﻣﺎﯾﺶ و ﺗﺰرﯾﻖ ﺑﺨﺎر آب اﺳﺘﻔﺎده ﺷﺪ اﺳﺖ. در اﯾﻦ ﺗﺤﻘﯿﻖ ﺗﺰرﯾﻖ ﺑﺨﺎر آب ﺑﻪ ﺟﺮﯾﺎن ﺑﺎﻻ دﺳﺖ ﻣﺤﻔﻈﻪ اﺣﺘﺮاق ﭘﯿﺸﻨﻬﺎد ﺷﺪه اﺳﺖ. در اﯾﻨﺠﺎ از ﮐﺪ ﻋﺪدي ﻧﺮماﻓﺰار ﺗﺠﺎري ﻓﻠﻮﺋﻨﺖ ﺑﺮاي ﺷﺒﯿﻪﺳﺎزي اﺣﺘﺮاق اﺳﺘﻔﺎده ﺷﺪه اﺳﺖ. ﺑﺮاي ﺷﺒﯿﻪﺳﺎزي اﺣﺘﺮاق ﺑﻪ ﯾﮏ ﻣﺪل اﺣﺘﺮاﻗﯽ ﻣﻨﺎﺳﺒﯽ ﻧﯿﺎز اﺳﺖ. ﻣﺪل ﻓﻠﯿﻤﻠﺖ ﺑﻪ دﻟﯿﻞ وﯾﮋﮔﯽﻫﺎي ﻣﺘﻌﺪد از ﺟﻤﻠﻪ ﺟﺪا ﮐﺮدن واﮐﻨﺶﻫﺎي ﺷﯿﻤﯿﺎﯾﯽ از ﻣﯿﺪام ﻣﻐﺸﻮش، ﯾﮑﯽ از ﭘﺮﮐﺎرﺑﺮدﺗﺮﯾﻦ ﻣﺪﻟﻬﺎي اراﺋﻪ ﺷﺪه در ﻣﻨﺎﺑﻊ اﺳﺖ. در اﯾﻦ ﭘﮋوﻫﺶ ﺷﻌﻠﻪ ﻣﺤﻔﻈﻪ اﺣﺘﺮاق ﺑﺎ اﺳﺘﻔﺎده از ﺳﯿﻨﺘﯿﮏ ﻣﮑﺎﻧﯿﺰم ﺷﯿﻤﯿﺎﯾﯽ DRM22 ﺑﺎ 22 ﮔﻮﻧﻪ ﺷﯿﻤﯿﺎﯾﯽ و 104 واﮐﻨﺶ ﻣﺪل ﺷﺪه اﺳﺖ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ دو ﻣﻨﻄﻘﮥ ﭼﺮﺧﺸﯽ در ﻣﺤﻔﻈﻪ اﺣﺘﺮاق اﯾﺠﺎد ﻣﯽﮔﺮدد. اﯾﻦ ﻣﻨﺎﻃﻖ ﻧﺸﺎن ﻣﯽدﻫﻨﺪ ﮐﻪ ﻣﯿﺪان ﺟﺮﯾﺎن درون ﻣﺤﻔﻈﻪ اﺣﺘﺮاق ﺑﺴﯿﺎر ﭘﯿﭽﯿﺪه ﻣﯽﺑﺎﺷﺪ. در ﻣﺤﻔﻈﻪ اﺣﺘﺮاق ﯾﮏ ورﺗﮑﺲ دروﻧﯽ در ﻃﻮل ﻣﺤﻮر ﻣﺮﮐﺰي و ﯾﮏ ورﺗﮑﺲ ﺑﯿﺮوﻧﯽ ﻧﺰدﯾﮏ ﻧﺎزل ﺗﺰرﯾﻖ ﺳﻮﺧﺖ ﺗﺎ دﯾﻮاره ﻣﺤﻔﻈﻪ اﺣﺘﺮق ﺗﺸﮑﯿﻞ ﻣﯽﮔﺮدد ﮐﻪ ﺑﺎ ﺗﺰرﯾﻖ ﺑﺨﺎر آب ورﺗﮑﺲ ﺳﻮم در ﻧﺎﺣﯿﮥ ﻧﺰدﯾﮏ ﺑﻪ ﻧﺎزل ﺑﺨﺎر آب ورودي ﺗﺸﮑﯿﻞ ﻣﯽﺷﻮد. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ ﺑﺎ ﺗﺰرﯾﻖ ﺑﺨﺎر آب دﻣﺎي درون ﻣﺤﻔﻈﻪ اﺣﺘﺮاق اﻧﺪﮐﯽ اﻓﺰاﯾﺶ ﺧﻮاﻫﺪ ﯾﺎﻓﺖ. اﯾﻦ ﭘﺪﯾﺪه ﺑﻪ اﯾﻦ ﻋﻠﺖ ﺗﺠﺰﯾﻪ ﻣﻮﻟﻮﮐﻮلﻫﺎي ﺑﺨﺎر آب ﺑﺪﻟﯿﻞ دﻣﺎي ﻓﻮق اﻟﻌﺎده ﺑﺎﻻي درون ﻣﺤﻔﻈﻪ اﺣﺘﺮاق ﻣﯽﺑﺎﺷﺪ. ﺑﻌﺪ از ﺗﺠﺰﯾﻪ، ﻫﯿﺪروژن ﺑﻪ ﻋﻨﻮان ﺳﻮﺧﺖ و اﮐﺴﯿﮋن ﻧﯿﺰ ﺑﻪ ﻋﻨﻮان اﮐﺴﺎﯾﻨﺪه وارد اﮐﻨﺶ ﺷﺪه و ﻣﻨﺠﺮ ﺑﻪ اﻓﺰاﯾﺶ دﻣﺎي ﺷﻌﻠﻪ و ﻋﻠﯽ اﻟﺨﺼﻮص دﻣﺎي ﻫﺴﺘﻪ ﻣﺮﮐﺰي ﺷﻌﻠﻊ ﻣﯽﺷﻮﻧﺪ. اﻣﺎ ﺑﺎ ﺗﺰرﯾﻖ ﺑﯿﺸﺘﺮ ﺑﺨﺎر آب رودي ﺗﺎ ﻧﺴﺒﺖ دﺑﯽ ﺟﺮﻣﯽ 0.2 ﻣﺸﺎﻫﺪه ﻣﯽﺷﻮد ﮐﻪ دﻣﺎي ﻫﺴﺘﻪ ﻣﺮﮐﺰي ﺷﻌﻠﻊ ﮐﺎﻫﺶ ﻣﯽﯾﺎﺑﺪ. ﺑﺎ ﺗﺰرﯾﻖ ﺑﺨﺎر آب از ﻧﺴﺒﺖ دﺑﯽ جرمي 0.05 تا 0.1 مشاهده مي شود كه كسر جرمي ناكس خروجي از محفظه احتراق افزايش خواهد يافت كه به دليل تجزيه مولوكول هاي بخار آب و افزايش دماي محفظه احتراق مي باشد. اما با افزايش بيشتر بخار آب ورودي، ناكس خروجي از محفظه به ﺷﺪت ﮐﺎﻫﺶ ﻣﯽﯾﺎﺑﺪ ﺑﻪ ﻃﻮري ﮐﻪ در ﻧﺴﺒﺖ دﺑﯽ ﺟﺮﻣﯽ 0.2 اﺧﺘﻼف ﻗﺎﺑﻞ ﻣﻼﺣﻈﻪاي ﻣﯿﺎن ﻧﺎﮐﺲ ﺧﺮوﺟﯽ در ﺣﺎﻟﺖ ﺑﺪون ﺗﺰرﯾﻖ ﺑﺨﺎر آب (mw/ma=0) و ﺣﺎﻟﺖ ﺗﺰرﯾﻖ ﺑﺨﺎر آب ((mw/ma=0.2) ﻣﺸﺎﻫﺪه ﺷﺪه اﺳﺖ.

The role of the gas turbine in the current century's nuclear and industrial sectors has been very much appreciated over the past decades. In order to Improvement of gas turbine function has been used for various methods such as recovery, internal cooling, preheating and water vapor injection. In this study, the injection of water vapor into the upper stream of the combustion chamber is proposed. Here is a numerical code for Fluent commercial software used to simulate combustion. An appropriate combustion model is required to simulate combustion. Felimelt's model is one of the most widely used models in the resources due to its numerous characteristics, including the separation of chemical reactions from the turbulent beam. In this study, the flame combustion chamber was modeled using the kinetics of the chemical mechanism DRM22 (with 22 chemical species and 104 reactions). The results showed that two rotary regions in the combustion chamber were created. These areas indicate that the flow field inside the combustion chamber is very complex. In the combustion chamber, an inner vortex along the central axis and an outer vortex close to the fuel injection nozzle is formed up to the wall of the combustion chamber, which is formed by injecting a third vortex water vapor in an area close to the inlet water nozzle. The results showed that with the injection of water vapor, the temperature inside the combustion chamber would increase slightly. This phenomenon is due to the decomposition of water vapor molecules due to the extremely high temperature inside the combustion chamber. After decomposition, hydrogen as a fuel and oxygen is also reacted as an oxidizer, resulting in increased flame temperature and, especially, the temperature of the core core of the mold. However, by injecting more inlet water vapor to a mass ratio of 0.2, it is observed that the core core temperature of the flame decreases. By injecting water vapor from a mass ratio of 0.05 to 0.1, the mass fraction of the Knox outlet from the combustion chamber will increase, due to the decomposition of the water vapor molecules and the increase of the combustion chamber temperature. However, with further increase in the inlet water vapor, Knox exits from the chamber sharply decreases so that in a mass ratio of 0.2, the significant difference between the output knox in the non-injecting mode of water vapor (m ̇_w / m ̇_a = 0) and The mode of water vapor injection (m ̇_w / m ̇_a = 0.2) has been observed.