What are the types of industrial boiler burners? What are the common layout methods?

What are the types of industrial boiler burners? What are the common layout methods?
According to the appearance of the burner, it can be divided into two types: circular and slot type (groove type). According to the airflow conditions of the burner, it can be divided into two types: direct flow and swirl. Direct current burners are generally arranged at four corners, while swirl burners are often arranged on the front wall, front and rear walls, and both sides of the wall.