Working of Velox Boiler

Working of Velox Boiler Points : Working of Velox Boiler Heat transfer rate is a lot higher in sonic velocity than to the subsonic velocity. Similar theory is utilized in design of Velox boiler in order to decrease surface area thus the size of evaporating tubes. Salient feature of Velox boiler is pressurized combustion. Air tense as of surroundings through axial flow compressor is dense up to 2.5 to 3 bar pressure. Compressed air at over sonic velocity and fuel are injected into vertical combustion chamber. The hot products of combustion at elevated velocity are passing into annulus of the concentric evaporating tubes. This hot gas transfer heat to feed water flow inside concentric evaporative tubes. Hot gases circulated on 10 to 20 times that of feed water flow. Wet steam produce in evaporative tubes is passing to steam separator in peripheral direction. It forms vortex in separator and due to centrifugal action humidity content of steam is separated. This separated water is pump back into feed water line. Dry steam divided is passed through the superheater tubes where it is superheated by the help of hot flue gases collect as of evaporating tubes. The hot gas discharge as of the superheater is extended in gas turbine. Power developed with the turbine is use to drive the compressor. Exhaust of gas turbine is use to heat the feed water in economizer before these are discharge to surroundings by the chimney.