Analysis Of The Two-Phase Flow Field In Rear Smoke Channel For Guiyang Power Station

Flow type of smoke fluid is turbulent gas-particle two-phase flow in rear smoke channel of power station boiler. There will appear a very uneven flow field, and appear a very big velocity magnitude distribution and ash concentration distribution near back wall. Thus, the velocity magnitude is far bigger than that of optimal design velocity magnitude, which will lead to serious wear and tear in metal face of heater. Especially, because of curve structure in front of heat pipe air preheater, there is more serious wear and tear.Because there would spend lots of time, money and labor force to experiment in boiler to estimate whether or not flow field is uniformity, using numerical simulation to solve practical problem is very easy and feasible.In this paper, we mainly use turbulent gas-particle two-phase flow model to simulate flow field of rear smoke channel. Firstly, simulate flow field of rear smoke channel, plot velocity magnitude and ash concentration distribution in section of entry of heat pipe air preheater, compare with data which were measured in Guiyang power station, verify simulation to be reasonable and right. Secondly, simulate all kinds of factors which affect flow field's uniformity such as length, thickness, location of diffluent board, ash concentration, ash diameter, and so on, find the chiefly factors. Thirdly, install guide board in curve channel in rear smoke channel, then simulate its' flow field, plot velocity magnitude and ash concentration distribution.In the paper, we try to use numerical simulation models to solve normal problem in engineering practice, so that saving labor force money and time. The result of simulation verifies the measure is very valuable.