Study on Flow and Total Temperature Increase of Honeycomb Labyrinth Seals

The leakage flow and total temperature increase characteristics of a honeycomb labyrinth seal used in a typical gas turbine were numerically investigated and compared with a smooth labyrinth seal.The Reynolds-Averaged Navier-Stokes(RANS) equations and standard k-e turbulent model were adopted.The calculation of the leakage flow field and total temperature increase of two kinds of labyrinth seals with honeycomb stator and smooth stator were conducted at two kinds of leakage flow rates and different rotational speeds.The computed windage heating numbers of the honeycomb and smooth labyrinth seals agree well with the experimental data.The results show that the windage heating number of the honeycomb labyrinth seal is higher than that of the smooth one at the same leakage flow rate and rotational speed.The damping characteristics of the honeycomb cell enhance the windage heating number.The windage heating number increases with the increase of rotational speed and decreases with the increase of the leakage flow rate for the honeycomb and smooth labyrinth seals.For both the honeycomb labyrinth seal and smooth labyrinth seal,the increase of the leakage flow rate increases the meridional velocity at the same rotational speed,but the leakage flow fields of different leakage flow rate exhibit the similar flow pattern.