| The endwall is one important part of the gas turbine. It has a hostile work environment with high temperature. So enough protection on the endwall is with gjreat significant, there are complicate secondary flow on the endwall. So the endwall film cooling is difficult to carry out. The cooling film effected by the vortex on the endwall and the transverse pressure gradient can not be attached to endwall easily. So the endwall need effective cooling scheme and the effective means to control the endwall secondary flow.In this paper, through numerical simulation method to Research theme.Mainly involves two most of the research. The first is to a certain type of gas turbine blade cooling scheme for numerical simulation. Get the existing problems and to recommend it, And then according to the calculated results do the design by progressive type. The jet Angle of a row of holes and the axial location are discussed. Finally the position is set 33mm before the blade. The jet angle is 300°into the axial. In this paper,Gradually progressive cooling from a row of hole to get four hole cooling scheme. Compared the three blow ratios, and the different arrangement of four hole cooling effect, when the blowing ratio is 2.0 cooling gas film covering is the best,Arranged along the isobar cooling air extensibility is best. Arranged along the axial arrangement of cooling gas film distribution. Finally through to the four hole cooling solutions for local refinement to get ideal endwall cooling scheme.By another part of the article mainly discussed two kinds of way’s influence how to control the endwall secondary flow. Nonaxisymmetric Endwall shape and root fillet. The article in order to ensure the smoothness of modelling using high trigonometric function as the end wall shape control function. And by changing the phase angle and amplitude control function to control the shape of end wall, Compare the changes in the Angle of all sorts of modelling in the phase compensation of flow characteristics of change. And the influence of the one row hole endwall cooling. Compare the control function of amplitude change change range of modelling of end wall, Observe the modelling function amplitude change of flow characteristics and the influence of side wall cooling effect. Also the change of the amplitude of control function. With the change of the radius of the root fillet of the blade. Observe the modelling function amplitude change of flow characteristics and the influence of side wall cooling effect. Through the study found that in a hole when the Angle is 90 phase compensation overall cooling effect is best. The highest cooling efficiency is 0.3213, And the blind cooling gas film covering area is minimal. With the increase of amplitude, modelling of endwall increased, the overall cooling efficiency is increased from 0.2876 to 0.3213, but the blind partial cooling increased. Along with the rising of the chamfering radius, radial displacement of the bottom position of the vortex system, and thus change the cooling effect of end wall. As with chamfer of blade root, and with the chamfering radius increased from 1 mm to 6 mm. Overall average cooling efficiency is increased from 0.2688 to 0.3075, the cooling effect is improved. |
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