Experimental and Numerical Analysis of the Gas Flow in the Axisymmetric Radial Clearance

2021

E3S Web Conf.

Self Cite

In this paper a method for reducing leakage in labyrinth seals is presented. This method is based on CFD calculations and consists in the analysis of the phenomenon of gas kinetic energy carry-over in chambers of the seal between gaps. It belongs to the group of geometrical inverse problems and is designed for seals of given outside dimensions. For straight through labyrinth seals it enables determining the number of teeth and their optimal arrangement. This method was developed based on numerical and experimental tests. Examples of numerical calculations presented in this paper prove that this method is effective for straight through seals. We obtained the reduction of leakage ranging from 8.7 to 9.4% relative to the initial geometry with no change in the outside dimensions of the seal.

Section: Fig 3 Vectors Of Velocity Fields In a Chosen Segmentmentioning

confidence: 99%

Method for the reduction of leakage in labyrinth seals by adapting the seal geometry to match the flow conditions

2021

E3S Web Conf.

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“…The degree of sealing wear and tear has a considerable impact on the failure of the seal integrity [21][22][23]. Slight changes in the dimensions of the clearance influence the leakage value and the flow coefficients, which is presented in the paper [24]. A seal with staggered helical teeth, which is characterized by reduced leakage, is presented in the paper [25].…”

Section: Introductionmentioning

confidence: 99%

Novel Method of the Seal Aerodynamic Design to Reduce Leakage by Matching the Seal Geometry to Flow Conditions

2021

Energies

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This paper presents a novel method of labyrinth seals design. This method is based on CFD calculations and consists in the analysis of the phenomenon of gas kinetic energy carry-over in the seal chambers between clearances. The design method is presented in two variants. The first variant is designed for seals for which it is impossible to change their external dimensions (length and height). The second variant enables designing the seal geometry without changing the seal length and with a slight change of the seal height. Apart from the optimal distribution of teeth, this variant provides for adjusting chambers geometry to flow conditions. As the result of using both variants such design of the seal geometry with respect to leakage is obtained which enables achieving kinetic energy dissipation as uniform as possible in each chamber of the seal. The method was developed based on numerical calculations and the analysis of the flow phenomena. Calculation examples included in this paper show that the obtained reduction of leakage for the first variant ranges from 3.4% to 15.5%, when compared with the initial geometry. The relation between the number of seal teeth and the leakage rate is also analyzed here. The second variant allows for reduction of leakage rate by 15.4%, when compared with the geometry with the same number of teeth. It is shown that the newly designed geometry reveals almost stable relative reduction of leakage rate irrespective of the pressure ratio upstream and downstream the seal. The efficiency of the used method is proved for various heights of the seal clearance.

“…Research work comprises the analysis of thermo-dynamic and flow phenomena occurring in seals of that type. The influence of the dimensions of clearance on the leakage value was analyzed in [9]. In papers [10,11] the optimal choice of the geometry of the straight through seal to minimize the leakage was investigated.…”

Section: Introductionmentioning

confidence: 99%

Analysis of the impact of the labyrinth seal geometric parameters on the leakage

Krzyślak

2021

E3S Web Conf.

Self Cite

This paper includes results of experimental research and CFD calculations concerning gas flow in segments of straight through labyrinth seals of fixed length and varying number of teeth. Relation between the number of teeth and the leakage is analyzed in this paper. Authors determined the range of teeth number for which the minimum leakage was achieved. They focused particularly on the analysis of geometry with maximum number of teeth which fell within the range of the minimum leakage. For this geometry they examined the relation between the thickness of the teeth and the distribution of gas pressure and velocity along the seal and the leakage size. Data presented in this paper indicate that the teeth thickness has a significant impact on the flow parameters.