A Comparison of Experimental Rotordynamic Coefficients and Leakage Characteristics Between Hole-Pattern Gas Damper Seals and a Honeycomb Seal

Honeycomb annular seals are an attractive design alternative due to their superior static and dynamic performance. However, their implementation in industrial practice has been delayed by the following characteristics: a) manufacturing time can be appreciable, and b) they can seriously damage the shaft if rubbing occurs. To minimize these problems, “hole-pattern” gas damper seals, which are formed by simply drilling holes into an annular smooth seal, were manufactured and tested. The hole-pattern damper seal stator can be made of high-strength plastic materials which are less likely to damage a shaft during rubbing. The experimental results presented demonstrate that, compared to a honeycomb seal, a hole-pattern damper seal with 3.18 mm hole diameters and a high percentage of hole surface has achieved: (a) an average of 12 percent reduction in leakage rate, and (b) considerably higher effective damping, especially under high speeds and low inlet pressure ratio conditions.