Research Article

Study on Leakage Model of Typical Penetration of Closed Structures Based on Porous Media Seepage Theory

Table 3

Fitting of calculation formula for leakage rate of manhole pressure cover.

Initial sealing conditions F/kN100

Circumference of seal ring, B/m3.216

Surface composite roughness, σ/m3.2 × 10−6

Rubber material hardness, HA60

Kinematic viscosity of medium, μ/(Pa.s)Pressure P/MPa0.4511.52
Dry air1.80 × 10−51.80 × 10−51.80 × 10−51.80 × 10−5
Saturated steam8.00 × 10−55.90 × 10−55.30 × 10−54.69 × 10−5
Contact width, L/m0.023

Permeability, KRough flow factor, ΦσΦσ = exp (−0.9242 + 0.7026).
Height flow factor, ΦhΦh = exp (0.7545 − 3.673).
Dimensionless gap height, .
Dimensionless mean contact stress, .
Permeability, KK = ΦσΦh()3(h0)2/12.

The formula of leakage rate.