The interaction of work fluid mechanics with that of the rotary system itself, basically composed of axes, bearings and rotors, is performed by inserting equivalent dynamic coefficients in the mathematical model of the rotor, the latter being obtained by the finite element method. In this paper, the dynamic coefficients of inertia, stiffness and damping of the flat seals analyzed here are evalu...

Elastomeric seals are widely used to block fluids of high pressure. When multiple seals are installed in series and the spaces between the seals contain compressible fluids (e.g., gas or gas–liquid mixture), the seals often damage sequentially, one after another. Here, we demonstrate that the serial seals achieve high sealing capacity if individual seals undergo elastic leak, without material d...

It is necessary to obtain a fundamental understanding of the goaf gas flow patterns in longwall mine in order to develop optimum goaf gas drainage and spontaneous combustion (sponcom) management strategies. The best ventilation layout for a longwall underground mine should assist in goaf gas drainage and further reduce the risk of sponcom in the goaf. Further, in the longwall panel, regulators ...

An elastomeric seal may leak by elastic deformation without any material damage. We describe elastic leak using a theoretical model, and watch a seal deform and leak using a transparent experimental setup. The elastomer seals the fluid by forming contact with surroundinghardmaterials. As the fluid pressure increases, the contact stress also increases but not as much. When the fluid pressure sur...

Labyrinth seals are used in turbo-machinery for reducing the leakage of working fluid. The energy lost by the fluid passing through the gap between labyrinth seal and rotor causes the reduction in leakage rate. But the fluid in between the labyrinth seal and rotor induce various forces (radial and tangential forces). These forces can be represented by certain numbers of coefficients, such as st...

Abstract Interfacial surface roughness can result in fluid leakage of seals, and the design seals it is standard to give an upper limit for root-mean-square (rms) amplitude $$h_\text{rms}$$ h rms . However, determined mainly by long-wavelength roughness, which (ne...

Mechanical seals continue to be the predominant technology for shaft sealing in centrifugal pumps and other rotating equipment. While most mechanical seals are designed to operate on a liquid film, there are options for designing seal faces which function reliably while operating on a hydrodynamic gas film. In a dual pressurized seal (Arrangement 3), gas seals can provide unique benefits in ter...

A new hypothesis that pressure compartmentation in basins can be caused by capillary seals is presented and discussed. Capillary seals form when a non-wetting fluid phase is generated within or introduced into grain-size layered sediments that are finegrained enough that gravitational separation of the phases does not occur. Experiments show that such seals can be formed in the laboratory. Thes...