For over 15 years now, the efficiency and reliability of centrifugal compressors have been enhanced by the application of thermoplastic materials to the eye, shaft, and balance piston labyrinth seals. Traditionally these seals have been manufactured from metallic materials and have required relatively large clearances for reliability reasons. By upgrading to carefully selected engineered thermo...

A steady-state one-dimensional axisymmetric numerical model of a mechanical seal in two-phase flow is presented. In this work non-linear thermal implemented using coupled (monolithic) approach, linking the fluid film and sealing rings. It solved for temperature fields solids, heat fluxes between fluids enthalpy fluid, vapor mass fraction, Newtons method. The novelty approach lies 1) coupling 2)...

we define and studyco-noetherian dimension of rings for which the injective envelopeof simple modules have finite krull-dimension. this  is a moritainvariant dimension that measures how far the ring is from beingco-noetherian. the co-noetherian dimension of certain rings,including commutative rings, are determined. it is shown that the class ${mathcal w}_n$ of rings with co-noetherian dimension...

The reverse inter-shaft gas film seal is a path used in the intermediate bearing cavity of an aero-engine, which challenging to implement due its special installation and usage conditions. This paper proposes C/C (Carbon/Carbon) composite cylindrical structure carries out performance simulation analysis based on bidirectional fluid–solid coupling technology. results show that with double-layer ...

The end face-seals joint simultaneously the function of seal, bearing and heat exchanger. In order to improve the design of end-face seals the analysis of this type of joint by means of finite element method, was developed. The temperature distribution is indispensable to the analysis of displacement and stress in this type of face seal. In this work the values of temperature and stress in end-...

More than 10,000 Caspian seals (Phoca caspica) were reported dead in the Caspian Sea during spring and summer 2000. We performed necropsies and extensive laboratory analyses on 18 seals, as well as examination of the pattern of strandings and variation in weather in recent years, to identify the cause of mortality and potential contributory factors. The monthly stranding rate in 2000 was up to ...

Glacier Bay National Park had one of the largest breeding aggregations of harbor seals in Alaska, and it is functionally the only marine reserve for harbor seals in Alaska; yet, numbers of seals in the Bay are declining rapidly. Understanding why seals in Glacier Bay are declining may clarify their minimal habitat needs. We estimated population trends using models that controlled for environmen...

The purpose of this paper is to introduce some new classes of rings and modules that are closely related to the classes of almost Dedekind domains and almost Dedekind modules. We introduce the concepts of $\phi$-almost Dedekind rings and $\Phi$-almost Dedekind modules and study some properties of this classes. In this paper we get some equivalent conditions for $\phi$-almost Dedekind rings and ...

STOCK DEFINITION AND GEOGRAPHIC RANGE Spotted seals are distributed along the continental shelf of the Beaufort, Chukchi, Bering, and Okhotsk Seas south to the northern Yellow Sea and western Sea of Japan (Shaughnessy and Fay 1977, Fig. 11). Satellite tagging studies have provided considerable insight into the seasonal movements of spotted seals (Lowry et al. 1998, Lowry et al. 2000). Those stu...

Most competition studies between species are conducted from a population-level approach. Few studies have examined inter-specific competition in conjunction with intra-specific competition, with an individual-based approach. To our knowledge, none has been conducted on marine top predators. Sympatric Galapagos fur seals (Arctocephalus galapagoensis) and sea lions (Zalophus wollebaeki) share sim...