Recently, the use of renewable energies has increased to  environmental pollution, limitation of fossil energy resources and energy security  One of the means that enable us to use such energies is fuel cells (FC). However, there are many problems  in the commercialization of FC from an economically and operation perspective. One of the most important problems is heat management. New heat pipes...

A numerical technique is developed for the analysis of dissipative silencers of arbitrary, but axially uniform, cross section. Mean gas flow is included in a central airway that is separated from a bulk reacting porous material by a concentric perforate screen. The analysis begins by employing the finite element method to extract the eigenvalues and associated eigenvectors for a silencer of inf...

A transient, three-dimensional model for thermal transport in heat pipes and vapor chambers is developed. The Navier–Stokes equations along with the energy equation are solved numerically for the liquid and vapor flows. A porous medium formulation is used for the wick region. Evaporation and condensation at the liquid–vapor interface are modeled using kinetic theory. The influence of the wick m...

A transient, three-dimensional model for thermal transport in heat pipes and vapor chambers is developed. The Navier–Stokes equations along with the energy equation are solved numerically for the liquid and vapor flows. A porous medium formulation is used for the wick region. Evaporation and condensation at the liquid–vapor interface are modeled using kinetic theory. The influence of the wick m...

Free-reed organ pipes were introduced at the end of the 18 century and soon became popular across Europe, especially in Germany and Switzerland. As opposed to striking-reed pipes (boundor beating-reed pipes) the reed in free-reed pipes does not beat against the shallot, an orifice in the reed, when it is played. Instead it swings freely through a perforated rectangular plate of brass, like in r...

Buried pipes in the modern societies are considered as lifelines with a vital and essential role in the human life cycle. The performance of buried pipes is affected by many factors such as ground surface subsidence. In this paper, the effect of subsidence on pipelines is investigated using a three-dimensional numerical modeling developed in FLAC3D software for four types of most commonly used ...

In this article various pipes used for transporting of gas are introduced and pros and cons of each one are elucidated. The pipes are categorized in three different subgroups including metallic, polymeric and metallic-wire reinforced polymeric pipes. Metallic-wire reinforced polymeric pipes are nominated as the best option for usage in high pressure pipelines transporting natural gas. As a resu...