energy transport

energy transport

The flow of heat from a hot to a cooler region by means of radiation, convection, or conduction. In stars the heat flows from the hot interior to the surface, where it is radiated away into space. The most important means of energy transport in most stars is radiative transport, in which high-energy photons lose energy to the hot plasma through scattering, mainly by free electrons, and by absorption through photoionization of ions; this occurs in the radiative zone of the star. (The equation of radiative transport is given at stellar structure.) Convection is another mode of energy transport in which collections of hot fluid in the convective zone of a star rise toward the surface, release their energy, and sink again to pick up more energy. Convection is a highly efficient process but the conditions must be right for its onset. Conduction is negligible in most stars but becomes important in very dense degenerate stars, such as white dwarfs.

The mode of energy transport has important effects on a star's evolution: radiation (and conduction) do not affect the shells of different composition within an evolved star, but convection mixes them to a uniform composition.

References in periodicals archive ?
President of Ukraine Petro Poroshenko had a meeting with leadership of STATNETT national energy transport company, the largest company on renewable energy in Europe STATCRAFT and the Norwegian Water Resources and Energy Directorate with participation of Minister of Petroleum and Energy of Norway Tord Lien.
Erdogan for his part announced that the two countries would seek to create an energy transport corridor to Europe in which Turkey would be the transit country.
Ofgem said energy transport costs have fallen 17% in 25 years.
TEHRAN (FNA)- An interdisciplinary group of researchers report on nanofibers, which enable for the first time a directed energy transport over several micrometers at room temperature.
The Guatemalan subsidiary of Grupo de Energia de Bogota, will use the funds to complete the project investing in energy transport, which is to build and launch more than 850 kilometers of transmission lines and 12 new high voltage substations, as well expansion of 12 existing substations.
In that context, he discusses an overview of the situation, strategic thinking on energy, energy exploration and utilization, energy transport and allocation, terminal energy consumption, the energy market, energy early warning and emergency response, innovation in energy technology, and ensuring energy sustainability.
Tokyo, Nov 28, 2012 - (JCN) - NYK Energy Transport (Atlantic) Ltd (NETA) celebrated its 10th anniversary at London's Natural History Museum on November 21.
20 November 2012 - Greece-based Seanergy Maritime Holdings Corp (NASDAQ:SHIP) said it had struck a deal to offload the 100% stake it owns in domestic marine transportation firm Bulk Energy Transport (Holdings) Ltd.
20 November 2012 a[euro]" Greece-based Seanergy Maritime Holdings Corp (NASDAQ:SHIP) said it had struck a deal to offload the 100% stake it owns in domestic marine transportation firm Bulk Energy Transport (Holdings) Ltd.
The Summit is appropriate for technical papers on topics concerning thermal management, heat transfer, electronics cooling and energy transport.
The EU27 failed to transpose into national law, by 2 March, the set of directives imposing a separation between energy production/supply activities and energy transport activities.
The 27 member states had until 2 March to transpose into their national laws the directives imposing a separation between energy production/supply activities and energy transport activities on their territory.

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