Sökning: "pebble"

Visar resultat 1 - 5 av 16 uppsatser innehållade ordet pebble.

  1. 1. How did Jupiter form?

    Kandidat-uppsats, Lunds universitet/Astronomi

    Författare :Calle Ahlgren; [2019]
    Nyckelord :Planet formation; Planet migration; Physics and Astronomy;

    Sammanfattning : Two relatively new concepts in planetary science are planetary migration; wherein the planets migrate through the protoplanetary disk as they form, and pebble accretion; wherein the planetesimals which become terrestrial planets and giant planet cores grow through the accretion of small pebbles. Planetary migration has become a generally accepted concept but there is still much to be learned even about how it affected the formation of our own solar system. LÄS MER

  2. 2. The fate of pebbles and planetesimals entering protoplanetary envelopes

    Master-uppsats, Lunds universitet/Astronomi

    Författare :Emil Zadera; [2019]
    Nyckelord :Planet formation; planet; protoplanet; protoplanetary envelope; protoplanetary atmosphere; protoplanetary growth; planetary growth model; accretion rate; vapour blob; vapourblob; vapour planet; transport of water; water on planet; pebbles; planetesimals; pebble accretion; planetesimal accretion; meteors; ablation; fragmentation; sublimation; protoplanetary disk; MMSN; accretion window; accretion channel; accretion; destruction; disruption; terminal velocity; gas; gasflow; shearingbox; exoplanet; Physics and Astronomy;

    Sammanfattning : Planetary embryos grow by the accretion of solid dust-material, ranging from cm- to m-sized pebbles up to km-sized planetesimals. However, the underlying size-distribution of the accreted material is poorly understood. LÄS MER

  3. 3. Formation and Evolution of Protoplanetary Disks

    Master-uppsats, Lunds universitet/Astronomi

    Författare :Johan Appelgren; [2019]
    Nyckelord :protoplanetary disk; protoplanetary disk formation; protoplanetary disk evolution; planet formation; Physics and Astronomy;

    Sammanfattning : A star forms with a surrounding protoplanetary disk after the collapse of a molecular cloud core. Subsequently, over a period of several Myr this protoplanetary disk of dust and gas is accreted onto the host star. We model the formation and evolution of such a protoplanetary disk using a one-dimensional numerical model. LÄS MER

  4. 4. Numerical Analysis of Local Flow and Heat Transfer Characteristic in a Regular Arranged Pebble Bed Reactor

    Master-uppsats, KTH/Fysik

    Författare :Bai Yuyu; [2018]
    Nyckelord :;

    Sammanfattning : .... LÄS MER

  5. 5. Överraskningens orsaker : En flerfallsstudie om vad som orsakar överraskning på taktisk beslutsnivå

    Uppsats för yrkesexamina på grundnivå, Försvarshögskolan

    Författare :Fredrik Jönsson; [2018]
    Nyckelord :Överraskning; taktik; taktisk beslutsnivå; specialoperationer; Pebble Island; Operation Biting;

    Sammanfattning : Military theories regarding surprise has a conceptual way of being described which may influence the effect that surprise actually has on a specific command level. Without sufficient explanations there might be unclear reasons for the conversion of these theories into practice. LÄS MER