TUIT väljaanded ja artiklid

Permanent URI for this collectionhttps://hdl.handle.net/10062/62579

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    Development and computational fluid dynamics (CFD) simulation of cryostat thermal shielding for a portable high purity germanium (HPGe) gamma spectrometer
    (Taylor&Francis, 2020) Malgin, Vladislav; Tkaczyk, Alan H.; Yakovlev, Oleg; Jeltsov, Marti; Priimägi, Priit
    The effect of vacuum degradation in cryostat of a gamma spectrometer on the steady-state temperature of thermal shield and its efficiency are analyzed in this study. Considering the thermal load due to radiation, the thermal conductivity of residual gases and shield supports, the steady-state temperature of the shield is determined based on the differential energy balance equation for a simplified thermal model of the cryostat. A more complex model corresponding to the design of a real cryostat is simulated using computational fluid dynamics. The obtained temperature distribution is presented. The simulated results are compared with experimental data measured on an operating cryostat with a cryocooler in the temperature stabilization mode. The same measurements were carried out for a cryostat with and without a thermal shield, as well as with multilayer insulation. The obtained results confirm that the thermal shield provides decreasing heat transfer even for a vacuum degradation in a cryostat
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    Development and validation of a CFD-enabled digital twin of a portable HPGe gamma spectrometer
    (IOP Publishing, 2020-01-22) Jeltsov, Marti; Priimägi, Priit; Malgin, Vladislav; Takovlev, Oleg; Tkaczyk, Alan H.
    This paper presents the design of an easily portable spectrometer using high purity germanium (HPGe) detector – HandSpec. The key challenge in the design of a lightweight spectrometer is to minimize its heat losses so that efficient electric cooling could be used instead of bulky dewars. The design process has been largely based on experimental investigations. In this study, a digital twin of the HandSpec cryostat using computational fluid dynamics (CFD) method is developed to support the design and optimization of the physical prototype.
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    Tark Laut. Taastuvenergial töötava termoreguleeritud lauda kontseptsioon-lahenduse loomine.
    (2018) Olonen, Tõnno toim.
    Projekti käigus loodi Koivakonnu mahe lihaveisefarmi ja Tartu Ülikooli koostööl innovatiivne taastuvenergial töötav energiatõhus termoreguleeritud veiselauda kontseptsioon-lahendus (TARK LAUT). TARK LAUT on lihaveiste pidamiseks optimaalse mikrokliimaga ehitus-tehniline lahendus, mis suurendab loomade heaolu päevavalguse parema kasutamisega, muudab allapanu vahetamise / sõnnikukäitlemise mugavamaks nii loomadele kui loomapidajatele ning suurendab loomade metaboliseeruva energia kasutuse efektiivsust läbi optimaalse temperatuuri ning õhuringluse. Hoone kasutab maksimaalselt ära päikeseenergiat ning aastaringne sisetemperatuur plusskraadides on tagatud minimaalse lisaküttevajadusega. Kontseptsioonlahendus võimaldab veisekasvatajatel kasutada hoonet suvel kõrge lisandväärtusega kõrvalsaaduste kasvatamiseks ja/või kuiva heina tootmiseks