Search results for "OpenFOAM"
showing 6 items of 6 documents
Airflow and aerosol transport modeling with applications to Covid-19 aerosol reduction indoors
2022
Pēdējo pāris gadu laikā Covid-19 infekcijas slimība ir izraisījusi lielu kaitējumu cilvēkiem visā pasaulē, kas ir licis zinātniskajai kopienai apsvērt pieejas infekcijas mazināšanai, tostarp skaitliskās modelēšanas pieejas. Šī darba mērķis ir modelēt Covid-19 aerosola pārnesi un tā samazināšanu iekštelpās. Skaitliskās hidrodinamikas risināšanai tiek izmantota Reinoldsa vidējotā Navjē Stoksa modelēšanas pieeja kopā ar turbulentās difūzijas modeli aerosola pārnesei. Darbs sākas ar konkrētas telpas gaisa plūsmas modelēšanu un skaitlisko aprēķina parametru izpēti. Nākamajā daļā tiek izveidots gaisa attīrīšanas iekārtas matemātiskais modelis, kas tiek skaitliski ieviests un pārbaudīts izmantojot…
Torakālās aortas modeļa izveide no datortomogrāfijas uzņēmumiem un asins plūsmas modelēšana tajā
2019
Torakālās aortas aneirisma diagnosticēšanai izmanto vispārējus aortas parametrus, ar ku- riem nevar noteikt mazāk ekstrēmus, toties letālus, slimības izpausmes gadījumus. Darba mērķis ir izveidot modeli asins plūsmas aprēķinam torakālajā aortā izmantojot reālu pacientu datorto- mogrāfijas uzņēmumus un OpenFOAM atvērtā koda šķidrumu dinamikas rīkkopu. Darbā tika izveidots automātisks algoritms un izstrādāta metodika ģeometrijas apgabala un skaitliskā hidro- dinamikas režģa iegūšanai no aortas datortomogrāfijas uzņēmumiem. Izmantojot izveidoto režģi, tika veikta asins plūsmas modelēšana stacionārā un dinamiskā režīmā, piemeklējot piemērotākus robežnosacījumus pētāmajam apgabalam.
Experimental and Numerical Analysis of Air Flow, Heat Transfer and Thermal Comfort in Buildings with Different Heating Systems
2016
Abstract Monitoring of temperature, humidity and air flow velocity is performed in 5 experimental buildings with the inner size of 3×3×3 m3 located in Riga, Latvia. The buildings are equipped with different heating systems, such as an air-air heat pump, air-water heat pump, capillary heating mat on the ceiling and electric heater. Numerical simulation of air flow and heat transfer by convection, conduction and radiation is carried out using OpenFOAM software and compared with experimental data. Results are analysed regarding the temperature and air flow distribution as well as thermal comfort.
Contribution to the study of spray formation
2012
The work of this thesis aims to provide and validate tools useful to study and understand the phenomena involved in the injection of fuel, mainly focused on intra-flow injector. These tools are numeric and simulate the formation of a spray. A first part focuses on zero-dimensional modelling. Models which predict these following characteristics of spray like the spray angle, the spray penetration or the liquid length are compared with experimental data. The conclusions are that zero-dimensional modelling provides good results very quickly in some cases. Although, a better understanding of the influence of cavitation on the spray, which requires an understanding of the intra-flow injector, co…
Experimental study and numerical simulation of inclined rectangular weirs
2018
Inclined rectangular weirs, also named pivot weirs, are used both to adjust the upstream water level and to increase the flow capacity compared with that of normal rectangular weirs. However, the experimental studies available in the literature present contradictory conclusions for the inclined weir discharge capacity. In this paper, new experimental runs and numerical simulations were performed to investigate the effect of the rectangular weir inclination angle on the stage-discharge formula. The experiments were carried out using inclination angles ranging from 30° to 90°. Buckingham's theorem of dimensional analysis was used to obtain an equation for the flow magnification ratio (the dis…
Simulation of the Propagation of Tsunamis in Coastal Regions by a Two-Dimensional Non-Hydrostatic Shallow Water Solver
2017
Due to the enormous damages and losses of human lives in the inundated regions, the simulation of the propagation of tsunamis in coastal areas has received an increasing interest of the researchers. We present a 2D depth-integrated, non- hydrostatic shallow waters solver to simulate the propagation of tsunamis, solitary waves and surges in coastal regions. We write the governing continuity and momentum equations in conservative form and discretize the domain with unstructured triangular Generalized Delaunay meshes. We apply a fractional- time-step procedure, where two problems (steps) are consecutively solved. In the first and in the second step, we hypothesize a hydrostatic and a non-hydro…