Browsing Institutt for energi og prosessteknikk by Title
Now showing items 2813-2832 of 4164
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On particle transport and turbulence in wellbore flows of non-Newtonian fluids - Findings from a cuttings transport process analysis by means of computational fluid dynamics, rheometry, and dimensional analysis
(Doctoral theses at NTNU;2020:95, Doctoral thesis, 2020)Cuttings transport modeling was analyzed with a major focus on three dimensional (3D) Computational Fluid Dynamics (CFD) approaches including rheometry and to a lesser extent on one-dimensional modeling and dimensional ... -
On solutions to equilibrium problems for systems of stiffened gases
(Journal article; Peer reviewed, 2011)We consider an isolated system of N immiscible fluids, each following a stiffened-gas equation of state. We consider the problem of calculating equilibrium states from the conserved fluid-mechanical properties, i.e., the ... -
On Soot Sampling: Considerations when Sampling for TEM Imaging and Differential Mobility Spectrometer
(Journal article; Peer reviewed, 2019)Particulate matter (PM) has been sampled from a compression ignition engine using a differential mobility spectrometer (Cambustion DMS 500) and for imaging in a transmission electron microscope (TEM) with the aim of coupling ... -
On the choice of closure complexity in anisotropic drag closures for filtered Two Fluid Models
(Peer reviewed; Journal article, 2019)Filtered Two Fluid Models (fTFMs) aim to enable accurate industrial-scale simulations of fluidized beds by means of closures accounting for the effects of bubbles and clusters. The present study aims to improve anisotropic ... -
On The Development of a Counter-Flow Mixing Reactor for Fast Hydrothermal Liquefaction
(Peer reviewed; Journal article, 2022)A laboratory-scale continuous tubular flow reactor system has been developed for fast HTL (hydrothermal liquefaction) of lignin, adopting the nozzle reactor concept with a counter-flow mixing design. The reactor is capable ... -
On the Effect of Boundary Conditions on the Flow around a Cylinder in a Channel
(Chapter, 2015)In this paper, the incompressible external flow around an offshore drilling riser with fairings at Reynolds number 5000 is used to study the effects of varying boundary conditions in numerical simulations. We use a direct ... -
On the effect of wicking on the droplet cooling
(Master thesis, 2018)Several thermal management applications operating at low temperatures require the liquid to spread as much as fast as possible in order to improve the cooling performance. Due to the recent progresses in micro/nano technology, ... -
On the exergy efficiency of CO<inf>2</inf> capture: The relation between sub-process and overall efficiencies
(Peer reviewed; Journal article, 2023)A generic exergy targeting tool for gas separation processes is developed, which is applicable to any defined boundary conditions for incoming feed gas as well as delivered separation products. Whereas targeting tools in ... -
On the financial balance of input–output constructs: revisiting an axiomatic evaluation
(Journal article; Peer reviewed, 2016-04-11)Financial balance is fundamental to input–output analysis (IO), andconsequently the respect of this balance is one of the dominant criteria inevaluating IO constructs. Kop Jansen and ten Raa (1990) proved that ... -
On the Motion of Inertial Particles in Unsteady Flows
(Doktoravhandlinger ved NTNU, 1503-8181; 2014:243, Doctoral thesis, 2014)Inertial particles transported in unsteady flows will not be able to follow the fluid motion perfectly. We explore some of the effects caused by particle inertia. The dissertation contains three parts. In the first part, ... -
On the occurrence of superimposed density wave oscillations on pressure drop oscillations and the influence of a compressible volume
(Journal article; Peer reviewed, 2018)Although two-phase flow instabilities are attributed to be one of the impediments for achieving high heat flux in boiling systems, most of their fundamental characteristics remain uncharted. In particular, pressure drop ... -
On the proper integration of wood stoves in passive houses under cold climates
(Journal article; Peer reviewed, 2014)The space-heating (SH) of residential buildings using a wood stove is an attractive solution. The way to properly integrate stoves in passive houses (PH) is still in question: current nominal powers are generally oversized ... -
On the proper integration of wood stoves in passive houses: investigation using detailed dynamic simulations
(Journal article; Peer reviewed, 2013)Wood stoves are attractive for the space-heating (SH) of passive houses. Nevertheless, there are still questions about their integration. Firstly, the power oversizing of the current stoves and their long operating time ... -
On the Relations between Lithium-Ion Battery Reaction Entropy, Surface Temperatures and Degradation
(Peer reviewed; Journal article, 2023)Understanding and mitigating the degradation of batteries is important for financial as well as environmental reasons. Many studies look at cell degradation in terms of capacity losses and the mechanisms causing them. ... -
On the role of symmetry and degeneracy in nonlinear thermoacoustic eigenproblems with application to can-annular combustors
(Doctoral theses at NTNU;2022:30, Doctoral thesis, 2022)The subject of this dissertation are thermoacoustic instabilities in combustion chambers with discrete rotational and reflective symmetries. Designing thermoacoustically stable combustors is one of the principal challenges ... -
On the Rotor Stator Interaction Effects of Low Specific Speed Francis Turbines
(Journal article; Peer reviewed, 2019)The rotor stator interaction in a low specific speed Francis model turbine and a pump-turbine is analyzed utilizing pressure sensors in the vaneless space and in the guide vane cascade. The measurements are analyzed relative ... -
On the Scalability of a Partially Premixed Low NOx Hydrogen Burner
(Doctoral theses at NTNU;2019:284, Doctoral thesis, 2019)Increasingly stringent regulations on nitric oxide (NOx) emissions led to the development of various low and ultra low NOx combustion technologies over the last decades. These technologies are further challenged by the ... -
On the scaling of convective boiling heat transfer coefficient
(Peer reviewed; Journal article, 2021)Flow boiling has been widely used during the last century, but the key mechanisms controlling the heat transfer process still remain elusive. In the particular case of convective flow boiling inside a heated pipe, most of ... -
On the structure of the near field of oxy-fuel jet flames using Raman/Rayleigh laser diagnostics
(Journal article; Peer reviewed, 2012)An experimental study on turbulent non-premixed jet flames is presented with focus on CO2-diluted oxy-fuel combustion using a coflow burner. Measurements of local temperatures and concentrations of the main species CO2, ... -
On the use of the water hammer equations with time dependent friction during a valve closure, for discharge estimation
(Peer reviewed; Journal article, 2016)The paper presents a new method for in site discharge estimation in pressured pipes. The method consists in using the water hammer equations solved with the method of characteristics with an unsteady friction factor model. ...