Blar i Institutt for prosess-, energi- og miljøteknologi på forfatter "Bjerketvedt, Dag"
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An experimental investigation of rapid boiling of CO2
Tøsse, Sindre; Vågsæther, Knut; Bjerketvedt, Dag (Journal article; Peer reviewed, 2014-09-27)Storage of pressurized liquified gases is a growing safety concern in many industries. Knowledge of the thermodynamics and kinetics involved in the rapid depressurization and evaporation of such substances is key to the ... -
An experimental study of temperatures in cloud from release of flashing liquid CO2 in 3m long channel.
Adhikari, Amrit; Gaathaug, André Vagner; Bjerketvedt, Dag; Vågsæther, Knut (Journal article; Peer reviewed, 2014)Flashing of the liquid CO2 is an accidental hazards that may occurs in many industrial sector such as, process industries, carbon capture and storage projects, crude oil extraction process etc. Sometimes the accidental ... -
Boiling liquid expanding vapour explosion in CO2 small scale experiments
Bjerketvedt, Dag; Egeberg, Kjersti; Ke, Wei; Gaathaug, André Vagner; Vågsæther, Knut; Nilsen, Sandra Hennie (Journal article; Peer reviewed, 2011-04)Carbon capture and storage systems require handling large volumes of high pressure CO2. Having thorough knowledge of the related hazards is essential, as is knowing how to prevent, detect, control and mitigate accidents. ... -
Detonation propagation in stratified reactant layers
Gaathaug, André Vagner; Bjerketvedt, Dag; Lundberg, Joachim; Vågsæther, Knut (Journal article; Peer reviewed, 2017)A numerical investigation of detonation propagation in stratified reactant layers is presented in this paper. It is baesed on the reactive Euler equations using a two step chemical kinetics approach. The numerical simulations ... -
Effect of alternative fuel properties on NOx reduction
Axelsen, Ernst Petter; Tokheim, Lars-André; Bjerketvedt, Dag (Conference report, 2002)Today we see a substantial increase in the use of alternative fuels in the cement industry. The prospect of reduction in fuel costs and the environmental benefits of waste to energy conversion are the driving forces. For ... -
Energy recovery from wastes : experience with solid alternative fuels combustion in a precalciner cement kiln
Tokheim, Lars-André; Gautestad, Tor; Axelsen, Ernst Petter; Bjerketvedt, Dag (Conference report, 2001)Today virtually all cement clinker burning processes take place in rotary kilns. A mixture of calcareous and argilaceous materials is heated to a temperature of about 1450 °C. In this process decarbonation followed by ... -
Evaporation characteristics during decompression of liquified CO2 from a conical-shaped vessel
Ibrahim, Osama Kabbashi M.; Hansen, Per Morten; Bjerketvedt, Dag; Vågsæther, Knut (Peer reviewed; Journal article, 2021)Safe transport of pressurized CO2 requires a profound knowledge of the processes' effect during the phase transition on catastrophic failure of a tanker filled with liquid CO2. This study presents experimental results and ... -
Experimental Study of Gas Explosions in Hydrogen Sulfide-Natural Gas-Air Mixtures
Gaathaug, André Vagner; Bjerketvedt, Dag; Vågsæther, Knut; Nilsen, Sandra Hennie (Journal article; Peer reviewed, 2014-08-21)An experimental study of turbulent combustion of hydrogen sulfide (H2S) and natural gas was performed to provide reference data for verification of CFD codes and direct comparison. Hydrogen sulfide is present in most crude ... -
Experimental study of primary atomization characteristics of sonic air-assist atomizers
Sikka, Raghav; Vågsæther, Knut; Bjerketvedt, Dag; Lundberg, Joachim (Journal article; Peer reviewed, 2021)The present study compares two twin-fluid atomizer concepts based on the airflow (shock waves) pattern obtained through shadowgraph imaging for atomization of water with a low air/water pressure supply. The research work ... -
Experimental Study of the Initial Flame Propagation of Premixed H2-air Explosion in a Channel
Rai, Kanchan; Bjerketvedt, Dag; Sommersel, Ole Kristian (Conference object; Peer reviewed, 2009-07)This paper presents results from experiments on flame propagation in inhomogeneous and homogeneous hydrogen-air mixtures at 1 atm in a channel. The objective of the present work is to study the ininitial phase of the flame ... -
Experiments with flame propagation in a channel with one obstacle and premixed H2-air
Gaathaug, André Vagner; Bjerketvedt, Dag; Vågsæther, Knut (Conference object; Peer reviewed, 2009-07)This abstract presents experimental results of flame propagation in a square channel with a single obstacle. The background for the experimental study was to investigate how a flame propagated when and after the flame ... -
Explosion characteristics for Li-ion battery electrolytes at elevated temperatures
Henriksen, Mathias; Vågsæther, Knut; Lundberg, Joachim; Forseth, Sissel; Bjerketvedt, Dag (Peer reviewed; Journal article, 2019)Li-ion batteries are used in electronic devices and electric cars, yet they create safety concerns due to the possibility of the release of combustible materials. The electrolyte, one of the main components in a Li-ion ... -
Laminar burning velocity of the dimethyl carbonate–air mixture formed by the Li-ion electrolyte solvent
Henriksen, Mathias; Vågsæther, Knut; Gaathaug, Andre Vagner; Lundberg, Joachim; Forseth, Sissel; Bjerketvedt, Dag (Peer reviewed; Journal article, 2020)If a Li-ion cell fails and the electrolyte leaks out into air, a flammable premixed gas cloud can be formed. The electrolyte combustion energy is 65–70% of the total energy content of the cell. The main objective of this ... -
Modeling an image analysis of FAE
Vågsæther, Knut; Christensen, Svein Olav; Bjerketvedt, Dag (Conference lecture, 2008-09) -
Numerical study of premixed gas explosion in a 1-m channel partly filled with 18650 cell-like cylinders with experiments
Henriksen, Mathias; Vågsæther, Knut; Lundberg, Joachim; Forseth, Sissel; Bjerketvedt, Dag (Peer reviewed; Journal article, 2022)Abused and defective Li-ion cells can cause a catastrophic failure of a Li-ion battery (LIB), leading to severe fires and explosions. In recent years, several numerical and experimental studies have been conducted on the ... -
One-dimensional model of turbulent flow of non-Newtonian drilling mud in non-prismatic channels
Welahettige, Prasanna Kumara Welahetti; Lundberg, Joachim; Bjerketvedt, Dag; Lie, Bernt; Vågsæther, Knut (Peer reviewed; Journal article, 2019)One-dimensional model of non-Newtonian turbulent flow in a non-prismatic channel is challenging due to the difficulty of accurately accounting for flow properties in the 1-D model. In this study, we model the 1-D Saint–Venant ... -
Re-initiation of detonation across an inert region
Bjerketvedt, Dag (Doktor ingeniøravhandling;374, Doctoral thesis, 1985)Re-initiation of gaseous C-J detonation waves across a region of air has been studied experimentally. The experimental apparatus consisted of a 9 meter long square tube with internal dimensions of 125 mm. The Random Choice ... -
Release of liquid CO2 from the bottom of a duct
Mohammed Ibrahim, Osama Kabbashi; Gaathaug, Andre Vagner; Hansen, Per Morten; Bjerketvedt, Dag; Vågsæther, Knut (Peer reviewed; Journal article, 2023)This paper presents experimental results of the rapid phase transition of liquid CO2 released from the bottom of a small rectangular duct (BR). The aim is to consider the factors influencing the phase transitions and the ... -
Simulation of burning velocities in gases vented from thermal run-a-way lithium ion batteries
Johnsplass, Jonathan; Henriksen, Mathias; Vågsæther, Knut; Lundberg, Joachim; Bjerketvedt, Dag (Journal article; Peer reviewed, 2017)This paper describes the results from simulations of laminar burning velocities in the premixed air and flammable gases vented from abused Li-ion batteries. The released mixture from such batteries contain mixtures of ... -
Simulation of FA and DDT in a channel with repeated obstacles with an under-resolved mesh
Vågsæther, Knut; Bjerketvedt, Dag (Conference object; Peer reviewed, 2009)