• A CFD Study of Preventing Snow Accumulations on Roofs using Airflows 

      Sjøveian, Andreas; Andleeb, Zahra; Khawaja, Hassan Abbas; Moatamedi, Mojtaba (Conference object; Konferansebidrag, 2023-12)
      Today, there is an abundance of roof designs for buildings, each possessing distinct characteristics when subjected to snowy and cold conditions. Snow buildup on roofs poses various risks, including structural damage and personal injuries. Snow loads can lead to severe building damage or even collapse. The presence of intricate roof shapes and valleys exacerbates the potential harm caused by snow. ...
    • Conjugate Heat Transfer Model Based on SIMPLE and Coupled Energy and Heat Equations 

      Leyli, Amir Nadem; Andleeb, Zahra; Khawaja, Hassan; Messahel, Ramzi; Kanna, Rajesh; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-01-28)
      In this study, a numerical weak coupling strategy for the modeling of a conjugate heat transfer phenomenon is considered. Where the incompressible Navier-Stokes equations are solved using the Semi-Implicit Method for Pressure Linked Equations (SIMPLE) as a first step, and then the heat conduction equation for solid is solved in a second step considering the convective velocity field resulting from ...
    • Data Processing Scheme for Laser Spot Thermography Applied for Nondestructive Testing of Composite Laminates 

      Roemer, Jakub; Khawaja, Hassan; Moatamedi, Mojtaba; Pieczonka, Lukasz (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-08)
      This paper proposes a data processing scheme for laser spot thermography (LST) applied for nondestructive testing (NDT) of composite laminates. The LST involves recording multiple thermographic sequences, resulting in large amounts of data that have to be processed cumulatively to evaluate the diagnostic information. This paper demonstrates a new data processing scheme based on parameterization and ...
    • Determining Thermal Properties of Polyurethane by Solving the Heat Equation and IR Imaging 

      Eidesen, Hans-Kristian; Andleeb, Zahra; Khawaja, Hassan; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-06-27)
      All materials have different and unique thermal properties that determine how the temperature changes when a material is subjected to a temperature difference. This study was intended to investigate the thermal properties of a polymer called Polyurethane, focusing on anti-seepage and anti-abrasion polyurethane. The thermal conductivity and heat transfer coefficient of cold polyurethane specimens ...
    • Finite Element Analysis to determine the impact of Infill density on Mechanical Properties of 3D Printed Materials 

      Andleeb, Zahra; Khawaja, Hassan; Andersen, Kristian; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-29)
      Additive manufacturing (AM) is the process in which objects are created through the layer-by-layer deposition of material that is controlled by a computer. The infill is the internal structure of the 3D printed model. It determines the strength, weight, cost, time, and overall quality of the part. Ranging from simple lines to more complex geometric shapes, infill patterns can affect a part's ...
    • Fluid solid interaction simulation of CFRP shell structure 

      Khawaja, Hassan Abbas; Messahel, Ramzi; Souli, Mhmed; Al-Bahkali, Essam; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2017)
      This work attempts to model the dynamic behavior of Carbon Fiber Reinforced Polymer (CFRP) shell structure subjected to water shock wave to improve the results presented in the study by Khawaja et al., 2014. In the previous study, the real physical problem was simplified by decoupling the fluid and the structural phenomena, applying the recorded experimental fluid pressure load to the CFRP shell ...
    • Ice shedding from wind turbines 

      Khawaja, Hassan Abbas; Xue, Hui; Eidesen, Hans-Kristian; Andleeb, Zahra; Moatamedi, Mojtaba (Chapter; Bokkapittel, 2024)
      Wind power is an excellent source of renewable energy in areas with sufficient wind resources. Usually, the best locations for wind turbines are on the tops of hills and ridges, where there are lower temperatures [1]. Cold temperatures are responsible for novel challenges [2, 3]. Due to cold climatic conditions, turbine blades are subjected to icing [4]. A number of methods have been proposed and ...
    • Infrared Thermography (IRT) of Conjugate Heat Transfer (CHT) Problem and Comparison with Multiphysics Model 

      Khawaja, Hassan; Moatamedi, Mojtaba; Alzahabi, Basem (Conference object; Konferansebidrag, 2018)
      This work presents a problem undergoing conjugate heat transfer (CHT). Conjugate heat transfer problems are common is domestic heating/cooling, industrial heat exchangers, cooling of electronics (e.g. PC fans). It is to be noted that in conjugate heat transfer problems, the convection part of the heat transfer is dominated. In the given study, a hypothetical case is built where a heat source (a ...
    • Investigation of Composite Mechanical Properties from Additive Manufacturing 

      Andleeb, Zahra; Khawaja, Hassan; Andersen, Kristian G; Edvardsen, Kåre; Moatamedi, Mojtaba (Conference object; Konferansebidrag, 2022)
      Manufacturers consider carbon fiber as a wonder material for the world's economy. Its distinctive combination of high strength and low weight has helped drive the wind power revolution and make aircraft and ships more fuel-efficient. In addition, the carbon fiber structures can function longer and are more rigid than the traditional metallic models, making them more resilient in cold and more efficient ...
    • Is Thorium a Viable Nuclear Fuel? [poster] 

      Khawaja, Hassan; Moatamedi, Mojtaba; Tehrani, Ali (Conference object; Konferansebidrag, 2018)
      Thorium was discovered in 1829 by the Norwegian mineralogist Morten Thrane Esmark and identified by the Swedish chemist Jöns Jacob Berzelius, who named it after Thor, the Norse god of thunder. Thorium is more abundant in nature than Uranium. It is fertile rather than fissile, and can only be used as a fuel in conjunction with a fissile material such as recycled plutonium. Thorium fuels can breed ...
    • Modeling of Pressure and Temperature Profiles for the Flow of CO2 through a Restriction 

      Leyli, Amir Nadem; Jackson, Steven; Khawaja, Hassan; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-19)
      CO<sub>2</sub> emissions due to massive industrialization have led to several environmental issues. Carbon Capture and Storage (CCS) is one of the most important technologies that can be used to reduce anthropogenic CO<sub>2</sub> emissions worldwide. CCS projects mainly involve three processes: carbon capture, transportation, and storage. In the transportation process, the modeling of the flow in ...
    • Multiphysics Analysis of CFRP Charpy Tests by varying Temperatures 

      Andleeb, Zahra; Strand, Cathrine Høgmo; Malik, Sohail; Hussain, G; Khawaja, Hassan; Boiger, Gernot; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2020)
      Carbon Fiber Reinforced Polymer (CFRP) composites have emerged as a major class of structural materials that have a significant potential use as a substitute for metals in aerospace, marine, automotive, and architecture due to their higher-strength-to-weight-ratio. CFRP is well suited for various applications, but their mechanical properties such as ‘low-velocity impact resistance’ are not well ...
    • Multiphysics Analysis of Contact Pressure Profile of Airless tires as compared to Conventional Tires 

      Ludvigsen, Søndre; Andleeb, Zahra; Khawaja, Hassan; Moatamedi, Mojtaba; Alzahabi, Basem (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-15)
      The harsh climate of the Arctic has always posed significant challenges to car drivers. The severe loss in traction due to snow and icing on the roads has led to an increased risk of collisions. The purpose of this work is to replace the conventional air-filled tire with a non-pneumatic tire to improve the grip in the Arctic conditions. The grip obtained for tires is determined by the weight of the ...
    • Multiphysics Analysis of Ice-Polyurethane Adhesion under Flexural Loading using FEM Analysis 

      Eidesen, Hans-Kristian; Andleeb, Zahra; Khawaja, Hassan; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-12-26)
      This paper presents the Finite Element Analysis (FEA) Multiphysics technique, applied to study the strength of ice adhesion between the surface of polyurethane and ice. The theoretical study of this work is based on the Euler-Bernoulli beam theory that is used to solve a four-point bending problem to give the correlation of displacements with load and longitudinal stresses. The physical samples were ...
    • Multiphysics based Analysis of Materials for Roads in Cold Regions to Prevent Ice Adhesion and Low-Temperature Crack Developments 

      Andleeb, Zahra; Khawaja, Hassan; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-12)
      Roads constitute a significant hazard if the effects of wintertime are not handled well. After a heavy snowfall, the most dangerous factor is a slippery surface due to ice adhesion with the asphalt pavement. The ice on roads increases the risk of road accidents and, upon melting, contributes to the formation of Low-Temperature Cracks (LTCs) and potholes. This research explores the physical ...
    • Multiphysics based Modal and Harmonic Analysis of Axial Turbines 

      Khawaja, Hassan; Andleeb, Zahra; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-03-15)
      The presented work discusses the vibration behavior of an axial turbine, analyzed using the finite element method (FEM) using commercial software ANSYS®. The turbine was modeled as a 2-D plate type of structure discretized with 4-noded shell 63 elements to save computational time. Constraints were applied keeping in view the actual operating conditions. The turbine was modeled with more than one FE ...
    • Multiphysics Eulerian-Lagrangian Electrostatic Particle Spray- And Deposition Model for OpenFOAM® and KaleidoSim® Cloud-Platform 

      Boiger, Gernot; Boldrini, M; Lienhard, V; Siyahhan, B; Khawaja, Hassan; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2020)
      A finite volume based Eulerian-Lagrangian model has been created within OpenFOAM® in order to predict the behavior of particle clouds as well as particle deposition thicknesses on substrates under the influence of electro-static effects. The model resolves close to electrode effects as well as phenomena within the entire deposition chamber. It considers fluid dynamic effects, particle inertia, ...
    • Multiphysics Impact Analysis of Carbon Fiber Reinforced Polymer (CFRP) Shell 

      Strand, Cathrine Høgmo; Andleeb, Zahra; Khawaja, Hassan; Moatamedi, Mojtaba (Journal article; Peer reviewed, 2019-07-30)
      With increasing popularity of Carbon Fiber Reinforced Polymer (CFRP) over time, the need for research in the field has increased dramatically. Many industries, i.e. aeronautical, automotive, and marine are opting to install carbon fiber in their structures to account for harsh environments like cold temperatures applications, but the research on the temperature exposure behavior of the materials are ...
    • Multiphysics modeling of wind turbines 

      Soleiman Fallah, Arash; Khawaja, Hassan Abbas; Moatamedi, Mojtaba (Chapter; Bokkapittel, 2024)
      According toThe International SocietyofMultiphysics (“Definition— MULTIPHYSICS”),multiphysics (sometimes spelledasmulti-physics) is defined as a coupled modeling approach of studies that demands simultaneous addressing of hitherto separate physical disciplines and combining them to generate relational mathematical models and validate them with controlled experiments to enhance the understanding of ...
    • Multiphysics Modelling of Powder Coating of U-Profiles: Towards Simulation-based Optimization of Key-Performance Attributes by Variation of Powder-Parameters 

      Boiger, Gernot; Siyahhan, Bercan; Soleiman Fallah, Arash; Khawaja, Hassan; Moatamedi, Mojtaba (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-06-13)
      Multiphysics simulation software has been developed to predict the key performance attributes of industrial powder coating applications based on applied process-parameter settings. The software is a Eulerian-Lagrangian finite-volume Multiphysics solver based on OpenFOAM, capable of modelling mass transfer effects between powder-coating pistols and electrically grounded metallic substrates. It considers ...