A5000384886- Solidification and crystal growth phenomena
- Metallurgical Processes and Thermodynamics
- Aluminum Alloy Microstructure Properties
- Radiative Heat Transfer Studies
- Building energy efficiency and sustainability
- Advanced Numerical Methods in Computational Mathematics
- Renewable energy and sustainable power systems
- Numerical methods in inverse problems
- Engine and Fuel Emissions
- Combustion and flame dynamics
- Advanced Mathematical Modeling in Engineering
- Integrated Water Resources Management
- Mechanical and Thermal Properties Analysis
- Metallurgy and Material Forming
- Phase Change Materials Research
- Advanced Combustion Engine Technologies
- Material Properties and Applications
- Nanofluid Flow and Heat Transfer
- Adsorption and Cooling Systems
- Environmental and Industrial Safety
- Electromagnetic Simulation and Numerical Methods
- Advancements in Materials Engineering
- Numerical methods in engineering
- Aerodynamics and Fluid Dynamics Research
- Heat Transfer and Optimization
Warsaw University of Technology
2010-2021
University College Dublin
2005-2006
Lublin University of Technology
2005
Boeing (Canada)
2002
University of Toronto
2002
Instytut Chemii i Techniki Jądrowej
2000
University of Warsaw
1990
Abstract A semi-implicit finite element method (FEM) is presented for the two-dimensional computer simulation of solid-liquid phase change controlled by natural convection and conduction. The algorithm based on a combination (1) projection to uncouple velocity calculations from pressure incompressible fluid flow, (2) backward Euler explicit Adams-Bashforth schemes effectively integrate diffusion advection in time, (3) an enthalpy-porosity approach account latent heat effect fixed grid....
Abstract Behavioral errors of an approximate solution, resulting from violation fundamental physical constraints occurring in a diffusion transport phenomenon, are compared for Ike weighted residual-based and control volume-based finite element methods. Because its background, the latter method offers higher accuracy, better stability oscillation characteristics, preservation discrete maximum principle coarse time-space discretization grids. Furthermore, it gives simple, physically justified...
Abstract This paper is concerned with the development of a numerical model which based on direct integral balance internal energy over an priori defined subdomain, associated any nodal point, and piecewise temperature geometrical interpolation inherent in isoparametric finite element concept. discretization procedure, also called conservative method (CFEM), ensures local global conservation, spite errors, preserves major feature technique, i.e. versatility its algorithm. The CFEM equations...
A front-tracking technique on a fixed Cartesian grid, based the kinetics of dendritic growth, is used to model progress an undercooled columnar front in non-equilibrium 2D solidification controlled by conduction and thermal natural convection. The effect alloy latent heat fusion included this single-domain through careful definition source terms energy conservation equation account for both advance subsequent thickening mushy zone within control volume. compared with enthalpy approach...
Chemical inhomogeneity, developing in a solidifying binary alloy cast and manifesting by spatially distributed heterogeneity of the solute composition formation local highly solute-rich channels, is known severe defect casting products. The paper involves discussion on reliable efficient multi-scale computer simulations this phenomenon. proposed computational model based commonly used enthalpy-porosity approach but combined with direct tracking hypothetical interface separating stationary...
Abstract Purpose The purpose of this study is to developed a simplified thermo-fluid model an engine cowling in small airplane. An aircraft system composed different elements operating at various temperatures and conjunction with the composite nacelle creates region high intensity heat transfer be covered by cooling/ventilation systems. Therefore thermal analysis, accounting for complex modes, necessary order verify that adequate cooling ensured are maintained within limits throughout whole...
The paper explores the potential of a recently developed special front tracking method in identification interface between columnar and equiaxed structures formed during binary alloy solidification, driven by thermosolutal convection. method, based on theoretical experimental dendrite tip kinetics, is capable directly distinguishing mush undercooled liquid/equiaxed region developing ahead curve. A new numerical model its computational algorithm are proposed, where classical Eulerian volume...
The dendrite tip kinetics model accuracy relies on the reliability of stability constant used, which is usually experimentally determined for 3D situations and applied to 2D models. paper reports authors` attempts cure situation by deriving dendritic scaling parameter aluminium-based alloy: Al-4wt%Cu. obtained then incorporated into KGT growth in order compare it with original counterpart derive two-dimensional three-dimensional versions modified Hunt's analytical columnar-to-equiaxed...
Purpose – The purpose of this paper is to endorse the idea using a special post-calculating front tracking (FT) procedure, along with enthalpy-porosity (EP-FT) single continuum model, in order identify zones different dendritic microstructures developing mushy zone during cooling and solidification binary alloy. Design/methodology/approach 2D 3D algorithms FT approach crystal growth laws were implemented macroscopic calculations alloy identification dendrite process. Findings Direct...
The main objective of the research project European Space Agency (ESA) - Microgravity Application Promotion (MAP) programme entitled Columnar-to-Equiaxed Transition in SOLidification Processing (CETSOL) is investigation formation transition from columnar to equiaxed macrostructure that takes place casting. Indeed, grain structures observed most casting processes metallic alloys are result a competition between growth several arrays dendrites develop under constrained and unconstrained...
An ensemble averaging technique is used to obtain both macroscopic equations of transport phenomena in a two-phase region and new models permeability thermal conductivity the columnar mushy zone through analysis most likely configurations local microstructure. The obtained formulae are incorporated into FEM computer code for binary mixture solidification with convection. influence various on temporal shapes as well velocity temperature fields studied test case dilute solution ammonium...
The as-cast properties of components with a columnar grain structure are very different from those an equiaxed one. Under certain solidification conditions, zones both structures can occur in alloy casting; the boundary between is columnar-to-equiaxed transition (CET). A front-tracking model dendritic has been developed, which predict nucleation and growth solid undercooled liquid during casting process. process described by dendrite tip kinetics, fully coupled to fixed-grid control volume...
Purpose Numerical models of manufacturing processes are useful and provide insight for the practitioner; however, model verification validation a prerequisite expedient application. This paper aims to detail code-to-code thermal numerical Bridgman solidification process alloys in two-dimensional axisymmetric domain, against an established commercial code (ANSYS Fluent); work is considered confidence building step development. Design/methodology/approach A grid sensitivity analysis carried...
Abstract Heat flow in heterogeneous media with complex microstructure follows tortuous path and therefore determination of temperature distribution them is a challenging task. Two-scales, micro-macro model heat conduction phase change such was considered the paper. A relation between on microscopic level, i.e., level details microstructure, macroscopic where properties were homogenized treated as effective, derived. The expansion applied to this allowed obtain its more simplified,...
Purpose Proper selection of the stability parameter determines accuracy dendrite tip kinetics at a single crystal scale. Recently developed sophisticated phase field modelling grain evolution provides evidence that this is not constant during process. Nevertheless, in commonly used micro-macroscopic simulations alloy solidification, it common practice to use value parameter, resulting from marginal theory. This paper aims address issue how inaccuracy growth can influence numerically...
A semi-implicit operator splitting technique is combined with an enthalpy-porosity method to solve both isothermal and temperature range solidification on equal- unequal-order finite element grids. The performance of the presented algorithm studied by solving some benchmark problems including a driven cavity flow, free convection (with without Boussinesq approximation) binary alloy solidification. Solutions obtained are from wiggles spurious pressure modes they fit fairly well results...