Lenka Lausova

Effect of Non-Uniform Temperature Distribution over the Cross-Section in Steel Frame Structure

The paper deals with the effect of non-uniform temperature over the cross-section in the steel frame structure under fire loading. The unequal temperature distribution causes additional bending moments in statically indeterminate structures. Numerical results of thermal and structural analysis from the commercial computer software ANSYS are compared with the experimental measurements on the steel frame exposed to high temperature.

Experimental and Numerical Analysis of Steel Frame Structure Exposed to High Temperature

Abstract Structures exposed to fire loading, where supports prevent thermal expansions, must be calculated according to the basic principles of mechanics while respecting the effect of rising temperature on the structure and its effect on the value of variable material properties at the time of fire. The paper analyzed and compared results of the experiment aimed to verify the behavior of statically indeterminate steel frame exposed to high temperature and numerical modelling using finite element method in the ANSYS software.

Dynamic Heat Transfer through the External Wall of a Timber Structure

The article compares results of temperature and heat flux measurements in the external wall of a real timber structure with results obtained by numerical modeling using the finite element method in the ANSYS software. The measured temperature values are compared with results obtained from numerical simulation of dynamic heat transport using non-stationary boundary conditions. In the article there is evaluated a suitability of theoretical numerical calculations for a thermal field and heat flux prediction in a building structure.

Experimental Measurements and Numerical Simulations of Dynamic Thermal Performance of External Timber Frame Wall

The aim of this article is to contribute to the summer thermal performance of external timber frame wall by the simultaneous use of experimental measurements and numerical simulations. The measurements were taken on an experimental timber frame passive house. The numerical modeling of the external wall using a dynamic simulation program ANSYS. The results of research are presented and discussed. It is shown that the numerical simulation methods are suitable tools for the prediction of thermal behaviour of light-weight timber-based construction.

Numerical Models of Wind Effects on Temperature Loaded Object

Wind climate influencing wind loads on buildings and other structures, as well as the dispersion of pollutants from various surfaces is essentially determined by small-scale motions and processes occurring in the atmospheric boundary layer (ABL). The physical and thermal properties of the underlying surface, in conjunction with the dynamics and thermodynamics of the lower atmosphere influence the distribution of wind velocity in thermally stratified ABL. Atmospheric turbulence is characterized by a high degree of irregularity, three-dimensionality, diffusivity, dissipation, and a wide range of motion scales. This article describes a change of selected turbulent variables in the surroundings of flow around a thermally loaded object. The problem is solved numerically in Ansys Fluent 13.0 software using LES (Large eddy simulation) models as well as the Transition SST (Shear Stress Transport) model that is able to take into account the difference between high and low turbulence at the interface between the wake behind an obstacle and the free stream. The results are mutually compared and verified with experimental measurements in the wind tunnel.

Numerical and Experimental Models of the Thermally Stratified Boundary Layer

Abstract The article describes a change of selected turbulent variables in the surroundings of a flow around thermally loaded object. The problem is solved numerically in the software Ansys Fluent using a Transition SST model that is able to take into account the difference between high and low turbulence at the interface between the wake behind an obstacle and the free stream. The results are verified with experimental measurements in the wind tunnel.

Numerical Calculation of Aerodynamic Roughness of Chimney Jacketed with Corrugated Sheets

Abstract The article deals with the influence of a shape of smokestack casing on the total load from wind effects. It describes possibilities of defining an equivalent aerodynamic roughness and aerodynamic drag coefficient for numerical modelling of the flow around a circular cylinder. The aim of this study is to solve the force coefficient for the smokestack of a cylindrical shape, which is jacketed with shaped sheets. The flow around a smokestack is solved in the ANSYS Fluent software using the DES model.

Numerical Calculation of the Force Coefficient for Cylindrical Shape Smokestack Covered with Corrugated Iron

The article deals with the influence of a shape of the smokestacks casing on the final load from wind effects. It describes possibilities of defining an equivalent aerodynamic roughness and aerodynamic drag coefficient for numerical modelling of the flow around a circular cylinder. The aim is to determine the force coefficient for a smokestack of a cylindrical shape, which is sheeted with corrugated sheet metal. The flow around a smokestack is solved in software Ansys Fluent using the DES model.

Numerical and Experimental Modelling of an Air Flow Field in the Chamber of a Rectangular Cross-Section Contraction

The article describes the study of turbulent characteristics in the enclosed chamber of a rectangular corss-section nozzle using numerical calculations. Suitable Ansys Fluent software models were selected based on the measurements results comparison in an aerodynamic tunnel as the fluid exits the nozzle. Special attention is paid to profile velocity near the peripheral wall of the observed enclosed chamber in order to confirm the optimal shape of the contraction and thus take steps towards a high quality velocity field.

Influence of Rectangular Holes on Stability of Three-Layer Plates

Grounded on the theory of thin shells and with application of generalized functions elements is solved the problem on critical compressive loading definition of three-layered rectangular plate with limited length through cut. The method of consideration of single limited length cut in parallel of one of rectangular sides in plane is spread on consideration of rectangular hole as four cuts should create the closed rectangular contour, and therefore, are simulating the hole. Due the various selections of approximation functions is proposed to also consider various types of boundary conditions.