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A significant level of research is currently being carried out in the development of driver support systems as they are expected to play a key role in minimizing road vehicle accidents and creating a safe driving environment under harsh weather conditions. However, the performance of some components used by existing driver support systems like LIDAR and visual cameras are affected by extreme weather conditions such as heavy rain fall and snow. Therefore, it is paramount to identify key locations in an automotive vehicle where such systems are least affect by external weather conditions, thereby, improving their overall performance. The field of research that deals with such questions from a simulation perspective is called contamination modeling. At the moment, one of the biggest knowledge gaps in this field is how to consider the effect of different materials on the movement of liquids such as water on different automotive surfaces like glass, plastic, rubber and painted metal. The work presented in this research study has been carried out to investigate and establish the most suitable simulation strategies to match numerical predictions with experimental data for flow of water over different automotive surfaces. Following a comprehensive parametric study of simulation parameters, it was found that the most suitable model that can be tweaked to achieve different flow properties with different surfaces is a dynamic contact angle model. The Blended Kistler model available in STAR-CCM+ required specific values for static, advancing and receding contact angles to optimize a surface for a given material. Therefore, droplet experiments of two droplet sizes were initially carried out for all tested materials at different inclinations and necessary flow parameters were recorded. All experiments were carried out using an approach known as light induced fluorescence imaging where the captured images provided a very convenient method for post processing in computational softw

A significant level of research is currently being carried out in the development of driver support systems as they are expected to play a key role in minimizing road vehicle accidents and creating a safe driving environment under harsh weather conditions. However, the performance of some components used by existing driver support systems like LIDAR and visual cameras are affected by extreme weather conditions such as heavy rain fall and snow. Therefore, it is paramount to identify key locations in an automotive vehicle where such systems are least affect by external weather conditions, thereby, improving their overall performance. The field of research that deals with such questions from a simulation perspective is called contamination modeling. At the moment, one of the biggest knowledge gaps in this field is how to consider the effect of different materials on the movement of liquids such as water on different automotive surfaces like glass, plastic, rubber and painted metal. The work presented in this research study has been carried out to investigate and establish the most suitable simulation strategies to match numerical predictions with experimental data for flow of water over different automotive surfaces. Following a comprehensive parametric study of simulation parameters, it was found that the most suitable model that can be tweaked to achieve different flow properties with different surfaces is a dynamic contact angle model. The Blended Kistler model available in STAR-CCM+ required specific values for static, advancing and receding contact angles to optimize a surface for a given material. Therefore, droplet experiments of two droplet sizes were initially carried out for all tested materials at different inclinations and necessary flow parameters were recorded. All experiments were carried out using an approach known as light induced fluorescence imaging where the captured images provided a very convenient method for post processing in computational softw

Spaces of discrete differential forms can be applied to numerically solve the partial differential equations that govern phenomena such as electromagnetics and fluid mechanics. Robustness of the resulting numerical methods is complemented by pointwise satisfaction of conservation laws (e.g., mass conservation) in the discrete setting. Here we present the construction of isogeometric discrete differential forms, i.e., differential form spaces built using smooth splines. We first present an algorithm for computing Bézier extraction operators for univariate spline differential forms that allow local degree elevation. Then, using tensor-products of the univariate splines, a complex of discrete differential forms is built on meshes that contain polar singularities, i.e., edges that are singularly mapped onto points. We prove that the spline complexes share the same cohomological structure as the de Rham complex. Several examples are presented to demonstrate the applicability of the proposed methodology. In particular, the splines spaces derived are used to simulate generalized Stokes flow on arbitrarily curved smooth surfaces and to numerically demonstrate (a) optimal approximation and inf–sup stability of the spline spaces; (b) pointwise incompressible flows; and (c) flows on deforming surfaces., Numerical Analysis

Spaces of discrete differential forms can be applied to numerically solve the partial differential equations that govern phenomena such as electromagnetics and fluid mechanics. Robustness of the resulting numerical methods is complemented by pointwise satisfaction of conservation laws (e.g., mass conservation) in the discrete setting. Here we present the construction of isogeometric discrete differential forms, i.e., differential form spaces built using smooth splines. We first present an algorithm for computing Bézier extraction operators for univariate spline differential forms that allow local degree elevation. Then, using tensor-products of the univariate splines, a complex of discrete differential forms is built on meshes that contain polar singularities, i.e., edges that are singularly mapped onto points. We prove that the spline complexes share the same cohomological structure as the de Rham complex. Several examples are presented to demonstrate the applicability of the proposed methodology. In particular, the splines spaces derived are used to simulate generalized Stokes flow on arbitrarily curved smooth surfaces and to numerically demonstrate (a) optimal approximation and inf–sup stability of the spline spaces; (b) pointwise incompressible flows; and (c) flows on deforming surfaces., Numerical Analysis

Based on the results of Aerogamma spectrometric examination of morphological and geological-structural analysis, for explore the content of natural radionuclides in groundwater and surface water, the basin of Vranje area (Southern Serbia) was selected. On the area of 500 km2, the samples were collected from springs, wells, boreholes and surface flows. The water contents were determined by U, 226Ra, 222Rn, gases (O2, CO2, H2O), anion-cation composition, trace elements, pH value, Eh, Ec, water hardness and mineralization. Data analysis was performed according to the geology, in volcanoclastic sedimentary and metamorphic complex of the area of Vranjska Spa-Leskovac. In the area of Vranje Spa anomalous uranium content in groundwater and surface water, and mineralization in the volcanoclastic sediments have been identified. The warmest water source in borehole with temperature of 91-93 ºC is located in the area of Vranje Spa. The research results will be shown with tables and geochemical map 1: 50000.

Based on the results of Aerogamma spectrometric examination of morphological and geological-structural analysis, for explore the content of natural radionuclides in groundwater and surface water, the basin of Vranje area (Southern Serbia) was selected. On the area of 500 km2, the samples were collected from springs, wells, boreholes and surface flows. The water contents were determined by U, 226Ra, 222Rn, gases (O2, CO2, H2O), anion-cation composition, trace elements, pH value, Eh, Ec, water hardness and mineralization. Data analysis was performed according to the geology, in volcanoclastic sedimentary and metamorphic complex of the area of Vranjska Spa-Leskovac. In the area of Vranje Spa anomalous uranium content in groundwater and surface water, and mineralization in the volcanoclastic sediments have been identified. The warmest water source in borehole with temperature of 91-93 ºC is located in the area of Vranje Spa. The research results will be shown with tables and geochemical map 1: 50000.

Three new approaches to hydrodynamic flow visualization on surfaces were evaluated: shear-sensitive liquid crystals, high-viscosity dot fluids, and optically monitored compliant coatings. Liquid crystal mixtures were highly successful, producing high-resolution observations of both steady and unsteady boundary layer separation and transition characteristics. Dot fluids of high viscosity were not superior to low-viscosity fluids thickened with pigment, but minor differences in behavior occurred among the four base fluids used. Optical methods of detecting shear- or pressure-induced displacements of compliant coatings were unsuccessful in a water tunnel environment., Original contains color plates: All DTIC and NTIS reproductions will be in black and white.