Constantin Opran

Ultrasonic System Design and Calculation for Polymer Metallization

Paper presents ultrasonic system design and calculation for metallization process of the polymer pieces. Because of some bad properties like: very low hardness, very low wear resistance, no electrical conductivity and no open fire resistance, polymer parts has to be reinforced with different materials. A new method is represented by ultrasonic field metallization process which has certain advantages. The work presents the analytic calculation for the ultrasonic field and vibration modes of the ultrasonic system used for a polymer base material ultrasonic activation.

Methods and Special Functions Used in Diffusion Modelling

Natural phenomena can be modelled adequately precise with differential equations. An example of such phenomena is diffusion. All differential equations with partial derivatives, of two variables and of the second order, which model the diffusion are parabolic with simple solutions. This simple solution is: erf(x), exponential functions or power series. Adding new differential terms requires the use of more complicated functions, some degenerated, modified or confluent, of real or imaginary variables. This functions are: Bessel, Kummer, Whittaker, Hermite, hyper-geometrical or Heun. The benefit of using these functions lies in greater clarity and precision in mathematical expression. Modelling methods by change-of-variable and function, adding new differential terms and transformations of special functions increase modelling possibilities of convective diffusion in different environments using differential equations. The paper presents a novel approach to diffusion modelling for dry corrosion.

Innovative Design of Polymeric Systems Used in Manufacturing of Gear Pumps

This paper present the results of the researches regarding innovative design of polymeric systems used in manufacturing of gear pumps with application to reversible pumps used both as pumps as well as motors or steps of the flow dividers. It shows the description of reversible gear pump, with compensating seal in the innovative variant and compensation sealing system for reversible pumps – innovative design. For this innovative solution has been developed a system of compensation sealing kit for reversible pumps – innovative design. In order to obtain these products was necessary to make molds for vulcanization and injection molding tools for polymeric products having special construction considering the size and special profile products. They highlight the competitive advantages of innovative compensation sealing system made by polymeric products. The paper also shows numerical analysis of the fluid at gear pumps using innovative compensation sealing proving the correctness and the advantages of new variants of sealing. The performances reversible pump that uses innovative new sealing system are homogeneous and high levels of performance than those with seals in the classic system.

Research Regarding Adaptive Design of Gear Pumps Used for Polymeric Products Engineering

This paper present the results of the researches regarding innovative and adaptive design of gear pumps for engineering of polymeric products with application in production of injection molding machine. It shows the description of gear pump with innovative design and double gear pump – innovative design, highlighting innovative design feature through constructive adaptation depending on requirements, having (30 – 40) % smaller at the axial size, compared to the classic pumps. They highlight the competitive advantages of innovative pumps with superior technological parameters. The paper also shows numerical simulation of technological parameters for pumps in innovative and adaptive variant proving the correctness and the advantages of new variants. Using the innovative variant allows the development a family of gear pumps, single and double, extremely compact, robust, reliable and with low manufacturing costs.

Sheet Moulding Compounds of Large Auto Body Parts Made from Polymeric Composite

The paper presents the parameter influence on the process of pressing aids in reinforced thermosetting polymer mold blanks Sheet Moulding Compound type (SMC) used to obtain large pieces of automotive bodywork. In the first part of the paper presents complex recipe constitutive factors of R-SMC prepreg, analyzing and choosing the optimal tehnnology of each component type, depends on the application blank piece and specific technical and economic parameters. Further the paper presents the influence of compression parameters (time, pressure, temperature) on the pressing process and optimize the parameters for each blank so that the reproducibility of the mass production process of obtaining large parts of Figures Size automotive to be insured. Finally it presents a model highlighting induced reorientation of fibers in the manufacture of SMCs as if prepregs of R-SMC, there is a dependency between the SMC belt speed production and planar orientation of the fibers in the direction of forward her.

Cloud Community for Polymeric and Composites Simulations Products

The paper presents the development of a scientific cloud computing community for polymeric and composites products that offers high performance computation capability. The scientific research community will use the cloud to resolve complex issues. This community will include data storage, a polymeric materials encyclopaedia, softwares for simulation, design, so will determine a functional independence. Cloud computing will increase the productivity and innovation in all polymeric and composites field. The software platform consists of several virtual machines running a Unix (or derivatives as Linux or *BSD’s) operating systems using specialised software, Open Source software for materials and process modeling, a scientific package for polymeric material simulations.

A Model Regarding Material Removal Using FEM at Ultrasonic Aided EDM of Metal Matrix Composites

The paper deals with phenomena occurring at the ultrasonic aided electrical discharge machining (EDM-US) of electro-conductive metal matrix composites materials (EC-MMCs-Al/Al2O3p). Starting from the analysis of the cavitational phenomena due to the forced ultrasonic longitudinal vibrations of the electrode and the phenomena caused by the thermal shock, a physical-mathematical model of the material removal process was developed consisting mainly by boiling, vaporization and spalling. Based on the Finite Element Method (FEM), the thermal shock phenomenon, as well as its influence on the material removal process, is described.

Numerical analysis of laser paint removal from various substrates

Numerical simulation results obtained in investigating laser paint removal from different metal substrates, mainly aluminum and aluminum alloys, are presented. The main purpose of the developed simulation model is to define the laser installation specifications required for an operation that does not affect the substrate on which the paint is deposited. This is an important laser application in aeronautical industry. The developed simulation model considers transverse laser beam intensity distribution and, consequently, the temperature distribution in the processed mechanical component.

Researches Concerning Structural and Mechanical Behavior of Sandwich Composite Polymeric Products

The sandwich composite polymeric products have a wide utilization in various fileds like aircraft and automotive construction, load bearing structures, sports equipment, more specifically, wherever weight-saving is required. Sandwich composites polymeric products represent excellent examples of the potential offered by composite materials. The combination of two composite faces and a lightweight polystyrene core allows obtaining a high flexural stiffness with a weak mass. This paper deals with the analysis of the structural and mechanical behavior properties of the core, adhesive and faces, for sandwich composite polymeric products. There are also presented the investigation results on how different specific factors like: mechanical and structural behavior, interface between the faces and core, constant force resistance in time, the reinforcing elements (fiber glass), the polyester core do influence the machinability of sandwich composites polymeric products..