Abed Alaswad

Employment of finite element analysis and Response Surface Methodology to investigate the geometrical factors in T-type bi-layered tube hydroforming

Bi-layered tubing which consists of two different metallic layers is recommended to use in complex working environments as it offers combined properties that single layer structure does not have. However, in this wok, producing of T-shape bi-layered components using the tube hydroforming process is investigated. In this regard, the bulge height and the wall thickness reduction of the bi-layered hydroformed parts (responses) are modelled as functions of the geometrical factors using the combination of the finite element modelling (FEM) and Response Surface Methodology (RSM) for design of experiments (DOE). The geometrical factors effects and their interactions on the responses were determined and discussed. Based on the resultant models, a multi-response optimization study was conducted. Furthermore, for the optimum solutions, a significant agreement was indicated between the predicted and numerical values.

Finite element comparison of single and bi-layered tube hydroforming processes

Abstract In this paper, single and bi-layered tube hydroforming processes were numerically simulated using the finite element method. It was found that the final bulges heights resulted from the models were in good agreement with the experimental results. Both types of modeling have been kept with the same geometry, tube material, and process parameters to compare between the obtained hydroformed products (branch height, thickness reduction, and wrinkling) using different loading path types. Results were discussed.

An Analytical Comparison of Single and Bi‐layered Tube Hydroforming Systems Using Finite Element Method

Tube hydroforming is a type of unconventional metal forming process in which high fluid pressure and axial feed are used to deform a tube blank in the desired shape. Single and bi‐layered tubular components can be produced by this method. In this paper, single and bi‐layered tube hydroforming processes were numerically simulated using finite element method. It was found that the developed branch height resulted from the models was in good agreement with the experimental results. Both types of modeling have been kept with the same thickness, tube material, and process parameters to compare between the obtained hydroformed products (Branch height, Thickness reduction, and wrinkle height). Results were discussed.

Experimental and finite element investigation of formability and failures in bi-layered tube hydroforming

Optimization of the operating conditions is one of the most significant studies in the hydroforming process, which affect the forming of successful components. In this work, a finite element model was established for bi-layered tube hydroforming process using ANSYS LS-DYNA pre-processor and LS-DYNA solver in order to predict the most efficient and acceptable operating condition for certain material properties and initial blank geometry. Experiments were conducted to check the model validation and the resultant bulge height and thickness reduction were seen in good agreement with the numerical results. The major failure modes of the process were investigated. Different sets of loading paths (relations between axial feed and internal pressure) were tested and compared to each others. Applying internal pressure in advance of the axial pushing was found to give the best formability for the process.

Multi‐response Optimization of Geometrical Factors in Bi‐layered Tube Hydroforming

In the last years many researchers were concentrating to develop and design new unconventional metal forming processes. Among such new technologies, tube hydroforming was proved as one of the most promising. Geometries of the tube and die were found to have significant effects on the hydroformed part. Based on the mathematical models, which describe the effect of the geometrical factors on bi‐layered tube hydroforming, a multi‐response optimization study was proposed in this paper with the aim to achieve different quality objectives for two different criteria. The optimal geometrical factors of bi‐layered tube hydroforming combinations were tabulated and discussed.

Fuel Cell Technologies, Applications, and State of the Art. A Reference Guide

The reliance upon fossil fuels is one of the most important problems that we have to deal with nowadays, because using them is highly not sustainable, and leads to serious environmental issues, such as air pollution and global warming, beside its negative effect on the economic security and development. Alternatively, environmental-friendly, sustainable, efficient new power sources are needed. Among all of the different technologies associated with the renewable energy, fuel cell technologies represent one of the most promising ones. In this article, an overview of the technology and its advantages and disadvantages compared with competitive technologies was revealed. Application of different types of fuel cells is covered in the stationary, portable and transport power sectors. Furthermore, a special focus was made on the proton exchange membrane (PEM) fuel cells; in that its structure was studied in detail. The current limitation and promising development in PEM technology were stated.

A numerical and experimental study of a new design of closed dynamic respiration chamber

Carbon dioxide soil efflux modelling in closed dynamic respiration chambers is a challenging task. This is attributed on many occasions to the very small concentrations of carbon dioxide being transported between soil and the atmosphere. This paper describes a portable device which was made exclusively to accurately measure carbon dioxide efflux from soil locations. The blowing fan creates a forced convective flow to occur in the chamber making the K-Epsilon turbulence model a necessity to model the occurring flow in the respiration chamber gas domain. Furthermore the Darcy model is applied on the porous domain to model the flow pattern within the soil. The measurement process was achieved through measuring carbon dioxide concentration, temperature and relative humidity inside the chamber in relation to time. Simulation and experimental data is obtained using ANSYS and MATLAB. A significant agreement between the experimental and numerical results was achieved.

Study on the Key Factor Parameters to Increase Productivity in Construction and Manufacturing Industries.

Proper management of human and non-human resources in construction and manufacturing projects can give-in considerable savings in time and cost. Construction and Manufacturing industry faces issues in connection with problems related with productivity and the problems are usually connected with performance of employees. The performance of employees is affected by many factors. In this paper a survey was made on respondents who are employed various projects of Saudi Arabia. The researcher developed a theoretical framework from the existing research which was used as a Model to collect and analyze the field data to test the hypothesis. In this research activity three predictors (commitment, job satisfaction and job performance) for determining the change in productivity. The results highlight that commitment and job performance (respectively) are the two predictors which are explaining 37% of variation in the productivity of the companies. The results also show that Job Satisfaction has no role in the prediction of productivity.

Mathematical Modeling of Weld Phenomena, Part 2: Design of Experiments and Optimization

The objective of this chapter is to give an essential presentation on the theory and practice of implementing modeling and optimization techniques to evaluate the welding process. This chapter includes comprehensive research works on the Design of Experiments (DoE.) The application of DoE, evolutionary algorithms, and computational network are widely used to develop a mathematical relationship between the welding process input parameters and the output variables of the weld joint in order to determine the welding input parameters that lead to the desired weld quality.

Optimization Techniques in Material Processing

The objective of this chapter is to give an essential presentation on the theory and practice of implementing modeling and optimization techniques to evaluate different manufacturing process for a wide range of materials. This chapter includes comprehensive research works on the Design of Experiments (DoE), and the Artificial Neural Network (ANN) that is widely used to develop a mathematical relationship between the process input parameters and the output.