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Automated guided vehicles have been widely used in flexible manufacturing systems especially in a job shop and flow shop. Recently, they are included in other fields such as container terminals. This paper demonstrates a literature review of the last three decades about the scheduling problems of the automated guided vehicles in three main classes, namely job shops, flow shops, and container terminals. We classify the literature according to the scheduling problems and the solution approaches. The results of the survey are that the solution methods mainly focus on using simulation as a key performance analysis tool, whereas, the big computation times of the developed mathematical models make heuristics approaches are dominant for solving such models. After that, we discuss research gaps to the purpose of finding new research directions.

Automated guided vehicles have been widely used in flexible manufacturing systems especially in a job shop and flow shop. Recently, they are included in other fields such as container terminals. This paper demonstrates a literature review of the last three decades about the scheduling problems of the automated guided vehicles in three main classes, namely job shops, flow shops, and container terminals. We classify the literature according to the scheduling problems and the solution approaches. The results of the survey are that the solution methods mainly focus on using simulation as a key performance analysis tool, whereas, the big computation times of the developed mathematical models make heuristics approaches are dominant for solving such models. After that, we discuss research gaps to the purpose of finding new research directions.

Automated guided vehicles have been widely used in flexible manufacturing systems especially in a job shop and flow shop. Recently, they are included in other fields such as container terminals. This paper demonstrates a literature review of the last three decades about the scheduling problems of the automated guided vehicles in three main classes, namely job shops, flow shops, and container terminals. We classify the literature according to the scheduling problems and the solution approaches. The results of the survey are that the solution methods mainly focus on using simulation as a key performance analysis tool, whereas, the big computation times of the developed mathematical models make heuristics approaches are dominant for solving such models. After that, we discuss research gaps to the purpose of finding new research directions.

A numerical simulation of transport phenomena in the photo-electrochemical (PEC) reactor is performed. The transport phenomena equations include the NaviereStokes, the respective energy equation for electrolyte, and the radiative transfer equation (RTE). Two different designs, design A, and design B of photoelectrochemical reactors are suggested. The hydrogen production rate and solar-to-hydrogen efficiency are estimated for each design at different solar incident flux ranged from 500 to 2000 W/m2 in increments of 500 W/m2. Results have shown that the solar-to-hydrogen efficiency increases as solar flux increases for both designs. Its predicted values could reach 12.8% for design A, and 13.1% for design B. Moreover, by increasing the solar incident flux, the hydrogen volume production rate is increased as well. It is found to be 79 L/m2.h for design A, and 85.4 L/m2.h for design B. Comparison between currently predicted results and previous data indicates an enhancement of solar-to-hydrogen efficiency and hydrogen production that can be achieved with the suggested design.

A numerical simulation of transport phenomena in the photo-electrochemical (PEC) reactor is performed. The transport phenomena equations include the NaviereStokes, the respective energy equation for electrolyte, and the radiative transfer equation (RTE). Two different designs, design A, and design B of photoelectrochemical reactors are suggested. The hydrogen production rate and solar-to-hydrogen efficiency are estimated for each design at different solar incident flux ranged from 500 to 2000 W/m2 in increments of 500 W/m2. Results have shown that the solar-to-hydrogen efficiency increases as solar flux increases for both designs. Its predicted values could reach 12.8% for design A, and 13.1% for design B. Moreover, by increasing the solar incident flux, the hydrogen volume production rate is increased as well. It is found to be 79 L/m2.h for design A, and 85.4 L/m2.h for design B. Comparison between currently predicted results and previous data indicates an enhancement of solar-to-hydrogen efficiency and hydrogen production that can be achieved with the suggested design.

Swirl generation is an important parameter inside the diesel engine cylinder as it achieves good mixing of air and fuel which has a great influence on the combustion efficiency, engine emissions, and soot formation. The generated swirl intensity by the inlet port and the inlet valve configuration is usually measured on a steady flow test rig using an impulse torque meter. In this paper, an experimental investigation using steady flow test rig was performed on an engine cylinder having a helical-spiral inlet port and shrouded inlet valve. Three valve shrouds were used, they are; 120o, 150o, and 180o. With each shroud, four orientation angles were used; they are 0o, 30o, 60o, and 90o. The experiments were performed under constant cylinder vacuum pressure of 350 mm H2O. The results showed that using shrouded inlet valve increases the swirl number at all valve shroud and orientation angles except for valve shroud angle of 180o and orientation angle of 90o. Also, using of shrouded inlet valve decreases the mass flow rate and the discharge coefficient at all valve shroud and orientation angles.

Swirl generation is an important parameter inside the diesel engine cylinder as it achieves good mixing of air and fuel which has a great influence on the combustion efficiency, engine emissions, and soot formation. The generated swirl intensity by the inlet port and the inlet valve configuration is usually measured on a steady flow test rig using an impulse torque meter. In this paper, an experimental investigation using steady flow test rig was performed on an engine cylinder having a helical-spiral inlet port and shrouded inlet valve. Three valve shrouds were used, they are; 120o, 150o, and 180o. With each shroud, four orientation angles were used; they are 0o, 30o, 60o, and 90o. The experiments were performed under constant cylinder vacuum pressure of 350 mm H2O. The results showed that using shrouded inlet valve increases the swirl number at all valve shroud and orientation angles except for valve shroud angle of 180o and orientation angle of 90o. Also, using of shrouded inlet valve decreases the mass flow rate and the discharge coefficient at all valve shroud and orientation angles.