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[en] Rising concern about energy resource availability and energy prices in Jordan, cost of energy has become an issue that cannot be ignored in Jordan's industrial sector. In this study, energy auditing in a meat production factory related to poultry company was carried out. Based on the collected data and the conservation laws of energy, the performance of steam boilers, domestic hot water boilers, compressors, refrigeration systems, chillers, pumps, daily consumption of diesel and water were reviewed. The percentage of energy consumed by the refrigeration units, with respect to the total energy consumed, has been estimated. The results demonstrated a normal operation with thermal efficiency of 80.66% for the steam boiler, ability to save 18818.99 JD by installing economizer with payback period of 0.637 year and a 12.3% reduction of the energy cost achieved by reducing the blow down rate. The rate of diesel consumption was reduced by 12.87% over the last period of the study as a result of the recommendations that have been submitted to the technicians and professionals. The sum of 22223.77 JD can be saved by using heavy fuel oil instead of diesel oil. Moreover, this study demonstrated that energy saving can be considered as an ideal choice to increase profit and promote competition within the poultry industry if the company adopts all the proposals and recommendations that have been offered by this study.
[en] Sustainable energy generation is becoming increasingly important due to the expected limitations in current energy resources and to reduce pollution. Wave energy generation has seen significant development in recent years. This paper describes an innovative system for generating energy from wave power. A complete description of the system is presented including the general concept, configurations, mechanical design, electrical system, simulation techniques and expected power output of the system. The results from the hydraulic linear wave simulator, using a real wave profiles captured at a location in the UK using an ultrasound system, it was seen that a ±0.8 m wave at 10 s time period, produced a conditioned power output of approximately 22 kW at optimum load conditions for the tested 3-phase 44 kW permanent magnet generator type STK500. The results indicate that this new technology could provide an efficient and low cost method of generating electricity from waves.
[en] Nuclear energy is attracting new interest around the world as countries look for low-carbon alternatives to fossil fuels to increase the diversity of their sources of energy and improve security of supply. Nuclear fission reactors provided approximately one sixth of the world's electricity needs in recent years. The vast majority of these reactors were built in the seventies and eighties. They are thus considered second generation systems, as they are based on experience gained with the first generation or prototypes built in the fifties and early sixties. Third generation reactors, developed in the nineties, are already a reality and will dominate the market in the coming decades. A significant research effort is underway on systems of the fourth generation. Better economics, improved use of natural resources, less production of radioactive waste, competitive production of hydrogen, and increased resistance to proliferation are within reach with these new systems. A review will be done on the most important features of third and fourth generation systems, together with a brief overview of the R and D challenges to be met.
[en] This paper reports the feasibility analysis of co-fired combined cycles (biomass-derived gas + natural gas) based on the gasification of sugarcane residues (bagasse and trash). Performance results are based on simulation of co-fired combined cycles. Feasibility analysis is based on estimates of the capital costs and O and M costs for such cycles, taking into account current and middle term costs of BIG-CC technology (both considering scaling and learning effects). A deep reduction of the investments regarding the gasification island and auxiliaries is a key point to make BIG-CC competitive in the electricity market, and the required learning can be reached with co-fired BIG-CC systems. Besides alleviation of technical problems related to gas turbine operation with biomass-derived gas, co-fired BIG-CC units can operate with relative flexibility regarding the fuel mix. The construction of 10-15 short- to medium-size gasification islands would be enough to induce important cost reductions due to learning effects. As long as the investment on the gasification island is reduced, and depending on the price ratio of natural gas and biomass, pure BIG-CC plants could achieve a reasonable level of feasibility regarding other options of electricity production. In the short run there is no advantage for co-fired combined cycles regarding the costs of reduction of carbon dioxide emissions, but in the middle run both co-fired and pure BIG-CC power plants can be a better option than capture and storage of CO2
[en] The spallation process is a cascade of nuclear reactions induced by medium-energy hadrons, notably protons, which impinge in a suitable material as accelerated particles. A main outcome of that cascade is a shower of medium and high-energy neutrons, which can be used for irradiation purposes or to feed a subcritical reactor. The neutron production is accompanied by the generation of a broad set of radioactive products, which presents specific problems of radiological protection and decay heat removal. The nominal heat load is another point of concern, because of the very high power densities produced in the proton beam energy deposition in the interaction region. All these phenomena are taken into account in this paper in order to set up an integral and coherent task flowchart in order to guide the design of spallation sources
[en] Particle swarm optimization (PSO) algorithm is population-based heuristic global search algorithm inspired by social behavior patterns of organisms that live and interact within large groups. The PSO is based on researches on swarms such as fish schooling and bird flocking. Inspired by the classical PSO method and quantum mechanics theories, this work presents a quantum-inspired version of the PSO (QPSO) using the harmonic oscillator potential well (HQPSO) to solve economic dispatch problems. A 13-units test system with incremental fuel cost function that takes into account the valve-point loading effects is used to illustrate the effectiveness of the proposed HQPSO method compared with the simulation results based on the classical PSO, the QPSO, and other optimization algorithms reported in the literature
[en] Based on the experimental results of R417A flowing inside horizontal microfin tubes, the present work deals with the development of prediction methods for evaporation heat transfer of refrigerant mixtures in microfin tube. The microfin model by Thome et al. is modified by adjusting the convective heat transfer term, and the other microfin model is developed by introducing the enhancement factor into the modified-Kattan model. The comparison of the calculations by several microfin models and the experimental results reveals that the new microfin models developed at the present study are in much better agreement with the experimental results with the reducing average deviation by 30-50% than the models by Thome et al. and Cavallini et al., and are recommended for the prediction of evaporation heat transfer coefficients for non-azeotropic refrigerant mixtures inside microfin tubes
[en] A numerical study of mixed convection from a trapezoidal cavity is carried out. Two openings are adjusted on the plates of the cavity. The inlet opening is horizontal or vertical, while the outlet one is placed horizontally on the bottom wall. The Navier-Stokes equations are solved using a control volume method and the SIMPLEC algorithm is used for the treatment of pressure-velocity coupling. Special emphasis is given to detail the effect of the Reynolds number on the heat transfer generated by mixed convection. The results are given for the parameters of control as, Rayleigh number (Ra = 105), Prandtl number (Pr = 0.72), the inlet and outlet opening width are respectively (C1 = 0.38 and C2 = 0.25), the inclination of the tilted wall (θ = 22 deg. ) and Reynolds number (10 ≤ Re ≤ 1000). The results show that the flow structure and the heat transfer depends significantly on the inlet opening site. Two principal kinds of the problem solution are raised
[en] The evolution of strong surface deformation of a thin viscous fluid layer on a horizontal solid wettable substrate was studied experimentally. Layer deformation is caused by the concentration gradient of surface tension generated by a drop of soluble surfactant placed on the free layer surface. The conditions leading to the layer rupture and drying of the bottom section under the spreading drop were studied. The dependence of the dry spot radius on time, horizontal dimension and thickness of the layer, volume of the introduced droplet and fluids properties, were obtained for various fluid pairs. It was found that the critical initial thickness of the layer, at which its deformation reaches the layer bottom, is practically insensitive to the quantity of the applied surfactant and is defined by the difference in surface tension between the drop and the layer. Comparison of the data with the results of the study of the thermocapillary rupture of a cylindrical layer heated at the center and cooled along the periphery showed good agreement between the dependences of the critical layer thickness on the thermal and the solutal surface tension difference
[en] The present paper deals with the numerical solution of MHD flow and heat transfer outside a stretching cylinder. The governing system of partial differential equations is converted into a system of ordinary differential equations using similarity transformation, which is then solved numerically by the Keller-box method. The effects of the parameters involved, namely the magnetic parameter, Prandtl number and Reynolds number on the velocity and temperature fields are thoroughly examined