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The most diverse fuels in different state among the most common are wood, coal, hydrocarbons (methane CH4, propane C3H8, gasoline, gas oil, kerosene, fuel oil ...), hydrogen (H2). The oxidizer is most often oxygen from the air, more exceptionally pure oxygen (rocket engine, some industrial furnaces) which allows reaching higher temperatures but poses safety problems. Combustion is one of the main themes of energy. This paper study a numerical simulation of combusting hydrogen and various hydrocarbons with air in a burner and the numerical solution of the local entropy generation rate due to the high temperature and velocity gradients in the combustion chamber. In this work the calculations showed that the maximum reaction rates reduce with the augment of φ or the reduce of the oxygen percentage. The temperatures gradients take place in the axial direction, however, the raise of φ considerably minimize them also the increase of φ from 0.5 to 1.0 decrease the entropy generation rates.

In last decades environment has suffered strong and negative consequences resulted by a massive consuming fossil energy. As a result of this process, bioenergy has been intensively increased in recent years. Transportation sector has the largest impact in the use of bioenergy and bioethanol is a type of biofuel which can easily used for transports in place of traditional fossil fuels. Bioethanol production from 1st generation biomass such as corn, sugarcane, has been already commercialized but it is usually not sustainable because it could be seriously damage the food supply. For this reason scientific community has turned his interest to second generation bioethanol from specific energy crops or cultivation of biomass feedstock whose required land for cultivation cannot be used for food cultivations. The case arboreal lingo-cellulose Arundo donax is an example of the latter group. The present paper deals with a simulation method to optimize the performances of second generation bioethanol production by using Arundo donax as feedstock. The bioethanol production was analyzed by means of a life cycle assessment (LCA). The total energy consumption was calculated thanks to Monte Carlo method. The simulation of this second-generation biomass technology was optimized by considering the reuse of light components and of the energy recovery for the agriculture and industrial process. Thanks to these optimizations it was obtained an Energy Return On Investment (EROI) = 1,52 revealing that this technology may certainly be convenient from the energetic point of view.

The synthetic jets have been identified as a promising technique for various fields of both dynamic fluid and aerodynamics, by using different numerical simulations which recently have been played an important role in their development. In the aim to provide the flow mechanisms by influencing both their visualization and their theoretical analysis provided by the implementation of the different validation code, several passive and active techniques have been studied to explore particularly their characteristics. The present work investigates the performance of the Moving Boundary technique which is one of many different computational tools implemented to reproduce the flow behavior of a 3D synthetic jet. The experimental work is a well stabilized test case used as a CFD benchmark by the CFDVAL 2004 workshop. The main feature of the present work is in use of a moving boundary implemented by use of generating computational mesh at every time step of the unsteady computation. Results are first intended to calibrate versus the measurement in order to be sure that phases are accordance. Several points and lines positions are chosen to compare the averaged velocity components. The preliminary results are encouraging and allow reproducing at least qualitatively the flow behavior animations of the synthetic jet. Nevertheless further improvements have to be added, mainly in grid generation and probably in turbulence model selection. The results given in this paper will be used for validating perspective computational studies to control the boundary layer separation.

This paper summarizes the results of a reservoir evaluation study for the T1 Member of the Takinoue Formation at Tomakomai candidate site for CCS demonstration project in Japan. The Takinoue Formation is modeled with 3D seismic and well data and total of fifty realizations are made by geostatistical method. CO2 injection is simulated with the realizations and it is confirmed that 250,000 ton/year of CO2 can be injected through 3 years injection period and be stored for 1000 years.

This paper presents the design of a semi-automatic device for measuring the variables to calculate the thermal resistance of wall systems of buildings. The device is inspired in the hot plate technique from ASTM C-177. It consists of two units: a heating plate and cold plate. The hot plate was designed inserting a coiled electric resistance in parallel, fed by a power source. The cold side was designed with coiled plate made of stainless steel and water from a chiller circulates through the plate at constant temperature. Measurements will be in steady state and unidirectional flow through the wall. The system has pneumatic electronic mobile units that allow managing wall system samples up to 400 kg weight and up to 30 cm thick walls. The variables to be measured are surface wall temperatures, hot and cold plates, the voltage, and current supply by a power source. Using this information, the thermal resistance of a wall system will be calculated and analyzed.

Heat pump systems can be found in high number of applications. One of these is the production of domestic hot water. This paper presents a quasi-steady state simulation model to predict the performance of a simple air source heat pump water heater (ASHPWH). The mathematical model consists of submodels of the basic system components, namely, evaporator, condenser, compressor, and expansion valve. These submodels were built based on fundamental principles of heat transfer and thermodynamics. The model was coded into MATLAB software and used to predict system parameters of interest such as hot water temperature, evaporating and condensing pressures, heat rejected in the condenser, electric power input, heating seasonal performance factor, and coefficient of performance.

Pollution, especially groundwater pollution, is one of the major challenges faced by many countries of the world. Using ‘polluter pay’ principle in settling pollution issues, though is not a new practice, is gaining wider acceptance these days. Scientific techniques capable of fixing responsibility of pollution and meeting the evidentiary requirements in a court of law are important in making a polluter pay for the damages he has made to the environment. In certain cases of groundwater pollution, using mathematical models is the only option in identifying the pollution source(s) and its characteristics. Use of numerical groundwater contaminant transport models in predicting pollution source characteristics involve using them repetitively along with an optimization algorithm until the concentrations predicted by the model match the observed concentrations within a margin of error. But, this matching procedure becomes complex as the model time and observation time are rarely the same. This paper proposes a method to match the modeled and observed concentrations for designing a fitness function. Further, it also explains how the source characteristics are decoded from the solution given by the optimization technique. MT3DMS was the contaminant transport model and genetic algorithm was the optimization algorithm used in the study.

Among the various heat transfer enhancement techniques employed in micro channels, the use of wavy micro channels has been gaining popularity. In this study, numerical heat transfer analysis of wavy micro channels of different cross sections has been conducted by varying the Reynolds number and the amplitude of waviness. Four different cross sections, namely rectangular, circular, notched rectangular and notched circular have been considered in this study. The Reynolds number has been varied from 100 to 800. A three dimensional, steady state numerical heat transfer analysis has been conducted on these channels using the finite volume method. The results indicate that the heat transfer coefficient increases by increasing the amplitude of waviness due to enhancement in fluid mixing. It has been concluded that the notched circular cross section with wave amplitude of 200 μm offers the largest heat transfer coefficient and would be effective for use in compact refrigeration and electronic cooling systems. The relationship between the HTC, Reynolds number and amplitude of waviness has been presented in this paper.

Methane hydrate–bearing layers will be disturbed during the production of methane hydrates, which may induce the deformation or settlement of the layers, and the destruction of engineering structures, so it's important to study the mechanical properties of the hydrate-bearing sediments. In this paper, specimens were prepared in which the methane hydrates were in different location of the specimens by a special deposition method in which the methane hydrate was put in the mold separating with the kaolin, the volume of methane hydrate was 40% of the whole volume of the specimen. A series of triaxial shear tests were carried out under different confining pressures of 1.25 MPa, 2.5 MPa, 3.75 MPa and 5 MPa, conditions with temperature of -6 o C and strain rate of 1%/min. The results indicated that the maximum deviator stress of the sediments increased with the declining of the clay of hydrate and the failure strength achieved maximum when the hydrate clay was in the center of the sediments; the failure strength increased with the increasing of the confining pressure in the low confining pressure stage.

This paper examines cost, challenges and possibilities for the development of an integrated CCS transport infrastructure for the power, cement, refinery and steel and iron sectors in six EU member states: Belgium, Czech Republic, Germany, Netherlands, Poland and Slovakia. Input for ramp-up of CCS within the power sector has been provided by Chalmers Electricity Investment model (ELIN) while ramp-up of CCS in the three industry sectors is based on general assumptions. For each country, three types of CCS infrastructure systems have been assessed; for the power sector only, integrated for the power sector and the three industry sectors and finally, for the three industry sectors only. Transport cost has been calculated to range between € 1.0 and € 4.1 per ton CO2 in the power sector and to between € 1.6 and € 15.9 per ton in the industry sector. The low cost systems indicate a favorable distribution of sources and sinks while high cost systems are a result of low volumes and offshore transport requirements. Transport cost in the integrated system ranged from € 1.2 to € 4.5 per ton implying that there seems to be little to gain for the power sector by integrating transport networks with the industry in the countries investigated, simply due to the location of sources and sinks and the fact that captured volumes from the industry sources are usually considerably smaller than captured volumes from power plants. The results reveal that the development of a CCS infrastructure to a large extent will depend on the phase-in of actual capture plants over time. The ownership concentration within the power sector in most of the countries investigated in this report may facilitate the build-up of a large centralized transport infrastructure.

The solid oxide fuel cell (SOFC) is an electrochemical device that converts the chemical energy present in reactant fuels into electrical energy and heat. Such conversion is given by the electrochemical reactions that occur inside the fuel cells when the reactant gases reach the so-called Three-phase Boundary (TPB). However, before the reactant gases can reach the TPBs, they have to pass through an anisotropic layered material in which the fluid behavior is not easy to explain. The purpose of this paper is to obtain a detailed behavior of the fluid flow through a modeled SOFC anode with gradient porosity using the Lattice Boltzmann method (LBM). Three different modeled SOFC anodes are analyzed keeping the porosity as a constant value, but varying the void space distribution in the flow direction. Results show that the an decreasing porosity in the flow direction can offer more possibilities for reactant gases to get easily the TPB; and therefore, the reaction rate during the electrochemical reactions can be increased.

In this paper, a proposed design for an AC solar micro power generator is introduced. The principle of operation is based on double conversion of incident solar energy to mechanical energy to electrical energy by exciting a Bilayer microcantilever composed of semiconductor and metal to induce electronic stress. The Bilayer microcantilever deflection is used to chop the incident solar energy to produce mechanical oscillation. The produced mechanical oscillation is to be converted to an AC signal using electret-based electrostatic conversion principle. The simulation shows that the obtained electrical AC is in the range from Pico to nano Watt, irrespective of its very low efficiency it is suitable for ultra-low power consuming devices.

In the last years efforts were made to overcome the widespread screen printing metallization technique to reduce shading of the front side, increase the finger conductivity, and improve the contact properties of the metallization of crystalline silicon solar cells. A promising approach is plating via wet chemical metal deposition. Hereby, the metals nickel as contact layer and copper or silver as conduction layer are alternatives to the thick film screen printing process. One challenge using this technique is to avoid the unwanted background plating where the metal is not only deposited on the opened emitter structures but also partly on the isolating surface of the silicon nitride layer.In this paper a detailed overview of the origin of background plating is given, documented by scanning electron microscope pictures. By cutting a groove in the surface of the sample and milling the unwanted metallization as well as the silicon underneath in 12.5 nm steps with a focused gallium ion beam, it was possible to investigate the cross sections by EDX and reveal different origins for the background plating behavior.

In this paper, pure PEI and PEI/Starch thin film sensors were fabricated to detect carbon dioxide (CO2). Films were characterized by ultraviolet-visible spectroscopy (UV–Vis). The quartz crystal microbalance sensors (QCM), coated with the two selected films by the spin-coating method, showed good sensitivities to CO2 gas with concentrations in the range (0.1%-0.5%) at room temperature. In addition, the dependence of temperature on the properties of sensors was studied. It was found that the polyethyleneimine (PEI)/Starch nanocomposite thin film sensor exhibited a better CO2-sensing property than that of a pure polyethyleneimine (PEI) thin film sensor.

The hybrid powertrain is one of the most important technologies that have been developed to satisfy the challenging of fuel economy and emission standards. In recent studies, various types of hybrid vehicles have been proposed. As is well known, a suitable configuration should not only meet the requirements of vehicle kinematics and dynamics, but also meet the requirement of fuel economy and emission. In this paper, the hybrid powertrain system is regarded as a system with multiple power sources. Also, a systematic design and analysis method is proposed, which is based on kinematic degree of freedom and static degree of freedom. The method proposed in this paper provides a new viewpoint for the configuration design and analysis of hybrid power system.

The number of tall buildings is increasing as a result of the advances in construction technologies and the rising land prices. These buildings are characterised by their high energy consumption compared to other building types as they rely intensively on mechanical HVAC systems due to the extreme weather conditions associated with the increase in height. However, they present a great opportunity for energy savings. In recent years, it has been noticed the increasing interest in geometry and form of tall buildings, as a result of the evolution of parametric modelling and 3D visualisation tools, on the expense of the environmental aspect. This paper discusses factors affecting the energy consumption in the tall buildings. Through an extensive analysis of Literature, active and passive energy efficient strategies adopted in tall building at various building stages are identified. In addition, the role of architectural design parameters, such as building form, orientation and envelope on the tall building energy performance are highlighted. Finally, a set of guidelines and environmental design strategies to be considered in different phases in order to achieve energy-efficient tall buildings are proposed. These strategies have been categorised into four stages namely early design, conceptualisation, and documentation and operational. A 3D modelling approach was used to visualise and illustrate the proposed strategies in different stages.

In order to gain advantage in the competition for talent, private enterprises have to create an enabling strategy to attract and retain talent, which is employer brand strategy. The paper defines the meaning of employer brand, and then from the actual situation of private enterprises, it explores methods for private companies to build employer brand in order to establish a good image of employer brand, attract and retain talent, and can give some guidance for companies’ sustainable development.

This paper presents the power quality assessment carried out by an experimental analysis of a real AC/DC hybrid micro grid. Voltage variations and the harmonic issues in both AC and DC voltage are analyzed under “on-grid” and “off-grid” mode operation. The results obtained are then compared with the related Chinese national or IEC standard power network compatibility levels. Besides, the equivalent dynamic impedance of battery converter has also been calculated based on the measured data.

Achieving independence from fossil fuels and reducing emissions by increasing energy efficiency and utilizing green vehicles, such as hybrid electric vehicles and alternative green fuels, are among the main goals of energy policies globally. Although electric cars were introduced many years ago, agricultural electric vehicles have recently gained attention. Beyond emissions reductions, the benefits of agricultural electric vehicles include precise control, continuous variable speeds, and overload capability functionality. Moreover, such technology paves the way for the emergence of autonomous connected vehicles, which enhance work quality and increase operator comfort. Along with the electrification of agricultural vehicles, on-site production of renewable energy to supply their required power enhances the benefits in terms of increased efficiency and energy independence as a future-oriented approach. This paper outlines the trends in development and future perspectives of autonomous farm vehicles premised on green energies, with on-site energy production as a byproduct.

Since the ambient temperature and solar irradiance are not constant, and the P-V characteristic curve of a photovoltaic (PV) module is nonlinear, it is hard for a photovoltaic system to operate at the maximum power point (MPP). In fact, using a maximum power point tracking algorithm (MPPT) to reach the MPP is significant when the climatic conditions change during the day. This paper presents a novel approach for grid-connected PV systems based on a Practical Swarm Optimization (PSO) metaheuristic algorithm to ensure the MPPT functionality as well as generating the reference power for the DC-Bus voltage regulation. The proposed method is compared with the conventional MPPT method Perturb and Observe (P&O) under different irradiance variations. The three-phase, two-level voltage source inverter (VSI) is controlled by a finite set model predictive controller (FS-MPC). The simulation results show that the proposed system is more efficient than the conventional method and has good dynamic performances.

This paper deals with site selection problems for hydrogen production plants and aims to propose a structural procedure for determining the most feasible sites. The study area is Adrar province, Algeria which has a promising wind potential. The methodology is mainly composed of two stages: the first stage is to evaluate and select the best locations for wind-powered hydrogen production using GIS and MCDM technique. the AHP is applied to weigh the criteria and compute a LSI to evaluate potential sites, and the second stage is applying different filtration constraints to select the suitable petrol stations for such hydrogen refueling station modification. The result map showed that the entire Adrar province is almost suitable for wind-powered hydrogen production with varying suitability index. The LSI model groups sites into three categories: High suitable areas, Medium suitable areas, and Low suitable. As a result, 2.95 % (12808.97 km2) of the study area has high suitability, 54.59 % (236320.16 km2) has medium suitability, 1.12 %(4842.94 km2) has low suitability and 41.34 % (178950.35 km2) of the study area is not suitable for wind hydrogen production. By applying the constraints, about 4 stations are suitable for wind-powered hydrogen refueling system retrofitting in Adrar province.

Over the past decades, meta-heuristic optimization techniques have become surprisingly very popular due to their flexibility and local optima avoidance capability. This paper uses the Whale Optimization Algorithm (WOA), a swarm-based technique to tune the Proportional-Integral (PI) based Maximum Power Point Tracking (MPPT) controllers of a grid-connected solar Photovoltaic (PV) system. The results of the PI-based Incremental Conductance (IC) MPPT technique are compared with both the conventional incremental conductance and the Perturb & Observe (P&O) MPPT techniques. Various modes of the PI controller are used. I, PI and Fractional order PI (FOPI) gain parameters are determined using WOA. Performance indices are applied to estimate the best parameters of the PI controller. This paper aims to show the effect of using PI-based MPPT controllers on enhancing the performance of a 400-kW grid-connected PV system. Simulation results show the capability of PI-based MPPT controllers on improving the performance of the PV system. It demonstrates the superiority of FOPI controllers over the other modes in enhancing system performance. The proposed work is simulated using MATLAB SIMULINK.

The intensive energy requirements, the mismatch between the energy supply and demand and the nocturnal temperature drops are all crucial issues in the greenhouses solar heating. This paper seeks to evaluate the effect of a solar air heater with thermal latent storage on the greenhouse microclimate by pursuing the evolution of the internal climate before and after the heating. In this context, an experimental hydroponic greenhouse (HYDGR) and a solar air heater (SAHLSE) were realized in the Thermal Processes Laboratory in the Research and Technology Center of Energy of Borj Cedria in Tunisia. The solar heating with thermal energy storage enhanced the microclimate of the greenhouse and the temperature didn’t drop less than 32 and 15°C respectively the day and at night. The realized solar collector with thermal latent storage offered higher temperature even when the sun is unavailable and increased the internal temperature by more than 5°C. The studied solar system realized good improvement in the hydroponic greenhouse and appeared to be a beneficial alternative for ensuring optimal microclimate.

In this paper, a new design to enhance the thermal performance of residential water heaters is suggested and investigated. The new design consists of using a mixer inside the water tank driven by electrical power. To proceed, experimental measurements are made by using thermocouples implemented in a water heater to study the thermal behavior. It is proved that the mixer could reduce the heating time about 20 min to heat water from 25 °C to 70 °C. In addition, the temperature homogeneity is also studied and it was shown that the temperature without the mixer could not be homogeneous within the water volume.

In recent years, net zero or plus-energy buildings (PEB) have been widely analyzed and discussed for their benefits of increasing energy savings and reducing greenhouse gas emissions. A successful transition to energy-efficient buildings must, however, develop an efficient method that examines technical, economic, environmental and social criteria. In this paper, a method for design optimization based on spatial analysis combined with multi-criteria decision-making was proposed for achieving plus-energy buildings in Algeria. To apply the proposed method, a single family residential building was chosen. First, the annual energy consumption of the building at 40 locations was evaluated and the results are then interpolated for the whole country. The best energy efficiency measures and renewable energy are then chosen using the Analytic Hierarchy Process (AHP) method. Finally, energy balance and spatial analysis were carried out based on the geographical information system. The results showed the energy plus target was achieved in large parts of the country using a high-performance envelope, more efficient appliances and solar energy (solar photovoltaic and thermal). In addition, the southern provinces, mainly Adrar, Tindouf, Bechar, Ouargla, and Illizi, have identified the most suitable areas for setting up new buildings with an energy-plus target. In addition, applying the method will reduce the overall energy demand by 43 % and reduce GHG emissions in the country by around 23 % by 2030. Therefore, the method will have a significant impact on sustainability locally and worldwide.

Magneto-convection heat transfer mode inside a partially open-ended 2D enclosure, which is filled with conducting fluid, is considered as suitable research model in order to scope out our understanding into frequent decisive practicable applications in sustainable and renewable energy domains, especially solar energy collectors. Nevertheless surprising, continuously there is no existing literature dealing with it. Further, for Computational Fluid Dynamics (CFD)’s approaches, it is a considerable defiance to predict and anticipate this coupled complex physical engineering problem in MagnetoHydroDynamic (MHD) configurations. In the current numerical prototype, we introduce the lattice Boltzmann method (LBM) in the aim to overcome such engineering simulation difficulty. It is to be noted that this mesoscopic approach becomes nowadays an essential attractive and alternative for CFD approaches to simulate complex numerous fluid flow problems. ) has become an alternative and attractive approach to simulate numerous fluid flow problems. This paper intends to provide a brief review of researches on application of MHD convection with LBM on the prediction of thermodynamic behavior identifying more opportunities for future research. Besides, some new results are highlighted within this paper. To begin, the present LB model is validated against existing benchmark tests in literature. With the handout of this in house Fortran 90 LB code, we investigate the effects of Hartmann number, Rayleigh number, Prandtl number and the position of the partially open-ended side in the magneto-convective partially open ended y filled with conducting fluid cavity primly. It is established that these elements all impact flow and temperature fields patterns significantly. The obtained results can serve crucial theoretical prototypes for the related future practical magneto-convective applications. Our finding will be a useful tool allowing identifying opportunities for future research related to the considered engineering area.

This paper deals with fractional multi-input, multi-output systems which guarantees a very small number of parameters that can reduce the computation time. It focuses in particular on the state-space representation of systems which highlights the state variables and allows to study the internal behavior with taking into account the initial state. It also discusses the discretization of this type of system to finally adapt the Robust Model Predictive Control (RMPC) to apply it and show its efficiency and performance in these systems.

This paper aims to investigate the possibility of integration of Electric Vehicles EVs supply’s with electricity and/or hydrogen in the road transport sector and estimate the energy supply derived from solar irradiation by using solar roads technology. The case study is road Est-Oust (road E-O) of Algeria. A Geographic Information System and spatial analysis tools are combined with spatial data and technical models to carry out these calculations. The results of this study demonstrate that solar road panels, which are integrated into the road E-O, produce over to 804 GWh/year which equivalents to 13778 tons of hydrogen per year.by using FCEVs will saving over then 41.103 liter of fossil fuels (regular gasoline); and reduce GHG emission (CO2) in the transportation sector by 216 tons per year.

The work in this paper revolves fundamentally around the main axes of fuzzy control of the type Takagi-Sugeno (T-S) zero order for dynamic, complex nonlinear systems. In this paper, we present method for designing Fuzzy controller rule base using a new swarm intelligence algorithm, which is based on the Bat algorithm. The Bat algorithm is one of the most recent swarm intelligence based algorithms that simulates the intelligent hunting behavior of the bats found in nature. The main objective is to design the fuzzy rule base of fuzzy controller respecting the desired performance. To demonstrate the efficiency of the suggested approach, a control of a Magnetic Ball Suspension System is selected. Simulation results shows that the proposed approach could be employed as a simple and effective optimization method for achieving optimum determination of fuzzy rule base parameters.

The classical diagnosis approaches, deeply spread in the industrial environment, are based on the Fourier analysis of the steady-state current, the basis of the proposed methodology consist of analysing the current demanded by the machine during the connection process (startup transient); the objective is to extract the characteristic evolution during the transient of some harmonic components created by the fault; this evolution is caused by the dependence of these components on the slip (s). In this paper the induction motor under dynamic and mixed eccentricity type is modeled with high precision using (CMC) approach.

In this paper, three advanced modelling approaches will be performed to well describe the actual behavior of photovoltaic (PV) cells, in which some total solar irradiance changes are considered. The first one uses a specific solar cell provided by the Sim-Electronics tool of the Matlab software. It is used to simulate the actual behavior of PV cells instead of the conventional electrical circuit based on either single or double diodes. The second approach adopts some physical components provided by the Simscape library to reach the same above mentioned goal. The third approach uses the Simulink blocks to build the mathematical equations describing the PV cell behavior, in which some mathematical operators and functions are used. The three proposed models have the ability to predict the actual behavior of PV cells under different weather conditions. This can improve the extraction of the maximum power and contribute even to the synthesis of the appropriate controller. The performances assessment of each proposed model is established in term of the provided output power as well as the generated current and voltage.