This paper presents experimentally validated three-dimensional numerical simulation of a 350 kW pilot-scale bubbling fluidized bed combustor, which has been developed by using commercial CFD software package, Fluent 14.5. The solid particle distribution has been simulated by using the multiphase Euler–Euler Approach. The gas–solid momentum exchange coefficients were calculated by...
In the presented work, a model is created in order to investigate the effect of different material parameters and operating conditions on the anode diffusion overpotential, which influence the exergy and energy efficiency of the solid oxide fuel cell (SOFC). In this research, it was demonstrated that the anode material parameters and operating conditions of the device components...
This paper proposes an effective method for very accurate parameter estimation of single- and double-diode solar cell models. For this purpose, unknown parameters of model are estimated by minimization of an objective function using a new highly effective modified version of artificial bee colony (ABC) algorithm. The proposed algorithm is used for parameter estimation of single...
Wind turbines, because of their height and localization, are frequently subject to direct lightning strikes. Thus, the investigation on the performance of their grounding system is of paramount interest for the prediction of the potential threats either for people working in (or animals passing through) the wind farm area and for the power and control units installed in close...
Despite decades of research, the accurate numerical simulation of severely separated flows is still one of the major problems in computational fluid dynamics. In this paper, a viscous-coupled 3D panel method is proposed for the aerodynamic analysis of wind turbine airfoils at high angles of attack. The Hess–Smith panel method is adopted for inviscid calculations, and an...
Tympanotonos fuscatus shell (T. fuscatus shell), an abundant eco-friendly waste was used as a precursor for the production of Tympanotonos fuscatus coagulant (TFC) for the purification of paint effluent (PE). Tympanotonos fuscatus shells (TFS) are of crustacean origin consisting mainly of chitin, calcium carbonate, entrained protein and other organic matrixes. Influence of pH...
This study presents metrics of energy intensity and environmental impact of the back-end separation of ethylene plant consisting three interacting distillation columns by thermodynamic analysis. The objective is to explore the scope of reducing the energy for utilities and CO2 emissions. Thermodynamic analysis is carried out using the column targeting tool (CTT) to address the...
The accuracy of outdoor performance of a photovoltaic (PV) array can be improved by considering the spectral effects. In this paper, the impact of seasonal spectral variations on the three different silicon PV technologies: single junction amorphous silicon (a-Si), Hetero-junction with Intrinsic Thin-layer (HIT) and multi crystalline silicon (mc-Si) has been presented first time...
This article highlights the environmental challenge posed by water hyacinth on fresh water sources in Zimbabwe and investigates the use of the harvested weed as a source of energy in the form of briquettes. The water hyacinth (Eichhornia crassipes), known to be native to South America, has now become an environmental and social challenge throughout most water sources in Zimbabwe...
The effects of antioxidants and storage on oxidation stability of croton biodiesel and its blends with petro-diesel were determined using PetroOxy equipment. The biodiesel and blends were kept in Pyrex reagent bottles and stored in a metallic locker at room temperature for 8 weeks, a condition that imitated ordinary storage environment in tanks before use. The oxidation stability...
This study describes the verification of Wind Atlas Analysis and Application program (WAsP) modelled average wind speeds in a complex terrain. WAsP model was run using data collected at 3 masts: Kalkumpei, Nyiru and Sirima using cup anemometers and wind vanes for the entire 2009 calendar year and verified using data collected by WindTracer LIDAR (light detection and ranging) for...
It is generally accepted that carbon capture and storage strategies will play a crucial role for mitigating CO2 emissions at short- and mid-term scenarios. In this study, a membrane gas absorption process was assessed as potential candidate method for CO2 capture in a Greek brick production industry. The membrane contactor pilot unit was installed near the flue, where a slip...
Pond-grown microalgae have been considered as feedstocks for production of biodiesel. Various natural habitats and man-made environments can be exploited to cultivate microalgae without utilizing arable land which is already decreasing due to urbanization and industrial development. Suitable temperature, solar illumination and availability of phosphorus and nitrogen-rich organic...
The mechanism of the laminar separation bubble and the laminar-turbulent transition over the airfoil UBD5494 is simulated in ANSYS-FLUENT using the transition \({\text{gamma}} - {\text{Re}}_{\theta }\) model at Reynolds number 6 × 104, 1 × 105, 1.5 × 105, 2 × 105 and 3 × 105. Modified constants of the Reynolds momentum thickness are incorporated in the model. The aerodynamic...
The effect of oxygen on the formation of syngas contaminants during the thermochemical conversion of carbonaceous feedstocks has been quantified using an integrated biorefinery plant operated at a biomass input of about 4.5 metric tons/day. This plant combines solids steam reforming and gases steam reforming processes for the conversion of biomass to syngas. It was found that the...
Desalination of water can be achieved via the use of solar stills, especially as they are considered to be the cheapest option for potable water production in remote, arid and small communities with limited availability of freshwater. However, one very common challenge with water production via solar stills is that the amount of water produced is usually low. The aim of this work...
In this paper, a Dish-Stirling Concentrating Solar Power (CSP) system was examined in which the engine works no longer as a receiver but is displaced away from it. In this arrangement it is necessary to adopt a heat transfer fluid capable of transmitting the useful power from the receiver to the hot spring in the Stirling engine head. Various components of the system need...
The present work investigates the potential of different biomasses for air–steam gasification using thermodynamic equilibrium model. A stoichiometric thermodynamic equilibrium model considering char conversion and tar formation is developed using MATLAB software to compare the gasification performance of different biomasses in terms of product gas yield, heating value and energy...
Energy supply security is one of the strategic issues of all states. In Iran, about 35 % of the total energy is consumed by the residential and commercial sectors. According to the importance of residential and commercial sectors in energy consumption, this paper develops different models to analyze energy demand of residential and commercial sectors. The GA and PSO energy demand...
Estimation of the landfill gas (LFG) and electricity potential is one of the significant aspects of an integrated landfill development. In view of this, geological surveys were undertaken in all the government operated landfills in Lagos to appraise ground conditions for the exploitation of the anaerobically generated LFG. Thereafter, attempts were made to estimate the...
In this paper, we present the relative problem of heat and mass transfer to adopt a means of imposing an electromagnetic field to improve solutal segregation (macrosegregation) during liquid metal solidification. A well-validated, quasi-two-dimensional solidifying experimental benchmark was introduced, which allowed us to observe the temperature field evolution and to provide the...
In this study, electric generation capacity of a hydropower system was evaluated through computational fluid dynamics (CFD) modeling and simulation. Performance of paddle wheels in producing hydropower out of running water under different speeds was evaluated, and effects of side and bottom fins and paddle wheel shape on power generation were discussed based on the CFD results...
Currently, the most balanced technical solution for sun protection of glazed areas is the Venetian blind, because it prevents the entry of direct solar radiation, but at the same time provides a view of the outside and allows light to diffuse into the building. The current challenge is to find an improved, integrated technical solution at an affordable cost that requires low...
A novel solar-two-step thermochemical concept for continuous production of H\(_2\) or CO from solar energy and H\(_2\)O or CO\(_2\) using the redox pair MOFe\(_2\)O\(_3\)/MO as reactive particles is proposed and assessed. Here, an efficient continuous separation mechanism is devised by the use of an external magnetic field and the weak magnetization of MOFe\(_2\)O\(_3\) at the...