This study presents a numerical assessment of the thermodynamic and environmental performance of a hydrogen-fueled internal combustion engine using a validated zero-dimensional, single-zone model developed in OpenModelica. The engine analyzed is a single-cylinder, four-stroke, spark-ignition unit with direct hydrogen injection, based on a research platform developed at Sandia National Laboratories. The model incorporates essential submodels for engine kinematics, mass and energy balances, gas exchange, combustion heat release, heat transfer, and simplified chemical kinetics. Combustion is represented by the Wiebe function, with its parameters calibrated through comparison with experimentally measured in-cylinder pressure profiles. Initial simulations predict NOₓ emissions of 1.33 g/kWh—exceeding EURO VI regulatory limits. To address this, the study investigates direct water injection (DWI) as an emissions reduction strategy. Results demonstrate that a 10

In this study, we investigate biodiesel extracted from castor oil as an alternative to conventional energy sources. Two significant reasons motivated the exploration of the castor plant. First, castor trees are abundant in southern Algeria, particularly in the El Oued desert. Second, the biodiesel was extracted from castor oil through catalysis with methanol, achieving a yield of around 64

Through energy and exergy analysis, the present work revisits the combustion processes generated using different fuels (CH4, C3H8, H2, LPG, Natural gas and Biogas) under the same operating conditions. First, numerical computations, in which the turbulent dynamic k-& varepsilon; model coupled with a probability density function (PDF) approach together with different sub-models that ensure the reliability of the results, are used. Then, the First and Second Laws of thermodynamics are applied to all fuel combustion cases considered previously to predict the energy loss, exergy destruction and their corresponding efficiencies. Next, variations in the air factor, the air inlet temperature and the fuel inlet temperatures are considered to analyse the response of combustion system performance as well as energy and exergy losses for the different fuels under investigation. The results show an amelioration of combustion parameters for the mixture of fuel and air using values of lambda greater than 1. Also, the preheating of the inlet air temperature has a positive effect on energetic parameters. However, preheating the inlet fuel does not take a considerable role in the efficiency amelioration and loss reduction of the combustion system. It further turns out that biogas features higher energy efficiency compared to other fuels, at approximately 89.64%, while hydrogen fuel exhibits higher exergy efficiency at around 78.70% followed by biogas with 74.96%.

This work aims to demonstrate the feasibility of solar heating of a stand-alone house located in a continental climate region in Algeria. The design and optimisation of this system are based on dynamic simulations of a typical rural house using a TRNSYS-Fortran program. To manage all the subsystems composing the heating system, a pertinent control strategy is adopted. Using 2.8-m3 storage tanks, the optimal solar share in meeting the annual thermal needs of the house is 46%. Besides, an energy-efficient design based on a local bio-composite thermal insulation material reduces the thermal energy needs of the house by 42%. The results of optimisation calculations are compared to experimental tests and show good agreement. For environmental impact, the study reveals that 39% of CO2 emissions can be avoided annually. Moreover, the economic cost of the system has been evaluated, and the results show that the payback period is 53 years.

In the current paper, we illustrate a numerical simulation of the non-premixed combustion in a cylindrical combustor fueled by Methane and/or Hydrogen. The aerothemochemical parameters evolutions that characterize the reacting flow are attested for different fuel compositions in the combustor. For this, the exergy loss and its functional efficiency are applied for all considered fuels to distinguish the optimum reactive mixture composition for economic combustion. Consequently, the calculations are carried out by both computational software FLUENT code package and the Cycle-Tempo Release. Then, the results proved that the hydrogen injection has an effect on all considered physic-chemical variables.

The current paper illustrates the numerical study of the global combustion parameters. It mainly focused on the computational analysis that investigated the non-premixed combustion in the cylindrical burner. Therefore, we selected many fuels to supply the burner like Algerian biogas, CH4, C3H8, H2, natural gas, and diesel to compare their aerothermochemical characteristics variables. At first, we applied the numerical methods that confirm the solution convergence like combustion models and grid selection. After that, we resolved the aerothermochemical set equations of combustion using the coupled k-ɛ turbulent dynamic model with the probability density function approach. These models are also used to surmount the closer in the set of combustion equations too. Moreover, we integrated the pollutant computation model based on the chemical reactions of NO production. Thus, we evaluated each considered fuel’s NO emission during all combustion fuels cases. Accordingly, the results show that Algerian biogas and hydrogen have special characteristics compared to other cases of fuels. The most prominent characteristics are: the high level of the mixture and burn relative to other fuels, their low pollutants emissions (CO and NO), and the proportional relationship between the OH and NO production. Consequently, biogas and H2conserve the impact on energy and the environment.

In this paper, we investigate the exergy analysis of the combustion chamber supplied by different fuel compositions based mainly on methane and/or hydrogen in order to select the optimum fuel composition case for the economic combustion. For this, the analysis process considers the variation for both parameters: mass flow rate and equivalence ratio. This is to characterize all fuel cases. The calculations are based on the prediction of three variables: the exergy destruction and the exergy universal efficiency, the contribution of exergy destruction sources and the effect of fuel composition on these sources. Therefore, all computations of this investigation are carried out by the Cycle-Tempo Release to determine the appropriate fuel composition. In the overall, the obtained results show that the hydrogen enrichment methane flame has an impact on the combustion efficiency.

The paper presents a thermodynamic analysis of an existing ISCC power plant when running at off-design operation conditions. The off-design regime is due to changes in air temperature and DNI. The analysis is based on the results of calculations performed by the flow sheet programme 'Cycle-Tempo'. For off-design modelling, some reasonable assumptions are adopted in regard to the operations of the turbomachines and heat exchangers. The power plant performance is examined when it is running following the operation strategy 'saving mode'. The complementarily between the solar field and the duct burners (DBs), and the operation of the power plant, in terms of hourly net electricity output and thermal efficiency, are analysed on two representative days, a summer day and a winter day. The key parameters in the study are essentially the HTF mass flow rate, DB fuel consumption, thermal energies supplied by the solar field, and the DBs.

The present work investigates the energy and exergy analysis for some fuels supplied the cylindrical combustion chamber. Indeed, this work is focused on the comparison of the different carbon based fuels to the H2 fuel as a reference case. After that, the energy and exergy analysis are applied for all fuels compositions, in order to select the fuel corresponding to the optimum combustion for the considered burner in this work. The computations are performed with the use of the Cycle-Tempo Release package code. Finely, the obtained results in this study illustrate that the hydrogen is the best fuel in the considered configuration.

The present investigation illustrates a computational study of the turbulent diffusion flame in a cylindrical burner that is confined by two coaxial jets (methane/hydrogen and air). This is to improve the reactive mixture, the reactants combustion and to reduce the concentration of carbon monoxide as pollutant chemical species. The coupled models LES/PDF are, hereby, used to surmount the turbulence/chemistry interaction in the transport equations of chemical species. The predicted mixture fraction, the progress variable, and the carbon monoxide mass fraction are selected to validate the coupled models with respect to the experimental references data. Furthermore, the same scalar parameters which are considered in the previous numerical validation are evaluated from different fuel compositions of the hydrogen and the methane percentage to supply the combustion chamber. The computed results are carried out by FLUENT-CFD; where, they prove that hydrogen addition reduces the carbon monoxide concentration in the combustion products and improves the reactants combustion caused by the rich mixture.

Solar distillation is a simple method used for the production of drinking water from saline or brackish water. This method proposes a solution for the production of fresh water in arid and desert areas, where a large solar field is available and also the existence of underground sources of saline water. A solar distiller with a single basin and double slopes is theoretically examined. The theoretical model is based on the resolution of equations of heat and mass transfer dependent on time for glazing cover, water film and absorber basin. For validating the results of the theoretical model, a comparison with the experimental results was carried out. A series of experimental tests on a solar distiller with double slopes in the climatic conditions of Ouargla in Algeria were performed. The tests were carried out on 19th February 2009. The amount of water distilled was 2.7 liters, after a day's work. The results show that the cooling of the glazing cover leads to increase in the amount of distilled water of about 17% in comparison with the reference case. In addition, we found a good agreement between the results of the theoretical model and the experimental data.

The paper presents a numerical thermal analysis concerning the operation of the solar receiver Schott PTR-70 under the running conditions of Hassi R'Mel power plant. The analysis is based on numerical resolution by finite difference method of a 1D transient modelling of heat transfer balances taking place in the receiver. At first, a modelling validation against experimentally determined correlations issued from NREL facility tests is given. The comparison and confirmation are in terms of thermal efficiency and linear heat loss of the receiver versus HTF average temperature. Then, a discussion is developed about how the production of hot HTF (392 degrees C) varies versus DNI intensity for four typical days each representative of a season? Afterwards, it is concluded that the enhancement of heat convective transfer between the absorber and the HTF would have no positive effect on HTF mass flow rate.

This study presents a numerical investigation of the effects of mixing methane/hydrogen on turbulent combustion processes taking place in a burner similar to that integrated in gas turbine power plants. Thereby, in comparison to the reference case where the burner is fuelled by 100% of methane, the variations of the axial velocity field, temperature field and mass fraction of carbon monoxide field are examined for different percentages of hydrogen fuel injection. The computed results, obtained by using the software Fluent-CFD, are compared and validated against experimental reference data. Results show that the hydrogen addition to the methane has an impact on all physical and chemical parameters of the reactive system.

Thermodynamic irreversibilities generated by the combustion process are evaluated and analyzed numerically. The numerical simulation is performed for a reference case study for which experimental data are available in the literature: diffusion flame properties in a common burner configuration are studied by the Fluent software with the standard k–ε turbulence model and two-step chemical reaction. The study quantifies the contribution of each mechanism to entropy generation, i.e., friction, heat conduction, species diffusion, and chemical reaction. The chemical reaction and heat conduction are found to be the major sources of entropy production. Preheating of air reduces thermodynamic irreversibilities within the combustor.

This study presents a numerical investigation on the proton exchange membrane fuel cell (PEMFC) and the solid oxide fuel cell (SOFC), using the aerothermal and electrochemistry equations to describe all phenomena included in both types of the fuel cells. The computational process is based on the implementation of the mathematical fuel cells models in FLUENT computational fluid dynamics code. This is in order to evaluate the temperature field, the production of the electricity, and the distribution of the water mass fraction in different region of the fuel cells. The obtained results show that the simulation is able to evaluate the physical and chemical parameters to explain the main phenomena in the fuel cells.

This work is focused on the analysis of various computed terms of entropy generation rate in the gaseous combustion processes at different inlet temperatures of air and CH4. Therefore, the expression of the entropy generation rate includes the effect of the viscosity friction, the thermal diffusion, the species diffusion and the chemical reaction. The expressions have been used for each term of entropy generation in order to examine the influence of each one in the overall system.

In this work, we present a computational study of the turbulent diffusion flame in cylindrical combustor confined by two coaxial jets (Methane/Hydrogen and Air), in order to improve the reactive mixture, the reactants combustion and to reduce the carbon monoxide as pollutant chemical specie. Hereby, the coupled models LES/PDF are used to surmount the turbulence/chemistry interaction in the transport equations of chemical species. Whereas, the predict mixture fraction, the progress variable and the carbon monoxide mass fraction are selected to validate with the experimental references data. Furthermore, the same scalar parameters which are considered in the previous numerical validation are evaluated from different fuel compositions of the hydrogen and the methane percentage to supply the combustion chamber. The hydrogen addition reduces the carbon monoxide in the combustion products and improves the reactants burn caused by the rich mixture.