scholarly journals Exergetic analysis of a dual-fuel engine, PEM electrolyzer and thermoelectric generator integrated system

DYNA ◽  
2020 ◽  
Vol 87 (215) ◽  
pp. 66-75
Author(s):  
Nelly De Armas Calderón ◽  
Cristina Lizarazo Bohórquez ◽  
Jorge Duarte Forero
Keyword(s):  
Thermoelectric Generator ◽  
Combustion Engine ◽  
Integrated System ◽  
Operating Conditions ◽  
Dual Fuel ◽  
Inlet Temperature ◽  
Exergetic Efficiency ◽  
Pem Electrolyzer ◽  
Exergetic Analysis ◽  
A Current

In this research, the implementation of an integrated system composed of a dual-fuel engine (Diesel-Hydrogen), a PEM electrolyzer and a thermoelectric generator is envisioned. In order to know the optimal operating conditions of each sub-system, the exergetic efficiency and destroyed exergy were studied. It was estimated that for the dual combustion engine, the destroyed exergy would increase as a function of the concentration of methane in its mixture. By varying the electrical input to the electrolyzer, it was found that when the input current was 2A, the exergetic efficiency would go up to 92.59%, while for a current of 5A, the efficiency decreased in 51.80%. Finally, the exergetic efficiency of TEG decreased by increasing the hot flow temperature; 86.68% of the decrease in efficiency occurred for temperatures between 470K and 510K. On the other hand, the destroyed exergy increased linearly with an increase in the inlet temperature of exhaust gases.

scholarly journals Closed-loop control of a dual-fuel engine working with different combustion modes using in-cylinder pressure feedback

2019 ◽  
Vol 21 (3) ◽  
pp. 484-496 ◽  
Author(s):  
Carlos Guardiola ◽  
Benjamín Pla ◽  
Pau Bares ◽  
Alvin Barbier
Keyword(s):  
Closed Loop ◽  
Combustion Engine ◽  
Fuel Combustion ◽  
Operating Conditions ◽  
Dual Fuel ◽  
Maximum Pressure ◽  
Cylinder Pressure ◽  
Pressure Derivative ◽  
Combustion Modes ◽  
Dual Fuel Combustion

This work presents a closed-loop combustion control concept using in-cylinder pressure as a feedback in a dual-fuel combustion engine. At low load, reactivity controlled compression ignition combustion was used while a diffusive dual-fuel combustion was performed at higher loads. The aim of the presented controller is to maintain the indicated mean effective pressure and the combustion phasing at a target value, and to keep the maximum pressure derivative under a limit to avoid engine damage in all the combustion modes by cyclically adapting the injection settings. Various tests were performed at steady-state conditions showing good abilities to fulfil the expected operating conditions but also to reject disturbances such as intake pressure or exhaust gas recirculation variations. Finally, the proposed control strategy was tested during a load transient resulting in a combustion switching-mode and the results exhibited the closed-loop potential for controlling such combustion concept.

Behavior Prediction Model in Gas Fueled Spark Ignition Internal Combustion Engines Turbocharged for Genset Application

2013 ◽  
Author(s):  
Jorge Duarte Forero ◽  
German Amador Diaz ◽  
Fabio Blanco Castillo ◽  
Lesme Corredor Martinez ◽  
Ricardo Vasquez Padilla
Keyword(s):  
Equivalence Ratio ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Inlet Temperature ◽  
Combustion Engines ◽  
Gaseous Fuels ◽  
Methane Number

In this paper, a mathematical model is performed in order to analyze the effect of the methane number (MN) on knock tendency when spark ignition internal combustion engine operate with gaseous fuels produced from different thermochemical processes. The model was validated with experimental data reported in literature and the results were satisfactory. A general correlation for estimating the autoignition time of gaseous fuels in function of cylinder temperature, and pressure, equivalence ratio and methane number of the fuel was carried out. Livengood and Wu correlation is used to predict autoignition in function of the crank angle. This criterium is a way to predict the autoignition tendency of a fuel/air mixture under engine conditions and consider the ignition delay. A chemical equilibrium model which considers 98 chemical species was used in this research in order to simulate the combustion of the gaseous fuels at differents engine operating conditions. The effect of spark advance, equivalence ratio, methane number (MN), charge (inlet pressure) and inlet temperature (manifold temperature) on engine knocking is evaluated. This work, explore the feasibility of using syngas with low methane number as fuel for commercial internal combustion engines.

scholarly journals Numerical Performance Investigation of Parabolic Dish Solar-Assisted Cogeneration Plant Using Different Heat Transfer Fluids

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Muhammad Sajid Khan ◽  
Muhammad Abid ◽  
Khuram Pervez Amber ◽  
Hafiz Muhammad Ali ◽  
Mi Yan ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Solar Collector ◽  
Integrated System ◽  
Operating Conditions ◽  
Heat Transfer Fluid ◽  
Working Fluid ◽  
Inlet Temperature ◽  
Pressurized Water ◽  
Parabolic Dish ◽  
Process Heating

Parabolic dish solar collectors gain higher solar to thermal conversion efficiency due to their maximum concentration ratio. The present research focuses by integrating the parabolic dish solar collector to the steam cycle producing power and rate of process heating. Pressurized water, therminol VP1, and supercritical carbon dioxide are the examined working fluids in the parabolic dish solar collector. The aim of the current research is to observe the optimal operating conditions for each heat transfer fluid by varying inlet temperature and flow rate of the working fluid in the parabolic dish solar collector, and combination of these parameters is predicted to lead to the maximum energy and exergy efficiencies of the collector. The operating parameters are varied to investigate the overall system efficiencies, work output, and process heating rate. Findings of the study declare that water is an efficient heat transfer fluid at low temperature levels, whereas therminol VP1 is effective for a higher temperature range. The integrated system efficiencies are higher at maximum flow rates and low inlet temperatures. The efficiency map of solar collector is located at the end of study, and it shows that maximum exergy efficiency gains at inlet temperature of 750 K and it is observed to be 37.75%.

Parametric Effects on Exergetic Efficiency During H2-O2 Combustion Including Singlet Oxygen

2014 ◽  
Author(s):  
DeVon A. Washington ◽  
Howard N. Shapiro
Keyword(s):  
Singlet Oxygen ◽  
Ignition Temperature ◽  
Equivalence Ratio ◽  
Flow Reactor ◽  
Operating Conditions ◽  
Inlet Temperature ◽  
Exergy Destruction ◽  
Exergetic Efficiency ◽  
Inlet Concentration ◽  
Optimal Range

Previous work conducted by the authors showed that for a stoichiometric inlet fuel-oxidizer ratio at 1 atm and 1200 K, an optimal range of exergetic efficiency exists for H2 combustion when singlet oxygen composes 0–20% of the oxidizer; with the maximum occurring at approximately 10%. Additionally, in the optimal range, 60% of the total exergy destruction occurs before ignition. These results provide encouraging evidence that it is possible to improve the exergetic efficiency of combustion inherently and thereby reduce fuel usage for a desired energy transfer. The focus of this study is to determine if the exergetic efficiency of combustion can be further optimized by varying other combustion parameters in addition to the inlet concentration of singlet oxygen. The chemical kinetics simulation was accomplished by developing an adiabatic plug flow reactor model in CHEMKIN-PRO® and employing the Moscow State University H2-O2 mechanism. The ranges of parameters considered were: equivalence ratio 0.7–1.3, inlet temperature 1100–1300 K, inlet concentration of singlet oxygen 0–20%, and diluent type (Ar, N2, no dilution). Pressure was held fixed at 1 atm. The calculated quantities were: exergetic efficiency, exergy destruction before ignition, molar conversion of H2, exit temperature, ignition temperature, and ignition distance. Results of the study show that over the optimum range the maximum exergetic efficiency occurs for an equivalence ratio of 1.3, with no dilution at 1300 K. Furthermore, the data show that for 20% inlet singlet oxygen there is significant variability in exergy destruction before ignition, ignition temperature, and ignition distance. Understanding how varying traditional combustion parameters impacts the enhancing effect that singlet oxygen has on the exergetic efficiency of H2 combustion provides a framework for directing future research efforts for hydrocarbon combustion under a broader range of operating conditions of practical engineering interest.

Analysis of a Dual-Fuel Combustion Engine Fueled with Diesel Fuel and CNG in Transient Operating Conditions

2016 ◽  
Author(s):  
Ireneusz Pielecha ◽  
Krzysztof Wislocki ◽  
Wojciech Cieslik ◽  
Przemyslaw Borowski ◽  
Wojciech Bueschke ◽  
...  
Keyword(s):  
Diesel Fuel ◽  
Combustion Engine ◽  
Fuel Combustion ◽  
Operating Conditions ◽  
Dual Fuel ◽  
Dual Fuel Combustion

scholarly journals Experimental Analysis of Solar Assisted Refrigerating Electric Vehicle

2021 ◽  
Vol 9 (5) ◽  
pp. 305-315
Author(s):  
Surender Kumar ◽  
R.S. Bharj
Keyword(s):  
Electric Vehicle ◽  
Combustion Engine ◽  
Load Condition ◽  
Integrated System ◽  
Operating Conditions ◽  
Maximum Speed ◽  
Hybrid Energy ◽  
Full Load ◽  
Energy Mode ◽  
Battery Bank

Most refrigerating systems are driven by an internal combustion engine that increased the conventional vehicle's oil consumption and tailpipe emissions. The solar-assisted refrigerating electric vehicle (SAREV) system powered by a hybrid energy mode has been designed. The hybrid energy (solar + grid) was stored in the battery bank to complete this vehicle's necessary functions. The PV panels are prominently incorporated into this vehicle rooftop to charge the battery bank. In this study, the integrated system was driven by a hybrid energy mode that reducing the wastage and deterioration during temporary storage and transportation in different areas. The performance of the integrated system was tested under different operating conditions. The effect of load variation on maximum speed and travelling distance of vehicle was analyzed. The battery bank charging and discharge performance were studied with and without solar energy. The refrigerator was consuming 116 Wh energy per day to maintain a -12 oC lower temperature on the no-load condition at the higher thermostat position. The refrigerator was run continuously for 4-6 days on battery bank energy and 7-10 days on the full load condition of hybrid energy. The vehicle was travelling at a maximum of 23 km/h speed on full load condition. The vehicle needed torque 14-16 N-m at the initial phase for each load condition. Torque demand was decreasing with the increasing speed of the vehicle. The full-charged battery bank's initial voltage was 51.04 V, and the cut-off voltage was 46.51 V. The vehicle was covering a distance of 62.4 km with the battery bank alone at full load condition. It was travelling 68.3 km distance with hybrid energy mode. The vehicle's integrated system was the best in maintaining battery performance, power contribution capability, and drive range enhancement.

Modeling and Performance Analysis of an Integrated System: Variable Speed Operated Internal Combustion Engine Combined Heat and Power Unit–Photovoltaic Array

2015 ◽  
Vol 137 (3) ◽  
Author(s):  
Robert Radu ◽  
Diego Micheli ◽  
Stefano Alessandrini ◽  
Iosto Casula ◽  
Bogdan Radu
Keyword(s):  
Internal Combustion Engine ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Combined Heat And Power ◽  
Integrated System ◽  
Operating Conditions ◽  
Variable Speed ◽  
Pv System ◽  
System Variable ◽  
Photovoltaic Array

The paper presents the model of a combined heat and power (CHP) unit, based on a variable speed internal combustion engine (ICE) interfaced with a photovoltaic (PV) system. This model is validated by means of experimental data obtained on an 85 kWe CHP unit fueled with natural gas and a PV system with a rated power of 17.9 kW. Starting from daily load profiles, the model is applied to investigate the primary energy saving (PES) of the integrated CHP + PV system in several operating conditions and for different sizes of PV array. The results demonstrate the dependence of the CHP performance on the operating mode and a limited convenience of the variable speed strategy. The integrated system operation leads to performance improvements, which depend on the size of the PV component.

Unsteady simulations of migration and deposition of fly-ash particles in the first-stage turbine of an aero-engine

2021 ◽  
pp. 1-21
Author(s):  
Z. Hao ◽  
X. Yang ◽  
Z. Feng
Keyword(s):  
Fly Ash ◽  
Film Cooling ◽  
Particle Deposition ◽  
Flow Characteristics ◽  
Leading Edge ◽  
Velocity Model ◽  
Operating Conditions ◽  
Inlet Temperature ◽  
Internal Cooling ◽  
Aero Engine

Abstract Particulate deposits in aero-engine turbines change the profile of blades, increase the blade surface roughness and block internal cooling channels and film cooling holes, which generally leads to the degradation of aerodynamic and cooling performance. To reveal particle deposition effects in the turbine, unsteady simulations were performed by investigating the migration patterns and deposition characteristics of the particle contaminant in a one-stage, high-pressure turbine of an aero-engine. Two typical operating conditions of the aero-engine, i.e. high-temperature take-off and economic cruise, were discussed, and the effects of particle size on the migration and deposition of fly-ash particles were demonstrated. A critical velocity model was applied to predict particle deposition. Comparisons between the stator and rotor were made by presenting the concentration and trajectory of the particles and the resulting deposition patterns on the aerofoil surfaces. Results show that the migration and deposition of the particles in the stator passage is dominated by the flow characteristics of fluid and the property of particles. In the subsequential rotor passage, in addition to these factors, particles are also affected by the stator–rotor interaction and the interference between rotors. With higher inlet temperature and larger diameter of the particle, the quantity of deposits increases and the deposition is distributed mainly on the Pressure Side (PS) and the Leading Edge (LE) of the aerofoil.

scholarly journals Analysis of the Total Unit Energy Consumption of a Car with a Hybrid Drive System in Real Operating Conditions

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3966
Author(s):  
Jarosław Mamala ◽  
Michał Śmieja ◽  
Krzysztof Prażnowski
Keyword(s):  
Energy Consumption ◽  
Internal Combustion Engine ◽  
Electric Drive ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Operating Conditions ◽  
Hybrid Drive ◽  
Total Unit ◽  
Unit Energy ◽  
Unit Energy Consumption

The market demand for vehicles with reduced energy consumption, as well as increasingly stringent standards limiting CO2 emissions, are the focus of a large number of research works undertaken in the analysis of the energy consumption of cars in real operating conditions. Taking into account the growing share of hybrid drive units on the automotive market, the aim of the article is to analyse the total unit energy consumption of a car operating in real road conditions, equipped with an advanced hybrid drive system of the PHEV (plug-in hybrid electric vehicles) type. In this paper, special attention has been paid to the total unit energy consumption of a car resulting from the cooperation of the two independent power units, internal combustion and electric. The results obtained for the individual drive units were presented in the form of a new unit index of the car, which allows us to compare the consumption of energy obtained from fuel with the use of electricity supported from the car’s batteries, during journeys in real road conditions. The presented research results indicate a several-fold increase in the total unit energy consumption of a car powered by an internal combustion engine compared to an electric car. The values of the total unit energy consumption of the car in real road conditions for the internal combustion drive are within the range 1.25–2.95 (J/(kg · m)) in relation to the electric drive 0.27–1.1 (J/(kg · m)) in terms of instantaneous values. In terms of average values, the appropriate values for only the combustion engine are 1.54 (J/(kg · m)) and for the electric drive only are 0.45 (J/(kg · m)) which results in the internal combustion engine values being 3.4 times higher than the electric values. It is the combustion of fuel that causes the greatest increase in energy supplied from the drive unit to the car’s propulsion system in the TTW (tank to wheels) system. At the same time this component is responsible for energy losses and CO2 emissions to the environment. The results were analysed to identify the differences between the actual life cycle energy consumption of the hybrid powertrain and the WLTP (Worldwide Harmonized Light-Duty Test Procedure) homologation cycle.

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