Exhaust Heat Research Articles

System design and thermo-economic analysis of a new coal power generation system based on supercritical water gasification with full CO2 capture

To achieve sustainable energy supply and carbon neutral, it is essential to enhance the efficiency and reduce carbon emissions for coal power. In this study, a coal power generation system based on supercritical water gasification (SCWG) with full CO2 capture is proposed. The system achieves autothermal gasification by partial oxidation of coal in the SCWG gasifier. Gasification water is preheated by turbine exhaust, and organic Rankine cycle (ORC) is integrated to recover the waste heat of turbine exhaust. Simulation and thermodynamic analysis models of the system are developed. Results show the energy efficiency and exergy efficiency of system with benchmark parameters reach 52.95 % and 54.11 %, respectively. The largest exergy destruction occurs in gasifier and accounts for 41.36 % of the total exergy loss. Irreversibility of heat transfer mainly occurs in water heat exchanger and ORC, accounting for 4.81 % and 5.59 % of the total loss. Effects of key operating parameters on the system performance are investigated. Results show the optimal turbine exhaust pressure is 0.1 MPa, and higher turbine inlet temperature can enhance the system efficiency. System with reheat configuration shows potential in thermodynamic and economic aspects, and the exergy efficiency of double reheat system is improved from 37.25 % to 45.08 %.

Influence of N-Butanol-Diesel Fuel Blends on the Performance Characteristics of a Four Stroke, Compression Ignition Engine

Aims: This study investigates the impact of blending n-butanol with diesel fuel on the performance of a single-cylinder, 4-stroke diesel engine under varying engine loads.
 Study design: The performance assessment followed SAE J1349 on a Tec-Quipment TD110-115 4-stroke engine at 1500 rpm with varying loads and fuel samples.
 Place and Duration of Study: The study was conducted for 2 months the at Automotive Engineering Technology Workshop, Federal Polytechnic, Bauchi Nigeria.
 Methodology: The SAE J1349 test protocol was followed, using diesel fuel (D95) and different blended fuel samples (D90, D85, D80, D75, and D70). While diesel fuel generated higher brake power due to its higher calorific value, the D95 blend demonstrated comparable performance to diesel fuel across all parameters.
 Results: The brake power of the D95 blend initially decreased by 69.7% and then increased as the load increased to 2500g and 3000g, indicating improved combustion due to oxygenation. The D95 blend exhibited lower fuel consumption compared to diesel fuel, although blends with higher n-butanol percentages showed increased brake-specific fuel consumption due to lower calorific values, densities, and viscosities. Under maximum load, the D95 blend exhibited higher exhaust gas temperature and heat loss, reflecting the increased fuel quantity required for additional power. Lower heat losses at lower loads were attributed to factors such as lower calorific values, n-butanol's heat of vaporization, temperature differentials between the exhaust and ambient conditions, and engine size.
 Conclusion: The engine load has diverse effects on parameters across different fuel samples. D95 exhibits similar performance to diesel, yet discrepancies arise, especially with higher n-butanol content at lower loads.

Effects of methanol direct injection and high compression ratio on improving the performances of a spark-ignition passenger car engine

The high octane number and high latent heat of vaporization of methanol are beneficial to suppress knock and consequently increase compression ratio (CR) of spark ignition engines, and thus improve the thermal efficiency. Few preious research on methanol engine combuston and performances have been conducted based on spark-ignition passenger car engines with a CR greater than 14. In this study, a 1.5-liter spark ignition passenger car engine with miller cycle was used to explore the potentials of high CR and methanol direct injection (MDI) on improving engine performances. First, the engine was tested under stoichiometric combustion using methanol and gasoline at BMEPs of 1.1 MPa and 1.5 MPa with CR11.5, CR13.8, and CR15.3. Then, the performances of the CR11.5 case with gasoline and the CR15.3 case with methanol were compared under lean burn combustion. The results show that for gasoline, increasing CR from 11.5 to 15.3 results in decreased fuel economy under stoichiometric combustion, whereas the exact opposite tendency is shown for methanol. Integrating a high CR of 15.3 and MDI improves brake thermal efficiency (BTE) to 43.3 % at an excess air/fuel ratio (λ) of 1.0, when compared with 37.4 % of gasoline at CR11.5. Applying lean burn can further improve the BTE of methanol at CR15.3 to 44.9 %. The main causes of the improvement of BTE by high CR and MDI are the reduced exhaust heat loss resulted from earlier combustion phasing. However, high CR and MDI also extend combustion durations at all specified λs, and emit more THC and CO emissions than low CR with gasoline at high λs because of higher surface/volume ratio and flame quenching. The extended combustion duration and the incomplete combustion are the main barriers to greater BTE for MDI sprak ignition engine with high CR.

Experimental Study of the Influences of Operating Parameters on the Performance, Energy and Exergy Characteristics of a Turbocharged Marine Low-Speed Engine

With appropriate strategy of EVC timing and fuel injection, the engine NOx emission could be reduced with acceptable deterioration of fuel consumption. However, for the mechanism of these favorable results, few studies focus on improving the fuel economy from the perspective of energy and exergy analysis, which could be helpful for providing a deeper comprehensive to researchers. Therefore, an experimental study for the combination of EVC timing and fuel injection strategy is conducted based on a marine low-speed engine with 340 mm bore, then the energy and the exergy analysis are separately carried out according to the obtained experimental results. The experimental results show that delaying the exhaust valve closing (EVC), complemented with an appropriate injection strategy, could improve the marine low-speed diesel engine brake specific fuel consumption (BSFC) with the NOx emission almost kept constant. The following energy balance analysis demonstrates that the losses from exhaust gas and heat transfer account for about 50% of total energy. However, from the perspective of exergy analysis, an opposite conclusion could be obtained; the proportion of exhaust gas and heat transfer exergy could reach about 15%, and the ratio of heat transfer could be higher relatively. The losses caused by irreversibility is the biggest source of all, and the irreversibility from combustion could takes about 70% of the total irreversibility. Finally, the reduction of total irreversibility could reach about 4% by optimizing the parameters of marine low-speed engines.

Experimental and kinetic study of methanol reforming and methanol-syngas co-oxidation at high pressure

Using engine exhaust heat to partially convert methanol to syngas and then co-combust is a favored strategy to optimize combustion in methanol engines. In the present work, experiments of methanol pyrolysis and methanol-syngas oxidation were conducted using flow reactors at 1.0–5.0 MPa. The substitution ratio of syngas to methanol varied from 0 to 50%. Experimental results show that high pressure slightly promotes methanol pyrolysis and reduces CH2O generation; syngas inhibits methanol oxidation and reduces CH2O generation. Otherwise, experimental results were used to validate the recently published methanol model, and Mech15.34 captures the experimental data well. The kinetic analysis revealed the effects of substitution ratio on methanol-syngas co-oxidation can be divided into dilution and chemical effects. The dilution effect refers to the reduction of methanol, which directly decreases the CH2O generation. The chemical effect refers to the competition of H2 and CO for OH radicals, which decelerates the CH3OH oxidation. Meanwhile, the reaction H2O2 + H = H2 + HO2 proceeds in reverse direction with H2 blending, generating more H radicals, which enhances the CH2O consumption through the reaction CH2O + H = HCO + H2.

Integration of a Gas Model Into CFD Analysis for the Simulation of Turbine Exhaust Flows with High Steam Loads

Abstract The Water-Enhanced Turbofan (WET) is a promising future propulsion concept to reduce aero engine emissions. In the WETengine, a heat exchanger uses turbine exhaust heat in order to generate superheated steam out of liquid water. For evaporator design, CFD simulations are necessary since correlation-based predictions have a high uncertainty during preliminary design. A common way of modeling steam loaded flows is the integration of gas models into CFD analysis. However, to the author's knowledge, there is no gas model published that accounts for the exact gas composition of turbine exhaust flows with high steam loads and is commonly used by low- and high-fidelity methods. Therefore, a gas model predicting the thermodynamic behavior of the turbine exhaust flow considering high steam loads is presented and integrated into an existing CFD solver. The approach is able to incorporate the implemented gas model into the CFD simulation by two methods: runtime and offline. The offline method has a computational advantage in iteration time compared to the runtime integration. As demonstration case, a single two dimensional cylinder is considered. A variation of the steam loading of the flow shows a significant effect on local properties and therefore on local and average heat transfer. Increasing the steam loading up to 40 % results in an increase of the average Nusselt number of 17 %.

Performance analysis of a CO2 near-zero emission integrated system for stepwise recovery of LNG cold energy and GT exhaust heat

Combined cooling, heating and power (CCHP) system can further improve energy utilization efficiency while meeting diversified energy demands, and the rational use of the CCHP system is an effective way to alleviate the energy crisis. An innovative cascaded CCHP system based on the transcritical carbon dioxide cycle (TRCC) and organic Rankine cycle (ORC) has been proposed, which is designed to recover the cold energy of liquefied natural gas (LNG) and the exhaust heat from the gas turbine (GT), while achieving near-zero CO2 emissions. The simulation result demonstrates that the system achieves energy utilization efficiency, exergy efficiency and net electrical efficiency of 87.3%, 56.9% and 55.39%, respectively, with a CO2 capture rate of 79.2 kg/h under the design condition. Compared to the mentioned cogeneration systems that recover LNG cold energy and GT waste heat, the proposed system exhibits improvements in energy utilization efficiency, exergy efficiency and net electrical efficiency by 9.84%, 4.37% and 3.4%, respectively. The parameter sensitivity analysis reveals that increasing the pressure ratio of the TCO2 turbine and ORC turbine or reducing the air compressor feed temperature can improve the overall performance of the system. If the focus is solely on energy utilization efficiency and exergy efficiency, appropriately increasing the air compressor pressure ratio or reducing the gas turbine pressure ratio would be beneficial. The proposed system in the study is environmentally friendly and energy-saving, which especially suggests a direction for cold energy cascade utilization in LNG stations integrated with CCHP.

Uji Performa Alat Pengering Tray Dryer Untuk Komoditas Hasil Pertanian Yang Memanfaatkan Kalor Buangan Kondensor Mesin Pengkondisian Udara (Air Conditioning) Domestik

The drying methods currently used by farmers still rely heavily on direct solar power, so that the continuity of drying to reduce water content cannot be controlled properly, which has a direct impact on the low quantity and quality of drying results, as well as poor product hygiene. Utilization of condenser waste heat from cooling machines is one of the development applications for heat pump systems. The advantages of heat pumps for the drying process include their ability to control the temperature and humidity in the drying chamber, so that they can be adjusted for various drying conditions and the drying process is more efficient and environmentally friendly. This research aims to determine the performance of drying machines for agricultural commodities (cocoa beans) using the method of developing a domestic air conditioning machine, by adding a condenser arranged in series with the main condenser to function as a drying chamber. The results of the modification of this tool consist of five main parts, namely the compressor, tray dryer room (additional condenser), main condenser, expansion valve, and evaporator. Testing of this dryer was carried out with two types of experiments, namely experiments without load and experiments with load. The test was carried out at the maximum working time of the condenser by setting the lowest working evaporator, namely 16°C. The lower the working temperature of the evaporator, the higher the working temperature of condenser 1. This is done to get maximum work from this modified dryer. Based on tests for temperature and relative humidity (RH) under load and no-load conditions, the values are not too different. After approximately 2 hours of operation or when the machine was working in steady state, the highest temperature was obtained at 87°C while the highest average RH was obtained at 78% in the drying rack space. The performance of this agricultural commodity drying machine has functioned well, especially for cocoa beans which have been dried to a standard moisture content of 7.5% in accordance with SNI 2322-2008 for an operating time of 130 minutes. The dryer system by utilizing exhaust heat from the condenser in this domestic air conditioning machine can work well without reducing its main function as indicated by the maximum temperature value of 20oC around the evaporator.Â

Numerical analysis of a solid oxide fuel cell system integrated with a hybrid desiccant cooling system

Solid oxide fuel cell systems are advantageous in distributed power generation and are commonly utilized in residential buildings. However, since commercialized small-scale solid oxide fuel cells generally produce hot water using high-temperature exhaust gas, it is difficult to utilize thermal energy in high-temperature areas and during the summer. The exhaust heat from the solid oxide fuel cell system can be effectively utilized by integration with the hybrid desiccant cooling system. In this study, a numerical model of a solid oxide fuel cell system integrated with a hybrid desiccant cooling system has been developed to determine the optimal system configuration and operating strategy. As for the Hot-dry, Hot-humid, and Mixed-humid, which are representative climatic conditions of summer in the United States, were selected. The system model has been simulated at a period of the highest electrical demand in a year with each climate. The solid oxide fuel cell-hybrid desiccant cooling system model has been simulated to compare the system efficiency at 4 case. The simulation results show that the solid oxide fuel cell-hybrid desiccant cooling system without a burner has the highest total efficiency of 77.7 % and the highest total coefficient of performance of 1.528 under electric load following operation. This study can provide the basic insight to establish the parametric analysis and control strategy in integrating the solid oxide fuel cell system and the desiccant cooling system.

A review on ammonia-hydrogen fueled internal combustion engines

In the face of the electrification trend in transportation, the internal combustion engine (ICE) is expected to continue playing a vital role in generating electricity for power systems or directly propelling vehicles in certain sectors. However, ICEs are also under significant pressure to achieve carbon neutrality, with the key lying in carbon-free fuels. Ammonia, compared to hydrogen, offers advantages in terms of hydrogen-carrying capacity, storage and transportation convenience, and safety, making it a promising carbon-free fuel for large-scale use in ICEs. Nonetheless, ammonia's combustion inertness poses challenges for its application, requiring efforts to enhance its combustion. Hydrogen, as a carbon-free and highly reactive fuel, serves as a powerful combustion promoter, maximizing the carbon-free effect of ammonia. Furthermore, on-board ammonia decomposition can produce hydrogen, ensuring a stable hydrogen supply and enabling ammonia-hydrogen synergy combustion while carrying only ammonia. This ammonia-hydrogen synergy combustion, based on on-board hydrogen production, presents a highly promising development direction for ammonia engines. When combined with hybridization, it further enhances the overall energy efficiency of ammonia. The objective of this paper is to review recent advancements in ammonia-hydrogen engines, covering topics such as ignition methods and combustion strategies, fuel supply, pollutants, and after-treatment. Based on this review, a conceptual ammonia-hydrogen engine for hybrid power systems is proposed. This engine ignites the ammonia-hydrogen mixture in the main chamber using hydrogen active jet ignition, achieving spark-assisted compression ignition. Technical measures for efficient engine combustion, synergistic utilization of exhaust heat for hydrogen production, and effective after-treatment of NOx, unburned NH3, and N2O are discussed. At last, some perspectives on the development of ammonia-hydrogen engines are also presented.

Design and Implementation of a Control Strategy for a Dynamic Organic Rankine Cycle‐Based Power System in the Context of Industrial Waste Heat Recovery

Transient thermal waste heat sources, such as solar energy, industrial waste heat, and ship exhaust heat, pose significant challenges in terms of their reuse in other processes. Therefore, ensuring the safe and efficient design and operation of the organic Rankine cycle (ORC) system for these heat sources is imperative. Comprehending the ORC system's dynamic characteristics is necessary to formulate suitable control strategies. This article undertakes a comprehensive review of previous studies on dynamic modeling and control of the ORC system and discusses the prevalent dynamic modeling methodologies, the challenges frequently encountered in dynamic simulations, and a range of control strategies. This article comprehensively analyzes the overall control strategies used by ORC systems. Additionally, the energy conversion systems utilized in ORC are depicted in detail. Furthermore, using model predictive control in a simulation study allows for investigating various components’ disturbance and dynamic characteristics within the ORC system. These components include the expander, pump, condenser, and evaporator using setpoint tracking. Ultimately, this analysis aims to optimize the performance of the ORC cycle. The findings indicate that the utilization of superheating in the working fluid is the most effective method for achieving maximum power generation in an ORC system.

Rational design process for gas turbine exhaust to supercritical CO2 waste heat recovery heat exchanger using topology optimization

Advances in additive manufacturing (AM) technologies and topology optimization methodologies are enabling sophisticated novel designs for heat exchanger performance. These tools have been demonstrated for development of high-performance heat sinks considering local or component-level performance factors (e.g., heat transfer per volume). To leverage such capabilities in larger-scale energy systems, structured design methodologies are needed that consider system-level factors, such as production cost, cycle-level efficiency, and operational constraints. This study seeks to develop and assess a rational approach for designing thermo-economically optimal heat exchangers for such applications. The methodology is illustrated through development of the Primary Heat Exchanger (PHX) for a supercritical carbon dioxide (sCO2) power cycle recovering exhaust heat from a 6 MW-scale natural gas turbine. The proposed approach begins with a detailed thermodynamic cycle model, which is then extended to account for techno-economics. Next, an optimal PHX heat transfer capacity target is identified, and a high-level geometry is selected based on operating characteristics. This geometry is then divided into repeating 2D prismatic unit cells, for which topology optimization is applied to identify high-performance heat transfer geometries. A key aspect of this process is that the unit cell geometries are optimized using the total PHX mass as the objective function, which represents a surrogate for production cost. This leads to distinct designs compared with approaches that optimize local heat transfer and flow resistance factors. A second topology-optimized design is developed using a representative local thermal-fluid performance objective function and is found to require 1.6× the mass of the design generated with the system-level techno-economic objective for the same unit cell size. Conventional-type PHX designs with simple longitudinally finned tubes are developed for comparison, and are found to require total masses 1.5× or greater than the design obtained with the proposed process. Integrating this approach with detailed additive manufacturing costing models and experimentally validated fabrication constraints can yield a streamlined workflow for HX design for future energy systems.

Exergy-economic analysis of a hybrid combined supercritical Brayton cycle-organic Rankine cycle using biogas and solar PTC system as energy sources

Environmental negative impacts of the fossil fuels and intermittent feature of the renewable energies have made their hybrid configurations as a potential solution to overcome their both weaknesses. This research focuses on exergetic, and economic evaluation of a novel hybrid combined supercritical Brayton Cycle-Organic Rankine Cycle in which Solar PTC system and Biogas are considered as the energy Sources. The exhaust heat from the Bryton cycle runs the Organic Rankine cycle while either solar energy (during the daylight hours) or biogas energy (overnight hours) supply additional heat into the Brayton cycle. Sensitivity analyses were carried out in order to ascertain the influence that the system's input characteristics. The total exergy destruction of the system as well as its second law efficiency are computed. The process was not complete until exergoeconomics was used, and it was during this stage that the initial investment rate, the exorgoeconomic component, and the investment return rate are figured out. The findings of these analyses are compiled into a result report. It was concluded that combining the PTC system with the source of the biogas could be an effective way to achieve the desired level of heat delivery to the system.

Energy Recovery Based on Exhaust Gas Recirculation and Heat Regeneration Processes Applied in a Firewood Boiler

Energy Recovery Based on Exhaust Gas Recirculation and Heat Regeneration Processes Applied in a Firewood Boiler

Review on the thermal neutrality of application-oriented liquid organic hydrogen carrier for hydrogen energy storage and delivery

The depletion and overuse of fossil fuels present formidable challenge to energy supply system and environment. The human society is in great need of clean, renewable and sustainable energy which can guarantee the long-term utilization without leading to escalation of greenhouse effect. Hydrogen, as an extraordinary secondary energy, is capable of realizing the target of environmental protection and transferring the intermittent primary energy to the application terminal, while its nature of low volumetric energy density and volatility need suitable storage method and proper carrier. In this context, liquid organic hydrogen carrier (LOHC), among a series of storage methods such as compressed and liquefied hydrogen, provokes a considerable amount of research interest, since it is proven to be a suitable carrier for hydrogen with safety and stability. However, the dehydrogenation of hydrogen-rich LOHC materials is an endothermic process and needs large energy consumption, which hampers the scale up of the LOHC system. The heat issue is thus essential to be addressed for fulfilling the potential of LOHC. In this work, several strategies of heat intensification and management for LOHC system, including the microwave irradiation, circulation of exhaust heat and direct LOHC fuel cell, are summarized and analyzed to provide suggestions and directions for future research.

Thermodynamic and techno-economic analysis of a direct thermal oil vaporization solar power system

A unique direct thermal oil vaporization solar power system employing cascade organic-steam Rankine cycle is proposed. The oil is a mixture of biphenyl and diphenyl oxide, and it is used for heat transfer, storage and power cycle fluid in the novel system. Stable electricity output and prolonged storage capacity can be facilitated. In the rated mode, the oil is vaporized at 390 °C in the collectors and drives a top turbine. The exhaust heat is used for preheating and evaporating water of the bottom cycle. Meanwhile, the hot oil in a high-temperature tank (HTT) superheats and reheats the generated steam. When the irradiation is insufficient, the heat released by the oil from the HTT to a low-temperature tank drives the bottom cycle. Fundamentals, thermodynamic performance and techno-economic feasibility are elaborated. The results indicate that, compared with the mainstream dual-tank solar power systems, the proposed system has a higher thermal efficiency with a lower water evaporation temperature (42.90% at 260 °C vs. 38.06% at 310 °C) and a larger temperature drop between the two tanks (121 °C vs. 100 °C). The equivalent payback time with respect to the top oil cycle is less than 3 years.

Waste heat recovery assessment of triple heat-exchanger usage for ship main engine pre-heating and fresh water generation systems

In this study, the applicability, fuel saving and CO2 emission reducing potential of the triple heat-exchanger fed by the diesel generator exhaust gas with and without water steam have been studied for ship’s one and two main engines pre-heating and freshwater generation (FWG) cycles under port conditions with conducting energy and exergy analysis. The performance criteria (PC) and exergy efficiency (ε) values of the main engine pre-heating and freshwater generator systems of the Ro-Ro ship selected for the case study were determined by written Matlab 2021a codes merging CoolProp 6.4.2 database with Python. It was determined that even at the lowest operating load of the diesel generator (25%), the exhaust heat energy would be sufficient to preheat the main engine and generating fresh water with also saving fuel consumption. As a result, during the 12-h port period, each 1 kW heat energy reduction on steam will provide 0.0853 kg/h fuel saving in the boiler. Thus, 273 kg CO2 emission will be reduced for each kW of heat energy to be obtained. Considering the comparatively increased PC and ε values of whole system cycle containing common triple heat-exchanger for two main engines, it can be used conveniently and reliably on ships.

A technically feasible strategy using liquid-state thermocells to efficiently recover the waste heat released from proton exchange membrane fuel cells

Proton exchange membrane fuel cells (PEMFCs) generate a large amount of exhaust heat during operation, leading to environmental pollution and the greenhouse effect. To recover the low-grade exhaust heat produced by PEMFCs, a technically feasible approach is proposed by integrating liquid-state thermocells (LTCs) with PEMFCs for the cogeneration of electric power and efficient waste heat recovery. Considering the three overpotential losses in the PEMFC and the irreversible heat losses in the LTC, a comprehensive mathematical model of a PEMFC-LTC hybrid system is developed to explore the energetic performance characteristics and optimal device design. The results show that the hybrid system’s maximum power density and corresponding conversion efficiency are 0.3007 W cm−2 and 24.59%, which is increased by 6.22% and 19.41% compared to a single PEMFC, respectively. Furthermore, raising the PEMFC temperature, optimizing the length of the individual LTC cell, reducing the heat sink temperature, and lowering the thermal convection coefficient can significantly improve the optimal output performance of the hybrid system. Finally, the optimal performance comparisons between the PEMFC-based cogeneration systems reveal that LTCs can more efficiently recycle the waste heat released from the PEMFC than other previously reported devices. This work offers crucial theoretical guidance for the optimal design and parametric analysis of PEMFC-LTC hybrid systems, thus paving the way for developing high-performance energy cascade utilization systems based on PEMFCs.

Thermodynamic and feasibility analysis of using diesel generator exhaust gases for ship main engine preheating at port periods

In this study, the feasibility and potential impact on fuel consumption of the proposed preheating system driven by diesel generator exhaust gas instead of steam to satisfy main engine pre-heating demands especially under port operation conditions have been analyzed according to the 1st and 2nd laws of thermodynamics. The proposed novel term named performance criteria (PC) and exergy efficiency (ε) values of the main engine preheating and cooling water systems of the Ro-Ro ship selected for the case study under the existing voyage and port operating conditions have been determined by written Matlab-2021a codes merging CoolProp-6.4.2 database with Python. It was determined that even at the lowest operating load of the diesel generator (25%), the exhaust heat energy would be sufficient to preheat the main engine with also reducing the fuel consumption. As a result, during the 12-hour port period, 22% of the boiler fuel consumption and 8% of the ship's fuel consumption can be saved. Accordingly, if a shipping company uses Mine Gas Oil as fuel, it will be able to achieve fuel savings of approximately US$ 32.000 on annual basis. Considering the fuel saving values, it has been determined that 1.016 tons of CO2 emissions for per port operation and 106 tons of annual CO2 emissions can be reduced. It was determined that, the PC and Ɛ values of the system decrease as the ambient temperature increases. In this context, there is a 7% decrease in the PC and a 5% decrease in the Ɛ for existing system and 8% decrease in the PC and a 2.5% decrease in the Ɛ for proposed system. It was also determined that the proposed new system is both physically and economically feasible and that the investment cost, which was determined to be in the range of US$ 30.000-US$ 35.000, can pay for itself after 1 year.

Numerical analysis of the effects of interconnector design and operating parameters on solid oxide fuel cell performance

Fuel cells can provide higher electrical conversion efficiency than traditional coal-fired power plants and electric generators based on internal combustion engines. In addition, high-efficiency solid oxide fuel cells (SOFC) have two specific advantages compared with other fuel cells as a result of their high-temperature operation. First, SOFCs are compatible with various fuels, ranging from hydrogen to CO and hydrocarbons. Second, SOFCs generate significant amounts of exhaust heat that can be used in combined heat and power systems. Furthermore, SOFCs have quiet and vibration-free operation, eliminating the noise typically associated with power generation systems. These fuel cells also produce no or very low levels of SO2 and NO emissions. In this study, we numerically investigated the performance of a planar SOFC with different interconnector designs at various operating temperatures. Multiple parameters were considered, such as interconnection geometries, anode and cathode materials, operating temperatures, and flow rates. As a result, the horizontal sinusoidal flow channel geometry, operating temperature of 600 °C, hydrogen gas flow rate of 86.5 SCCM/min, and oxygen gas flow rate of 28.75 SCCM/min, NiO anode material, and LSCF cathode material provided the greatest performance in terms of energy and current density.