Hydrogen Internal Combustion Engine Research Articles

Comparative Analysis Of Cycle-To-Cycle Variabilities And Combustion Development In An Optical Spark-Ignition Engine Fueled By Pure Hydrogen And Propane: Insights From Chemiluminescence and PI

Hydrogen, derived from renewable sources and devoid of carbon emissions, is a pivotal energy carrier for the future. Representing a viable substitute for fossil fuels in internal combustion engines (ICEs), contemporary studies advocate using very-lean and ultra-lean hydrogen-air mixtures, with a fuel-air equivalence ratio below 0.5, as a potent strategy to reduce NOx emissions in hydrogen-fueled ICEs. An experimental setup with an optical spark-ignition engine was devised to investigate the primary factors influencing cycle-to-cycle variations in H2ICEs by optimizing mixture homogeneity and focusing the study on flame interaction with in-cylinder aerodynamics. Simultaneous in-cylinder pressure, chemiluminescence, and PIV analyses were performed to characterize and compare the behaviors of ultra-lean hydrogen-air and propane-air flames, assessing flame development and cyclic variation features. Results indicate that the flame development of hydrogen and propane is significantly different. Propane exhibited increased in-cylinder pressure trace variability at lean and rich flammability limits with a high flame development difference between fast and slow cycles. In contrast, hydrogen-air mixtures under various equivalence ratios (from very-lean to ultra-lean) presented much more stable in-cylinder pressures. Furthermore, fast propane flames were mainly advected to the cylinder's symmetrical axes, while fast hydrogen flames started further away from the spark plug. Horizontal and vertical PIV measurements showed a single structure flow field over the studied conditions with mainly intensity variations over the measured cycles. Fast flames were associated with more intense tumble motion. The differences between fast and slow flames for hydrogen are attributed to the early flame development. However, after initial differences in flame development over several crank angles, there are similarities in all cycles, suggesting that the low variability in in-cylinder pressures is mostly due to the robustness of hydrogen flame ignition and its independence from in-cylinder flow small variations at the early development phase.

Well-to-wheel carbon footprint and cost analysis of gasoline, diesel, hydrogen ICE, hybrid and fully electric city buses

Carbon emissions in mobility, as one of the primary causes of global warming, are regulated by various organizations with different legislations. Different energy sources and power-train solutions are used to comply with these constraints. Hydrogen-fueled, fully electric, and hybrid vehicles are at the forefront of these technologies. Within the scope of this study, gasoline-, diesel-, and hydrogen-fueled internal combustion engines, and fully electric and serial hybrid 18-m city bus vehicles were modeled. Comprehensive analyses of emissions and costs, considering both the entire energy production and consumption cycles for various vehicle types were conducted. Models that are primarily based on fuel consumption data show that while fully electric vehicles currently have the lowest emissions, hydrogen-fueled vehicles can play a more prominent role soon with the increasing production of green hydrogen. For the first step of hydrogen implementation in the industry, H2ICE is a promising for both reduced carbon emissions in mobility and cost-effectiveness. If the forecasted hydrogen production and distribution scenario is adopted by industrial and energy organizations, it is evident that by the year 2030, more environmentally friendly operation can be achieved particularly in the context of public transportation. Embracing this approach is likely to lead to positive environmental sustainability impacts in future transportation systems.

Development of a method to investigate the influence of engine oil and its additives on combustion anomalies in hydrogen engines

To counteract the anticipated consequences of climate change, significant efforts are required across all industries. The use of hydrogen in internal combustion engines can make a valuable contribution as a carbon-neutral bridging technology. One challenge in developing a suitable combustion process is the high ignition propensity of hydrogen, impacting combustion stability due to combustion anomalies. Avoiding such combustion phenomena is of utmost relevance to ensure a long-term stable engine operation. Oil entry into the combustion chamber can impact the occurrence of combustion anomalies. Therefore, a specific method for controlled oil entry into the combustion chamber has been developed, and this method is detailed in the following article.

Techno-economic assessment of hydrogen as a fuel for internal combustion engines and proton exchange membrane fuel cells on long haul applications

Powertrain energy conversion and management are critical factors in providing affordable and robust solutions for transport decarbonization. Various powertrain technologies are being proposed to reduce the impacts of transportation-related carbon dioxide emissions, such as battery electric, fuel cell, and conventional vehicles running with lower carbon fuels. Specifically for the commercial sector, hydrogen internal combustion engines and fuel cells are being extensively discussed. In this sense, this investigation evaluates the benefits and areas of enhancement for hydrogen internal combustion engines and fuel cells from a techno-economic perspective. Power plant models were developed and validated in GT-Power, and detailed investigations on the energy loss pathways were performed. In addition, the powertrains are included in full longitudinal vehicle models and submitted to different driving cycles, representing homologation and real-world driving conditions, with the intent to understand the effect of the cycles from a global energy management perspective. Finally, the fuel consumption results are used as inputs for a total cost of ownership calculation to determine the economic viability of each powertrain. Overall, fuel cells offered efficient operation across the conditions assessed, with engine-powered powertrains showing reduced efficiencies ranging from 23 % to 63 % depending on the cycle and payload. The limited peak efficiency for the spark-ignited low-pressure hydrogen direct injection engine was a dominant factor for the reduced performance of this platform. Strategies for efficiency improvement are identified that could lead to improved internal combustion engine operation. Despite the limited efficiency benefits of hydrogen internal combustion engines, total cost of ownership calculations show hydrogen internal combustion engines being the most cost-effective solution in the near to medium-term scenario.

Revealing the roles of Zr on enhanced H2-SCR performances on Pt/TiO2 catalyst

The development of Hydrogen Internal Combustion Engine (H2-ICEs) to replace conventional fuel engines is expected to be an effective way to reduce CO2 emissions, but some NOx emitted from the H2-ICEs still should be eliminated by the selective catalytic reduction of NOx with H2 (H2-SCR). Large amount of platinum oxide existed on Pt/TiO2 leads to its low H2-SCR activity. In contrast, the Zr-modified Pt/TiO2 catalysts exhibit a higher NOx conversion and N2 selectivity in a wider temperature window (100–180 °C) than those of Pt/TiO2. The appropriately weakened strong interaction between Pt and TiO2 by Zr induces more Pt0 species, which are active sites for the activation of NOx and H2 in H2-SCR reaction. More oxygen vacancies caused by the formation of Zr-Ov-Ti3+ bands involve in the activation of NOx and the adsorption of nitrates (NOx−) species. Furthermore, in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTs) demonstrates that Pt/ZrxTi1-x catalysts possess more adsorbed NOx− species and a faster reduction rate for them. Monodentate and bridged nitrates are considered to be more reactive with H2 than bidentate nitrates at relatively low temperatures. This work provides directions for the development of high-performance H2-SCR catalysts and the modulation of the conversion temperature.

Applications of Oxyhydrogen, Direct Water Injection, and Early-Intake Valve Closure Technologies on a Petrol Spark Ignition Engine—A Path towards Zero-Emission Hydrogen Internal Combustion Engines

This study investigates the performance of a 4-MIX engine utilizing hydrogen combustion in pure oxygen, water injection, and the application of the early-intake valve closure (EIVC) Miller cycle. Transitioning from a standard petrol–oil mix to hydrogen fuel with pure oxygen combustion aims to reduce emissions. Performance comparisons between baseline and oxyhydrogen engines showed proportional growth in the energy input rate with increasing rotational speed. The oxyhydrogen engine exhibited smoother reductions in brake torque and thermal efficiency as rotational speed increased compared to the baseline, attributed to hydrogen’s higher heating value. Water injection targeted cylinder and exhaust temperature reduction while maintaining a consistent injected mass. The results indicated a threshold of around 2.5 kg/h for the optimal water injection rate, beyond which positive effects on engine performance emerged. Investigation into the EIVC Miller cycle revealed improvements in brake torque, thermal efficiency, and brake specific fuel consumption as early-intake valve closure increased. Overall, the EIVC model exhibited superior energy efficiency, torque output, and thermal efficiency compared to alternative models, effectively addressing emissions and cylinder temperature concerns.

Optimal 4E evaluation of an innovative solar-wind cogeneration system for sustainable power and fresh water production based on integration of microbial desalination cell, humidification- dehumidification, and reverse osmosis desalination

Reliable freshwater production is vital for tackling two of the most critical challenges the world is facing today: climate change and sustainable development. Present work presents an innovative cogeneration system based on solar and wind energies for sustainable production of freshwater, power, and wastewater treatment. For freshwater production and wastewater treatment in this system, the integration of a microbial desalination cell with a humidification-dehumidification and reverse osmosis desalinations has been used. The mentioned systems provide their heat demand from solar energy, and when solar radiation is unable to provide this heat, a hydrogen internal combustion engine drive produces the required heat for the freshwater plant. Excess heat from the hydrogen internal combustion engine is fed into the organic Rankine cycle for more power generation in the whole system to reduce system waste heat and increase efficiency. PEM electrolyzer has been used to supply the hydrogen needed by the internal combustion engine, and this system uses wind turbines to supply the power demand. To evaluate the performance of the whole system, energy, exergy, exergeoeconomic, and exergoenvironmental (4E) analyses have been carried out. Finally, to improve the performance parameters of the system, multi-objective optimization using the Salp swarm algorithm has been used. Investigation of the results show that the proposed system can produce 720 kW of electricity and 5.36 m3/h of freshwater. The energy efficiency of the system is 22.09 %, and its overall cost rate and overall environmental impact rate are 540.33 $/hr and 17.37 Pt/h, respectively. Among the qualitative results obtained in this research, it is possible to mention the high exergy destruction, cost destruction, and environmental impact destruction of the internal combustion engine compared to other equipment used in the proposed system, and this point shows the need to improve this equipment, similar to previous researches. The five-objective optimization results of the proposed system showed that the performance parameters of the system, such as polygeneration energy efficiency, total cost rate, and total environmental impact rate, can be improved by 6.2 %, 1.44 %, and 0.52 %, respectively. The payback period of the proposed system in the optimal state is 6.95 years.

Study on backfire characteristics of port fuel injection single-cylinder hydrogen internal combustion engine

Hydrogen energy is one of the most promising sources of carbon neutrality from well to wheel. Among various applications of hydrogen energy, hydrogen internal combustion engines serve as the critical technical pathway. Nevertheless, several challenges persist, primarily related to abnormal combustion resulting from excessive flame propagation velocity. Of these challenges, backfire emerges as the most recurrent and pressing issue to be resolved in the port fuel-injected hydrogen internal combustion engine (PFI-H2ICE). In order to delve into the characteristics and mechanisms of backfire, this study concentrates on a critical internal parameter, namely the start of injection (SOI), and comprehensively assesses the backfire occurrences under varying lambda and engine speed conditions. Experimental findings reveal that SOI encompasses one of the pivotal factors influencing backfire. Backfire predominantly arises within two ranges of SOI conditions: the region before −430 degCA ATDC (Zone I) and the stretch between −360 degCA ATDC and − 280 degCA ATDC (Zone II). In the process of employing EGR to depress the effects of backfire on subsequent tests, it was incidentally found that the Universal Exhaust Gas Oxygen Sensor (UEGO) installed on the intake manifold for executing EGR rate calculations acted as a hotspot (with temperatures exceeding 100 °C). This not only intensified the backfire strength and the scope in Zone I but also caused the most severe backfire events to occur after −270 degCA ATDC (in Zone III). Despite this, the EGR strategy still demonstrated a significant backfire suppression effect, only exhibiting almost no influence on backfire caused by hotspots within the intake manifold. With an escalation in engine speed, the intensity of backfire diminishes, and the range of backfire occurrence decreases accordingly. By exercising control over SOI within the operating range from -430degCA to -360degCA ATDC (Zone A), the risk of backfire can be dramatically reduced, thereby achieving nearly backfire-free operation. Detailed analysis of cylinder pressure indicates that backfire may also give rise to other abnormal combustions, such as misfire, pre-ignition, and knock, in subsequent cycles. Moreover, this effect amplifies in tandem with an increase in mixture concentration. A certain degree of mutual promotion among diverse abnormal combustions is also observed. This study furnishes the most direct and practical foundation for internal and external strategies in the realm of backfire control.

Potential of Hydrogen Internal Combustion Engine for the Decarbonised Passenger Vehicle

CO2 regulations are becoming very stringent due to the goal of reducing greenhouse gases and achieving carbon neutrality. It has already become a common situation that electric vehicles are emerging as eco-friendly power systems rather than vehicles equipped with conventional internal combustion engines and their share in the market is increasing. However, even with an internal combustion engine, CO2 can be drastically reduced if a carbon-free fuel such as hydrogen is used. Raw nitrogen oxides (NOx) emissions can be overcome to a certain level through ultra-lean burn operation, but in order to balance the amount of hydrogen and air in the limited space of the combustion chamber, a drop in the engine’s maximum output should be accepted. Hyundai Motor Company (HMC) also previously developed an engine using hydrogen fuel (), but was unable to progress to mass production. Since then, hybrid technology has become popular, and with the development of hydrogen injection devices, an era has arrived where mass production becomes a possibility. For this reason, studies on internal combustion engines using hydrogen fuel based on existing spark ignition or compression ignition engines are rapidly increasing. In this study, a hydrogen fuel engine was designed and manufactured based on the mass produced gasoline spark ignition engine. CO2 level was confirmed from initial performance evaluation, and it was found that raw NOx levels and maximum power were in a trade-off relationship with each other under the same air-charging system application. In addition, the method to improve maximum engine torque was verified while maintaining the raw NOx level, and the maximum engine power improvement level was confirmed when raw NOx emissions were allowed to increase. Thereby the potential of the carbon-neutral internal combustion engine has been demonstrated.

High-Performance Hydrogen-Fueled Internal Combustion Engines: Feasibility Study and Optimization via 1D-CFD Modeling

Hydrogen-powered mobility is believed to be crucial in the future, as hydrogen constitutes a promising solution to make up for the non-programmable character of the renewable energy sources. In this context, the hydrogen-fueled internal combustion engine represents one of the suitable technical solutions for the future of sustainable mobility. As a matter of fact, hydrogen engines suffer from limitations in volumetric efficiency due to the very low density of the fuel. Consequently, hydrogen-fueled ICEs can reach sufficient torque and power density only if suitable supercharging solutions are developed. Moreover, gaseous-engine performance can be improved to a great extent if direct injection is applied. In this perspective, a remarkable know-how has been developed in the last two decades on NG engines, which can be successfully exploited in this context. The objective of this paper is twofold. In the first part, a feasibility study has been carried out with reference to a typical 2000cc SI engine by means of 1D simulations. This study was aimed at characterizing the performance on the full load curve with respect to a baseline PFI engine fueled by NG. In this phase, the turbocharging/supercharging device has not been included in the model in order to quantify the attainable benefits in the absence of any limitation coming from the turbocharger. In the second part of this paper, the conversion of a prototype 1400cc direct injection NG engine, running with stoichiometric mixture, to run on a lean hydrogen combustion mode has been investigated via 1D simulations. The matching between engine and turbocharger has been included in the model, and the effects of two different turbomatching choices have been presented and discussed.

Optimizing Hydrogen and Ammonia Injection Timing for Enhanced Mixture Formation in Internal Combustion Engines

Hydrogen and ammonia are two carbon-free alternative fuels for engines. They represent some of the most viable pathways toward achieving our objectives of energy conservation and reducing emissions. To research the quality of the hydrogen-ammonia-air mixture formation under different hydrogen/ammonia injection timing, a three-dimensional simulation model for a PFI(Port Fuel Injection) hydrogen internal combustion engine with the inlet, outlet, valves and cylinder was established using Converge software. Research focused on the space distribution characteristics and variation law of velocity field, concentration field and turbulent kinetic energy under different injection timings in order to reveal the influence of these parameters on hydrogen-ammonia-air mixture formation process. The results showed that hydrogen injection should be neither too early nor too late. Backfiring can be initiated too early or too late. Therefore, the optimum starting point for hydrogen/ammonia injection should be 338°CA.

Comparative performance analysis of different hydrogen power composite cycles with waste heat recovery

ABSTRACT Hydrogen energy has been under close scrutiny by countries around the world. At present, the main technologies for utilizing hydrogen energy in transport power systems are hydrogen internal combustion engine (HICE) and proton exchange membrane fuel cell (PEMFC). Since both of them generate a large amount of waste heat, and waste heat recovery technology is one of the most promising means of utilizing waste heat to improve efficiency, this paper makes a comprehensive comparison of the two technologies in composite waste heat recovery (WHR) system in terms of modeled maximum efficiency, full operating condition efficiency and future predicted maximum efficiency. Based on the thermal efficiency analysis, the advantages, disadvantages, and development prospects of the two technologies in composite the WHR system are reevaluated. The results demonstrate that the efficiency of the HICE and PEMFC can be improved by 6.83% and 2.81%, with the use of WHR system, respectively. Under the full range of operating conditions, the HICE-WHR composite system has obvious efficiency advantage in middle-high load working condition, but PEMFC-WHR composite system has obvious efficiency advantage in low load working condition. Both of them will be very competitive and potential technology routes of hydrogen energy utilization for land transportation.

Hydrogen as Fuel for ICEs: State of Art and Technological Challenges

The climate change, as the main consequence of the polluting emissions due to anthropic activities, is nowadays a well-known threat to human health as well as for the environment safety. Several plans and strategies have been announced by the governments to detach from fossil fuel-based energy and gradually reduce the carbon footprint of their economies. In this scenario, the road transport sector is turning out to be the main “technological gym” to test and improve new powertrain solutions to achieve as soon as possible the goal of the net-zero carbon emissions, at least in the tank-to-wheel (TTW) context. In view of this, the hydrogen as fuel is gaining ever more attention from the scientific community, both as the middle-term solution to achieve the abovementioned goal and as a prominent future energy carrier. In this review, the performance and main characteristics of the hydrogen-internal combustion engines (H2-ICEs) are discussed based on the most recent studies available in literature. A comprehensive overview of various topics is offered, from the production stage to the combustion anomalies, mixture formation strategies, and the challenge of reducing the nitrogen oxides (NOx) emissions under high load conditions.

Experimental Investigations of the Hydrogen Injectors on the Combustion Characteristics and Performance of a Hydrogen Internal Combustion Engine

Hydrogen is regarded as an ideal zero-carbon fuel for an internal combustion engine. However, the low mass flow rate of the hydrogen injector and the low volume heat value of the hydrogen strongly restrict the enhancement of the hydrogen engine performance. This experimental study compared the effects of single-injectors and double-injectors on the engine performance, combustion pressure, heat release rate, and the coefficient of variation (CoVIMEP) based on a single-cylinder 0.5 L port fuel injection hydrogen engine. The results indicated that the number of hydrogen injectors significantly influences the engine performance. The maximum brake power is improved from 4.3 kW to 6.12 kW when adding the injector. The test demonstrates that the utilization of the double-injector leads to a reduction in hydrogen obstruction in the intake manifold, consequently minimizing the pumping losses. The pump mean effective pressure decreased from −0.049 MPa in the single-injector condition to −0.029 MPa in the double-injector condition with the medium loads. Furthermore, the double-injector exhibits excellent performance in reducing the coefficient of variation. The maximum CoVIMEP decreased from 2.18% in the single-injector configuration to 1.92% in the double-injector configuration. This result provides new insights for optimizing hydrogen engine injector design and optimizing the combustion process.

Ammonia combustion using hydrogen jet ignition (AHJI) in internal combustion engines

The application of ammonia and hydrogen in internal combustion engines (ICE) is a promising zero-carbon technology. This paper investigates ammonia combustion in ICE using hydrogen multiple-injection jet-ignition (MIJI). The experiment was conducted on a single-cylinder heavy-duty engine with a compression ratio of 17 and a cylinder bore of 123 mm. In the passive jet ignition mode, the minimum hydrogen energy ratio for stable operation of the ammonia-hydrogen engine was 15 %. Using H2 active jet ignition could improve the combustion stability significantly. It was found that engine performance was gradually improved by H2 injection strategy in order of single-injection, double-injection to triple-injection. The triple-injection strategy could achieve a more ideal distribution of ammonia-hydrogen mixture: the first injection forms a homogeneous mixture to increase fuel reactivity; the second injection creates a stratified hydrogen mixture, facilitating rapid flame propagation; the third injection forms a relatively rich mixture in the jet chamber conducive to spark ignition. Through the optimization of the hydrogen injection strategy and spark timing, stable combustion (COV = 1 %) and high thermal efficiency (ITE = 42.5 %) in ammonia-hydrogen engines were achieved, with a minimum hydrogen energy ratio less than 3 %.

Numerical investigation on gaseous fuel injection strategies on combustion characteristics and NO emission performance in a pure hydrogen engine

With the proposal of “dual-carbon” goals and increasingly stringent emission regulations, hydrogen as a zero-carbon alternative fuel has great potential in engine applications. In the appliance of pure hydrogen engines, direct injection plus lean burn technology can effectively improve engine performance and reduce emissions. Therefore, this work establishes a three-dimensional (3D) simulation model of the pure hydrogen spark-ignition internal combustion engine (ICE) coupled with chemical reaction kinetics. Then, the applicability of different commonly used hydrogen simplified mechanisms to characterize the combustion process based on experimental data is evaluated, and the feasibility of the transient calculation model is verified. Then, the engine combustion and emission performance are compared by adopting hydrogen port injection (HPI) and hydrogen direct injection (HDI) strategies. Meanwhile, the effects of hydrogen injection timing (HIT) on flow, combustion and nitric oxide (NO) emission processes under direct injection plus lean burn mode are analyzed. The results show that: 1. For mixture distribution at ignition timing (IT), the hydrogen should be distributed near the spark plug and avoid its concentration being too rich since the richer mixture will lead to intense combustion and rapid heat release. 2. When using HDI mode, the engine combustion performance and power performance are better than that of the HPI mode. Delaying HIT, the power performance improves under HDI modes, while both the indicated thermal efficiency (ITE) and indicated mean effective pressure (IMEP) reached the maximum at Case6-HDI-100 with the values are 40.52 % and 0.498 MPa, respectively. 3. Considering the engine combustion, power and emission performance, Case6-HDI-100 (HIT at 100 °CA BTDC) is the preferred scheme. Its ITE and IMEP are 8.49 % and 37.33 % higher than that of Case1-HPI (HPI mode scheme) and 6.50 % and 14.95 % higher than that of Case4-HDI-220 (the lowest scheme under HDI mode), respectively, while nitrogen oxide (NOx) emissions meet the European Stage V non-road emission standards. This study provides some reference values for the combustion design of pure hydrogen ICEs.

Experimental study on the factors influencing performance and emissions of hydrogen internal combustion engines

Hydrogen internal combustion engines (H2-ICEs) have advantages such as clean combustion and zero carbon emissions, and have become one of the important technical routes for decarbonization in the internal combustion engine industry. In this paper, several key factors affecting the performance and emissions of hydrogen internal combustion engines, such as ignition timing, excess air coefficient, and hydrogen injection timing, were systematically studied on a spark ignition multi-point injection (MPI) hydrogen internal combustion engine bench. The experimental results indicate that the ignition timing controls the combustion phase of hydrogen. Moderate early ignition can improve the brake thermal efficiency (BTE) while having little impact on the NOX emissions. Excess air coefficient(λ) can significantly affect the performance and emissions of H2-ICE. Along with the increase of the λ, the NOX emissions first increases and then continues to decline. When the λ reaching 2.1 or above, near zero emissions of NOX can be achieved. The advance of hydrogen injection timing will slightly increase the peak of cylinder pressure and instantaneous heat release rate. However, overall, the impact of hydrogen injection timing on BTE and NOX emissions is not significant on MPI H2-ICE.

Race towards net zero emissions (NZE) by 2050: Reviewing a decade of research on hydrogen-fuelled internal combustion engines (ICE)

Hydrogen fuel offers promising decarbonization pathways for hard-to-electrify transport sectors such as long-haul trucking, international maritime, and aviation. The internal combustion engine (ICE) is and will continue to be an...

Race towards net zero emissions (NZE) by 2050: Reviewing a decade of research on hydrogen-fuelled internal combustion engines (ICE)

Hydrogen fuel offers promising decarbonization pathways for hard-to-electrify transport sectors such as long-haul trucking, international maritime, and aviation. The internal combustion engine (ICE) is and will continue to be an...

Development of thermoelectric exhaust energy recovery system of a hydrogen internal combustion engine in a city bus using a Three-Dimensional multiphysics model

In this study, individual thermoelectric generator (TEG) module was developed and validated through comprehensive analyses and experiments. A model of the TEG module was constructed and subsequently verified through a coherent alignment with experimental results, ensuring its viability and accuracy within the application of interest. A thermoelectric exhaust energy recovery (TEER) system designed with a robust rectangular structure was also developed for an urban mass transit bus, which operates using a hydrogen internal combustion engine. By accommodating 40 TEG modules, each complemented with cooling fins, and placing cooling channels at the top and bottom of the exhaust channel, it was demonstrated that a proportionality between the power output and load resistance of the TEER system through a dimensionless analysis. The system’s three-dimensional multiphysics model constructed concurrently with the actual system facilitated both optimization and validation, predicting an energy recovery of 1.0–1.1% from the hydrogen engine exhaust and an optimal load resistance of 3.2 Ω under various operating conditions.