Artículos de revistas: "Hydrogen injection"

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Lafortune, Stéphane, Philippe Gombert, Zbigniew Pokryszka, Elodie Lacroix, Philippe de Donato y Nevila Jozja. "Monitoring Scheme for the Detection of Hydrogen Leakage from a Deep Underground Storage. Part 1: On-Site Validation of an Experimental Protocol via the Combined Injection of Helium and Tracers into an Aquifer". Applied Sciences 10, n.º 17 (1 de septiembre de 2020): 6058. http://dx.doi.org/10.3390/app10176058.

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Massive underground storage of hydrogen could be a way that excess energy is produced in the future, provided that the risks of leakage of this highly flammable gas are managed. The ROSTOCK-H research project plans to simulate a sudden hydrogen leak into an aquifer and to design suitable monitoring, by injecting dissolved hydrogen in the saturated zone of an experimental site. Prior to this, an injection test of tracers and helium-saturated water was carried out to validate the future protocol related to hydrogen. Helium exhibits a comparable physical behavior but is a non-flammable gas which is preferable for a protocol optimization test. The main questions covered the gas saturation conditions of the water, the injection protocol of 5 m3 of gas saturated water, and the monitoring protocol. Due to the low solubility of both helium and hydrogen, it appears that plume dilution will be more important further than 20 m downstream of the injection well and that monitoring must be done close to the well. In the piezometer located 5 m downstream the injection well, the plume peak is intended to arrive about 1 h after injection with a concentration around 1.5 mg·L−1. Taking these results into account should make it possible to complete the next injection of hydrogen.

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2

Shi, Wei Bo y Xiu Min Yu. "Efficiency and Emissions of Spark Ignition Engine Using Hydrogen and Gasoline Mixtures". Advanced Materials Research 1070-1072 (diciembre de 2014): 1835–39. http://dx.doi.org/10.4028/www.scientific.net/amr.1070-1072.1835.

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This paper reviews and summarizes recent developments in hydrogen and gasoline mixtures powered engine research. According to the hydrogen and gasoline injection location, engine can be divided into three categories: hydrogen intake port injection, gasoline direct injection; Hydrogen direct injection, gasoline intake port injection; hydrogen and gasoline intake port injection. Different gasoline and hydrogen injection location determines the engines have different advantages. Follow an overview of spark ignition engine using hydrogen and gasoline mixtures, general trade-off when operating engine on hydrogen and gasoline mixtures are analyzed and highlights regarding accomplishments in efficiency improvement and emissions reduction are presented. These include estimates of efficiency potential of hydrogen and gasoline engines, fuel economy and emissions.

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3

Ma, Honglin. "Effect of Hydrogen Injection Flow Rate on the Performance of In-Cylinder Direct Injection Hydrogen Engines". Trends in Renewable Energy 10, n.º 3 (2024): 266–82. http://dx.doi.org/10.17737/tre.2024.10.3.00177.

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When a hydrogen internal combustion engine uses intake manifold injection to supply hydrogen, it must face the contradiction of abnormal combustion (premature combustion, backfire, etc.). The occurrence of abnormal combustion such as backfire can be avoided by using in-cylinder direct injection of hydrogen. In this paper, the In-Cylinder Direct Injection single-cylinder engine is modified, a three-dimensional simulation model is established, and simulation tests using AVL-Fire software on this basis is conducted. Through the analysis of the research results, the optimal hydrogen injection flow rate for the direct injection hydrogen engine to achieve the best power and economy under different working conditions was obtained. The results show that: under the same speed and load, the increase of hydrogen injection flow rate increases the hydrogen injection speed, which promotes the turbulent motion in the cylinder. At the same time, with the increase of hydrogen injection flow rate, the maximum pressure, temperature, indicated power and indicated thermal efficiency in the engine cylinder generally show a trend of first increasing and then decreasing, and there is an optimal hydrogen injection flow rate value.

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4

Pan, Shiyi, Jinhua Wang, Bin Liang, Hao Duan y Zuohua Huang. "Experimental Study on the Effects of Hydrogen Injection Strategy on the Combustion and Emissions of a Hydrogen/Gasoline Dual Fuel SI Engine under Lean Burn Condition". Applied Sciences 12, n.º 20 (19 de octubre de 2022): 10549. http://dx.doi.org/10.3390/app122010549.

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Hydrogen addition can improve the performance and extend the lean burn limit of gasoline engines. Different hydrogen injection strategies lead to different types of hydrogen mixture distribution (HMD), which affects the engine performance. Therefore, the present study experimentally investigated the effects of hydrogen injection strategy on the combustion and emissions of a hydrogen/gasoline dual-fuel port-injection engine under lean-burn conditions. Four different hydrogen injection strategies were explored: hydrogen direct injection (HDI), forming a stratified hydrogen mixture distribution (SHMD); hydrogen intake port injection, forming a premixed hydrogen mixture distribution (PHMD); split hydrogen direct injection (SHDI), forming a partially premixed hydrogen mixture distribution (PPHMD); and no hydrogen addition (NHMD). The results showed that 20% hydrogen addition could extend the lean burn limit from 1.5 to 2.8. With the increase in the excess air ratio, the optimum HMD changed from PPHMD to SHMD. The maximum brake thermal efficiency was obtained with an excess air ratio of 1.5 with PPHMD. The coefficient of variation (COV) with NHMD was higher than that with hydrogen addition, since the hydrogen enhanced the stability of ignition and combustion. The engine presented the lowest emissions with PHMD. There were almost no carbon monoxide (CO) and nitrogen oxides (NOx) emissions when the excess air ratio was, respectively, more than 1.4 and 2.0.

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5

Kim, Y. Y., Jong T. Lee y J. A. Caton. "The Development of a Dual-Injection Hydrogen-Fueled Engine With High Power and High Efficiency". Journal of Engineering for Gas Turbines and Power 128, n.º 1 (22 de noviembre de 2005): 203–12. http://dx.doi.org/10.1115/1.1805551.

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To achieve high power and high efficiency in a hydrogen-fueled engine for all load conditions, the dual-injection hydrogen-fueled engine, which can derive the advantages of both high efficiency from external mixture hydrogen engine and high power from direct cylinder injection was developed. For verifying the feasibility of the above engine, a high-pressure hydrogen injector of ball-valve type and actuated by a solenoid was developed. A systematic experimental study was conducted by using a modified single-cylinder dual-injection hydrogen-fueled engine, which was equipped with both an intake injector and high-pressure in-cylinder injector. The results showed that (i) the developed high pressure hydrogen injector with a solenoid actuator had good gas tightness and fine control performance, (ii) the transient injection region, in which injection methods are changed from external fuel injection to direct-cylinder injection, ranged from 59 to 74% of the load, and (iii) the dual-injection hydrogen-fueled engine had the maximum torque of direct-cylinder fuel injection and the maximum efficiency of external fuel mixture hydrogen engines.

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6

Feuk, Henrik, Francesco Pignatelli, Arman Subash, Ruike Bi, Robert-Zoltán Szász, Xue-Song Bai, Daniel Lörstad y Mattias Richter. "Impact of Methane and Hydrogen-Enriched Methane Pilot Injection on the Surface Temperature of a Scaled-Down Burner Nozzle Measured Using Phosphor Thermometry". International Journal of Turbomachinery, Propulsion and Power 7, n.º 4 (1 de noviembre de 2022): 29. http://dx.doi.org/10.3390/ijtpp7040029.

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The surface temperature of a burner nozzle using three different pilot hardware configurations was measured using lifetime phosphor thermometry with the ZnS:Ag phosphor in a gas turbine model combustor designed to mimic the Siemens DLE (Dry Low Emission) burner. The three pilot hardware configurations included a non-premixed pilot injection setup and two partially premixed pilot injections where one had a relatively higher degree of premixing. For each pilot hardware configuration, the combustor was operated with either methane or hydrogen-enriched methane (H2/CH4: 50/50 in volume %). The local heating from pilot flames was much more significant for hydrogen-enriched methane compared with pure methane due to the pilot flames being in general more closely attached to the pilot nozzles with hydrogen-enriched methane. For the methane fuel, the average surface temperature of the burner nozzle was approximately 40 K higher for the partially premixed pilot injection configuration with a lower degree of mixing as compared to the non-premixed pilot injection configuration. In contrast, with the hydrogen-enriched methane fuel, the differences in surface temperature between the different pilot injection hardware configurations were much smaller due to the close-to-nozzle frame structure.

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7

Bidzhieva, Salimat Kh, Nauruzbek K. Nurseitov, Tilektes B. Kalmukhanova y Maksat S. Utepov. "Increasing the efficiency of bactericide use when using seawater in a reservoir pressure maintenance system". Kazakhstan journal for oil & gas industry 5, n.º 4 (21 de enero de 2024): 48–59. http://dx.doi.org/10.54859/kjogi108660.

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Rationale: Since 2018, at the Uzen oilfield, in order to study and control the microbiological contamination with sulfate-reducing bacteria (hereinafter referred to as SRB) of oilfield environment, full-scale bactericidal treatment and monitoring of the effectiveness of reagent use have been carried out. At the equipped control points, water samples are taken for the content of SRB cells before and after injection of the bactericide. Target: Reduce the intensity of sulfidogenesis at the oilfield and, as a consequence, the concentration of hydrogen sulfide in the associated gas. Materials and methods: Since the applied technology of injecting the bactericide in shock dosages did not allow achieving a stable reduction in the concentration of hydrogen sulfide, it was replaced by the technology of constantly injecting the bactericide into seawater at a dosage of 40 mg/l in an experimental mode. This technology showed low efficiency, hydrogen sulfide (H2S) concentrations varied between 352–379 ppm, and the monthly consumption of the reagent increased by 40%. Based on the obtained data on ineffectiveness, the constant injection of bactericide at MPS-4 was stopped and a new technology for injection of bactericide was proposed, aimed at suppressing not only planktonic, but also adherent forms of SRB. Results: Results. Injection of the bactericide using the new technology showed significant efficiency, which was assessed by reducing the concentration of hydrogen sulfide in the associated gas by an average of 45% across the oilfield. Conclusion: The proposed new technology for injecting a bactericide made it possible to effectively suppress the activity of sulfidogenic microorganisms and reduce the level of biogenic hydrogen sulfide in the oilfield.

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8

Zhao, Jinghua, Ming Zhang, Yue Li, Zhiheng Zhang, Mingzi Chen, Tao Liu, Jiantao Zhang y Anshan Shan. "Therapeutic effect of hydrogen injected subcutaneously on onion poisoned dogs". Journal of Veterinary Research 61, n.º 4 (1 de diciembre de 2017): 527–33. http://dx.doi.org/10.1515/jvetres-2017-0068.

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AbstractIntroduction: The purpose of this study was to investigate the therapeutic effect of hydrogen on the therapy of onion poisoned dogs.Material and Methods: A total of 16 adult beagle dogs were divided into two groups (control and hydrogen) and all were fed dehydrated onion powder at the dose of 10 g/kg for three days. The dogs of the experimental group were given subcutaneous injection of 0.2 mL/kg of hydrogen for 12 days after making the poisoned model successful. Blood samples were collected before feeding onions, one day before injecting hydrogen, and 2 h after the injection of hydrogen on days 1, 3, 5, 7, 9, and 12. Control dogs were not treated with hydrogen.Results: The levels of leukocyte production, anaemia, red blood cell degeneration which was reflected by the values of Heinz body count, haemolytic ratio, and oxidative products in hydrogen treated group were lower than in control dogs on some days. The capacity of medullary haematopoiesis that was based on reticulocyte counts, and the antioxidation in hydrogen group were higher compared with control group. However, the differences in renal function were not obvious in both groups.Conclusion: Accordingly, it was concluded that subcutaneous injection of hydrogen could alleviate the symptoms in onion poisoned dogs.

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9

Jaworowski, A. E. "Spontaneous Hydrogen Injection into Silicon". Materials Science Forum 38-41 (enero de 1991): 1057–62. http://dx.doi.org/10.4028/www.scientific.net/msf.38-41.1057.

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10

Aghahasani, Mahdi, Ayat Gharehghani, Amin Mahmoudzadeh Andwari, Maciej Mikulski, Apostolos Pesyridis, Thanos Megaritis y Juho Könnö. "Numerical Study on Hydrogen–Gasoline Dual-Fuel Spark Ignition Engine". Processes 10, n.º 11 (1 de noviembre de 2022): 2249. http://dx.doi.org/10.3390/pr10112249.

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Hydrogen, as a suitable and clean energy carrier, has been long considered a primary fuel or in combination with other conventional fuels such as gasoline and diesel. Since the density of hydrogen is very low, in port fuel-injection configuration, the engine’s volumetric efficiency reduces due to the replacement of hydrogen by intake air. Therefore, hydrogen direct in-cylinder injection (injection after the intake valve closes) can be a suitable solution for hydrogen utilization in spark ignition (SI) engines. In this study, the effects of hydrogen direct injection with different hydrogen energy shares (HES) on the performance and emissions characteristics of a gasoline port-injection SI engine are investigated based on reactive computational fluid dynamics. Three different injection timings of hydrogen together with five different HES are applied at low and full load on a hydrogen–gasoline dual-fuel SI engine. The results show that retarded hydrogen injection timing increases the concentration of hydrogen near the spark plug, resulting in areas with higher average temperatures, which led to NOX emission deterioration at −120 Crank angle degree After Top Dead Center (CAD aTDC) start of injection (SOI) compared to the other modes. At −120 CAD aTDC SOI for 50% HES, the amount of NOX was 26% higher than −140 CAD aTDC SOI. In the meanwhile, an advanced hydrogen injection timing formed a homogeneous mixture of hydrogen, which decreased the HC and soot concentration, so that −140 CAD aTDC SOI implied the lowest amount of HC and soot. Moreover, with the increase in the amount of HES, the concentrations of CO, CO2 and soot were reduced. Having the HES by 50% at −140 CAD aTDC SOI, the concentrations of particulate matter (PM), CO and CO2 were reduced by 96.3%, 90% and 46%, respectively. However, due to more complete combustion and an elevated combustion average temperature, the amount of NOX emission increased drastically.

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11

Kim, Chae-Hyoung y In-Seuck Jeung. "Forced Combustion Characteristics Related to Different Injection Locations in Unheated Supersonic Flow". Energies 12, n.º 9 (8 de mayo de 2019): 1746. http://dx.doi.org/10.3390/en12091746.

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This work focuses on forced combustion with regards to the relationship between vent mixer models and several injection locations in unheated supersonic flow. A plasma jet torch was used to ignite the hydrogen-air mixture in a laboratory-scaled combustor duct. The flow field of the combustion was visualized with pressure and gas-sampling measurements. The vent mixers indicate good dispersion characteristics of the mixture for both parallel and normal 1 injections. However, forced combustion is dominantly governed by the injection rate toward the plasma jet (hot source) because the combustible region is restricted under the cold main flow. For this reason, the parallel injection, which provides the hydrogen-air mixture directly toward the plasma jet, shows good combustion performance. The normal 1 injection interacted with the vent mixers and shows slightly good combustion performance. Lastly, the normal 2 injection is little affected by the vent mixers and has poor combustion performance.

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12

Petito, C. K., R. P. Kraig y W. A. Pulsinelli. "Light and Electron Microscopic Evaluation of Hydrogen Ion-Induced Brain Necrosis". Journal of Cerebral Blood Flow & Metabolism 7, n.º 5 (octubre de 1987): 625–32. http://dx.doi.org/10.1038/jcbfm.1987.115.

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Excessive accumulation of hydrogen ions in the brain may play a pivotal role in initiating the necrosis seen in infarction and following hyperglycemic augmentation of ischemic brain damage. To examine possible mechanisms involved in hydrogen ion-induced necrosis, sequential structural changes in rat brain were examined following intracortical injection of sodium lactate solution (pH 4.5), as compared with injections at pH 7.3. Following pH 7.3 injection, neuronal swelling developed between 1 and 6 h, but only a needle track wound surrounded by a thin rim of necrotic neurons and vacuolated neuropil was present 24 h after injection. In contrast, pH 4.5 injection produced neuronal necrosis as soon as 1 h after injection, followed by necrosis of astrocytes and intravascular thrombi at 3 and 6 h. Alterations common to both groups included vascular permeability to horseradish peroxidase, dilation of extracellular spaces, astrocyte swelling, capillary compression, and vascular stasis. These data suggest that neurons, astrocytes, and endothelia can be directly damaged by increased acid in the interstitial space. Lethal injury initially appeared to affect neurons, while subsequent astrocyte necrosis and vascular occlusion may damage tissue by secondary ischemia.

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13

Shaikh, Sardar M. y S. V. Khandal. "Studies on Biodiesel and Hydrogen Powered Dual Fuel Common Rail Direct Injection Engine". Indian Journal Of Science And Technology 17, n.º 10 (1 de marzo de 2024): 917–23. http://dx.doi.org/10.17485/ijst/v17i10.3194.

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Objectives: To evaluate the effect of hydrogen and used temple oil biodiesel (BTO) combination on the performance of Common Rail Direct Injection (CRDi) engine. To report the maximum possible flow rate (HFR) for knock free operation of the engine at a speed of 1500 RPM. Methods: Transesterification process was used to get BTO. was inducted through intake manifold. BTO was injected into engine cylinder using electronically controlled technique. Findings: The study revealed that the peak HFR was for BTO and 0.24 for diesel at an Injection Pressure (IP) of 800 bar and Injection Timing (IT) of before top dead center (bTDC). The Dual Fuel (DF) CRDi engine with Toriodal Reentrant Combustion Chamber (TRCC) shape yielded 6% to lower Brake Thermal Efficiency (BTE) with reduced exhaust gas emissions except 19 to higher oxides of nitrogen (NOx) at and 100% loads. Both Peak Combustion Pressure (PP) and Heat Release Rate (HRR) were 5 to 9% higher than BTO run diesel engine operation. Combustion Duration (CD) and Ignition Delay (ID) were 6 to 15% lower in DF CRDi operation with . Novelty: Diesel engine comes with hemispherical combustion chamber (HCC). Toriodal Reentrant Shaped Combustion Chamber (TRCC) was adopted in place of HCC which results better mixing of air and fuel. and BTO combination was used to power CRDi engine. Electronically controlled fuel injection system developed and fitted to conventional diesel engine. Keywords: Used temple oil biodiesel (BTO); Common rail direct injection (CRDi) engine; Toriodal reentrant combustion chamber (TRCC); Hydrogen flow rate (HFR); Hydrogen-biodiesel energy ratio (H2BER)

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14

Guo, Shuman, Zhichao Lou, Xu Zhang, Shaokai Shen, Jintao Meng, Jiaqi Wang y Chunjian Zhou. "Optimizing Hydrogen and Ammonia Injection Timing for Enhanced Mixture Formation in Internal Combustion Engines". Journal of Engineering Research and Reports 26, n.º 4 (26 de marzo de 2024): 152–64. http://dx.doi.org/10.9734/jerr/2024/v26i41122.

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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.

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Liu, Min, Bo Zhao, Yaze Li, Zhen Wang, Xuesong Zhang, Liang Tong, Tianqi Yang, Xuefang Li y Jinsheng Xiao. "Parametric Study on Fin Structure and Injection Tube in Metal Hydride Tank Packed with LaNi5 Alloy for Efficient and Safe Hydrogen Storage". Sustainability 15, n.º 12 (18 de junio de 2023): 9735. http://dx.doi.org/10.3390/su15129735.

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Efficient hydrogen storage methods are crucial for the large-scale application of hydrogen energy. This work studied the effects of fin structure and injection tube on the system performance of a hydrogen storage tank packed with LaNi5 alloy. An axisymmetric finite element model of the metal hydride hydrogen storage tank was established. The fin structure and injection tube were added to the hydrogen storage tank, and the effects of the fin location and injection tube on the efficiency and safety of the hydrogen storage tank during hydriding were analyzed. A parametric study on the wall fin structure and injection tube has been carried out to optimize the design of a hydrogen storage tank, and to improve its efficiency and safety. The hydrogen storage capacity of the optimized tank packed with LaNi5 alloy can reach 1.312 wt%, which is 99% of its maximum capacity, at around 650 s. The results show that the fin structure can improve the heat transfer performance of the storage tank, and that the injection tube can enhance the mass transfer of hydrogen in the tank.

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16

K., Udaya Sri, B. S. N. Murthy y N. Mohan Rao. "Monitoring Exhaust Emissions of A Direct Injection Diesel Engine Fueled With Linseed Oil Biodiesel - Hydrogen Dual Fuel". International Journal of Innovative Technology and Exploring Engineering 10, n.º 6 (30 de abril de 2021): 42–49. http://dx.doi.org/10.35940/ijitee.f8765.0410621.

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This study presents an experimental and analytical investigation on the effects of using methyl ester of linseed oil (MELO)-diesel blend of B10, B20, and B30 with hydrogen injection of 5%, 10%, and 15% in a VCR (Variable Compression Ratio) diesel engine, operated with the compression ratios (CRs) of 15, 16, 17, and 18 on DFM (duel fuel mode). This study also gives emphasis on the optimized emissions of CO, CO2 , NO, and smoke, when the engine was operated with MELO-diesel blends, and hydrogen injections with the variation in engine load, crank angle (CA), using response surface methodology (RSM) with the help of MINITAB programming. During the analysis it was observed that the emissions of CO, CO2 , O2 , NO, and smoke were found to be a function of biodiesel blends, compression ratios, load, and percentage of hydrogen injection. The research results report that, the dual fuel mode of diesel MELO 20% blend with hydrogen injection of about 10% gave optimized results in terms of performance and exhaust emissions, while the optimized CR was 17. The engine was smoothly operated with B20-H10-CR17 over lower emissions compared to diesel, throughout the load spectrum.

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Rahantamialisoa, F. N. Z., J. Zembi, A. Miliozzi, N. Sahranavardfard y M. Battistoni. "CFD simulations of under-expanded hydrogen jets under high-pressure injection conditions". Journal of Physics: Conference Series 2385, n.º 1 (1 de diciembre de 2022): 012051. http://dx.doi.org/10.1088/1742-6596/2385/1/012051.

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Abstract Large-eddy simulations (LES) of hydrogen jets under highly under-expanded conditions are carried out. Computational fluid dynamics (CFD) analysis appears extremely useful to fully understand and optimize the hydrogen injection process, like in internal combustion engines. This work aims to analyze hydrogen high-pressure injection in the near-nozzle region, investigating the formation process and the structure of the Mach disks and the transition to turbulent jets, for nozzle pressure ratios (NPR) of 5.8 and 30. A real fluid model is utilized and compared against the simpler ideal gas model, for injections into an ambient pressure environment. Furthermore, hydrogen-air mixing evolution is investigated in the far-field region. Average quantities obtained from statistical analysis on LES simulations are compared with available data. The near nozzle region, except for the initial transient part, is better captured by accurate spatial discretization methods, while properly predicting far-field effects, like turbulence and acoustic effects, seems to be mostly related to time discretization schemes.

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Prokopowicz, Wojciech y Andrzej Frąckowiak. "A proposal of a hydrogen injection system in to a miniature turbojet engine". Journal of Konbin 53, n.º 1 (31 de marzo de 2023): 79–94. http://dx.doi.org/10.5604/01.3001.0016.3240.

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The solution proposed in this article, based on direct injection of hydrogen into the combustion chamber, offers many benefits, including a better volumetric efficiency, complete combustion (avoidance of premature ignition and backfire) and significant benefits in terms of power density when compared to engines, in which hydrogen is injected into the air inlet duct. The article discusses advantages and disadvantages of systems responsible for injecting hydrogen into the combustion chamber based on the operational phases of the GTM 400 engine developed by the JET-POL Company. The use of an electronic controller combined with an injector placed in an appropriate place inside the combustion chamber allow for the mentioned engine to be modified this way to optimize its power, performance and emissions. The article discusses matters related to challenges faced by materials used to make components of hydrogen injectors as well as research on the topic in question with the use of diesel engines. The article considers the impact of a low mass density and hydrogen energy, high speed of sound and low thickness on the injection system and components of a miniature turbojet engine. Physical attributes shaped by hydrogen fuel directly affect the size of components, selection of materials and tribology of turbojet engines. The authors suggest that the solutions used in the research on the GTM 400 engine can be used in the future to build hydrogen systems (hydrogen injection, storage and distribution) for fullscale passenger aircraft jet engines.

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Ding, Weiqi, Jun Deng, Chenxu Wang, Renjie Deng, Hao Yang, Yongjian Tang, Zhe Ma y Liguang Li. "Operating and Thermal Efficiency Boundary Expansion of Argon Power Cycle Hydrogen Engine". Processes 11, n.º 6 (19 de junio de 2023): 1850. http://dx.doi.org/10.3390/pr11061850.

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The efficiency enhancement of argon power cycle engines through theoretical means has been substantiated. However, the escalation of in-cylinder temperatures engenders abnormal combustion phenomena, impeding the augmentation of compression ratios and practical efficiency. This study presents a comprehensive investigation employing experimental and simulation techniques, aiming to extend the boundaries of thermal efficiency and operational capabilities for hydrogen-powered argon cycle engines. The impact of hydrogen direct injection, intake boost, and port water injection is evaluated in conjunction with an argon power cycle hydrogen engine. The hydrogen direct injection, particularly at an engine speed of 1000 rpm, significantly increases the indicated mean effective pressure from 0.39 MPa to 0.72 Mpa, surpassing the performance of the port hydrogen injection. Manipulating the hydrogen direct injection timing results in the formation of a stratified mixture, effectively attenuating the combustion rate, and resolving the issue of excessively rapid hydrogen combustion within an Ar/O2 environment. The implementation of super lean combustion, combined with intake-boosting, achieves a maximum gross indicated thermal efficiency of 57.89%. Furthermore, the port water injection proves to be an effective measure against knock, broadening the operational range of intake-boosted conditions. Notably, the maximum gross indicated thermal efficiency recorded for the port water injection group under intake-boosted conditions reaches 59.35%.

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Hu, Zhen, Shuang Yuan, Hong Wei, Zeyuan Huang, Haiqiao Wei, Siew Hwa Chan y Lei Zhou. "High-pressure injection or low-pressure injection for a direct injection hydrogen engine?" International Journal of Hydrogen Energy 59 (marzo de 2024): 383–89. http://dx.doi.org/10.1016/j.ijhydene.2024.02.018.

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21

Cheng, Xie, Sun Baigang y Han Zhen. "Investigation on Jet Characteristics of Hydrogen Injection and Injection Strategy for Backfire Control in a Port Fuel Injection Hydrogen Engine". Energy Procedia 105 (mayo de 2017): 1588–99. http://dx.doi.org/10.1016/j.egypro.2017.03.508.

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22

Huang, Zeyuan, Shuang Yuan, Hong Wei, Lijia Zhong, Zhen Hu, Zongkuan Liu, Changwen Liu, Haiqiao Wei y Lei Zhou. "Effects of hydrogen injection timing and injection pressure on mixture formation and combustion characteristics of a hydrogen direct injection engine". Fuel 363 (mayo de 2024): 130966. http://dx.doi.org/10.1016/j.fuel.2024.130966.

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23

Niethammer, Bernd, Christian Mayer, Thomas Claus y Christoph Weber. "Direct Injection for Hydrogen Combustion Engines". MTZ worldwide 83, n.º 11 (14 de octubre de 2022): 28–33. http://dx.doi.org/10.1007/s38313-022-0846-0.

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24

Dober, Gavin, Guy Hoffmann, Laurent Doradoux y Guillaume Meissonnier. "Direct Injection Systems for Hydrogen Engines". MTZ worldwide 82, n.º 12 (12 de noviembre de 2021): 60–65. http://dx.doi.org/10.1007/s38313-021-0720-5.

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25

Christensen, Lise y Vibeke Breiting. "COMPLICATIONS INDUCED BY POLYACRYLAMIDE HYDROGEN INJECTION". Plastic and Reconstructive Surgery 116, n.º 4 (septiembre de 2005): 1168–69. http://dx.doi.org/10.1097/01.prs.0000183381.64271.85.

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Adilson de Castro, Jose, Giulio Antunes de Medeiros, Elizabeth Mendes de Oliveira, Marcos Flavio de Campos y Hiroshi Nogami. "The Mini Blast Furnace Process: An Efficient Reactor for Green Pig Iron Production Using Charcoal and Hydrogen-Rich Gas: A Study of Cases". Metals 10, n.º 11 (11 de noviembre de 2020): 1501. http://dx.doi.org/10.3390/met10111501.

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The mini blast furnace process is an efficient route to produce pig iron based on the burden with granulated charcoal. New, improved technologies have recently been introduced in the mini blast furnace process, such as pulverized charcoal and gas injections, new burden materials, and peripheral devices that improve the overall process efficiency. In this paper, we revise the new injection possibilities and discuss new aspects for further developments. The analysis is carried out with a comprehensive multiphase multicomponent mathematical model using mass, momentum, and energy conservation principles coupled with the rate equations for chemical reactions, multiphase momentum, and heat exchanges. We analyze new technological possibilities for the enhancement of this process as follows: (i) a base case of pulverized charcoal injection with industrial data comparison; (ii) a set of scenarios with raceway injections, combining pulverized charcoal with hydrogen-rich fuel gas, replacing granular charcoal in the burden; (iii) a set of scenarios with hydrogen-rich gas injection at the shaft level, replacing reducing gas in the granular zone of the reactor; and the possible combination of both methodologies. The simulated scenarios showed that a considerable decrease in granular charcoal consumption in the burden materials could be replaced by combining a pulverized charcoal injection of 150 kg/tHM and increasing rich gas injections and oxygen enrichment values, decreasing the specific blast injection and granular charcoal. The productivity of the mini blast furnace process was increased for all scenarios compared with the reference case. We review the aspects of these operational conditions and present an outlook for improvements on the process efficiency.

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27

Li, Guanting, Xiumin Yu, Ping Sun y Decheng Li. "Study on the Effect of Second Injection Timing on the Engine Performances of a Gasoline/Hydrogen SI Engine with Split Hydrogen Direct Injecting". Energies 13, n.º 19 (7 de octubre de 2020): 5223. http://dx.doi.org/10.3390/en13195223.

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Split hydrogen direct injection (SHDI) has been proved capable of better efficiency and fewer emissions. Therefore, to investigate SHDI deeply, a numerical study on the effect of second injection timing was presented at a gasoline/hydrogen spark ignition (SI) engine with SHDI. With an excess air ratio of 1.5, five different second injection timings achieved five kinds of hydrogen mixture distribution (HMD), which was the main factor affecting the engine performances. With SHDI, since the HMD is manageable, the engine can achieve better efficiency and fewer emissions. When the second injection timing was 105° crank angle (CA) before top dead center (BTDC), the Pmax was the highest and the position of the Pmax was the earliest. Compared with the single hydrogen direct injection (HDI), the NOX, CO and HC emissions with SHDI were reduced by 20%, 40% and 72% respectively.

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28

Sun, Bai-gang, Dong-sheng Zhang y Fu-shui Liu. "Pressure fluctuations in a hydrogen supply system during hydrogen injection". International Journal of Hydrogen Energy 38, n.º 25 (agosto de 2013): 11156–63. http://dx.doi.org/10.1016/j.ijhydene.2013.02.122.

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29

Lamas, M. I. y C. G. Rodriguez. "NOx Reduction in Diesel-Hydrogen Engines Using Different Strategies of Ammonia Injection". Energies 12, n.º 7 (1 de abril de 2019): 1255. http://dx.doi.org/10.3390/en12071255.

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In order to reduce NOx emissions in internal combustion engines, the present work analyzes a measurement which consists of injecting ammonia directly into the combustion chamber. A commercial compression ignition engine fueled with a hydrogen-diesel blend was studied numerically. It was verified that the flow rate shape in which the ammonia was injected, particularly rectangular, triangular, or parabolic, as well as the injection duration had an important influence on NOx reduction. A 11.4% improvement in NOx reduction, corresponding to an overall reduction of 78.2% in NOx, was found for parabolic injection shape and 1º injection duration. The effect on carbon dioxide, carbon monoxide, and hydrocarbon emissions, as well as brake-specific consumption, was negligible.

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30

Caricato, Antonio, Antonio Paolo Carlucci, Antonio Ficarella y Luciano Strafella. "Effect of hydrogen addition in diesel/natural gas dual-fuel combustion with late injection". E3S Web of Conferences 312 (2021): 08005. http://dx.doi.org/10.1051/e3sconf/202131208005.

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In a previous work, the effectiveness of late pilot injection on improving combustion behaviour – in terms of fuel conversion efficiency and pollutant emission levels – in a diesel/natural gas dual-fuel engine was assessed. Then, an additional set of experiments was performed, aiming at speeding up the combustion process possibly without penalizing NOx levels. Therefore, hydrogen was added to natural gas in a percentage equal to 10%. Results show that hydrogen addition has a significant effect on the combustion development specially during the early stage of combustion: ignition delay is shortened and combustion centre is advanced, while the combustion duration increases when pilot injection timing is set to conventional values, while remains basically unchanged for late timings. Fuel conversion efficiency is only slightly penalized when hydrogen is added. Moreover, it was confirmed that, in general, combustion strategy with late pilot injection timing does not penalize fuel conversion efficiency; indeed, in some cases, it actually increases. Concerning regulated emission levels, it is again proven that late pilot injection does not penalize pollutant production: the hydrocarbons and carbon monoxide reduce as pilot injection is delayed, probably due to the higher temperatures reached into the cylinder during most part of the expansion stroke. Moreover, adding hydrogen always reduces their levels. Concerning NOx, they are drastically reduced delaying pilot injection; as expected, hydrogen addition promotes NOx formation, but the increase, evident with conventional pilot injection timings, becomes marginal with late injection strategy. Therefore, combustion strategy performance with late pilot injection in dual-fuel diesel/natural gas combustion conditions can be further improved with 10% hydrogen addition to natural gas.

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31

Wang, Xi, Bai-gang Sun, Qing-he Luo, Ling-zhi Bao, Jian-ye Su, Jie Liu y Xiang-chao Li. "Visualization research on hydrogen jet characteristics of an outward-opening injector for direct injection hydrogen engines". Fuel 280 (noviembre de 2020): 118710. http://dx.doi.org/10.1016/j.fuel.2020.118710.

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32

Jeong, Eunju, Sean O’Byrne, In-Seuck Jeung y A. F. P. Houwing. "The Effect of Fuel Injection Location on Supersonic Hydrogen Combustion in a Cavity-Based Model Scramjet Combustor". Energies 13, n.º 1 (1 de enero de 2020): 193. http://dx.doi.org/10.3390/en13010193.

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Supersonic combustion experiments were performed using three different hydrogen fuel-injection configurations in a cavity-based model scramjet combustor with various global fuel–air equivalence ratios. The configurations tested were angled injection at 15° to the flow direction upstream of the cavity, parallel injection from the front step, and upstream injection from the rear ramp. Planar laser-induced fluorescence of the hydroxyl radical and time-resolved pressure measurements were used to investigate the flow characteristics. Angled injection generated a weak bow shock in front of the injector and recirculation zone to maintain the combustion as the equivalence ratio increased. Parallel and upstream injections both showed similar flame structure over the cavity at low equivalence ratio. Upstream injection enhanced the fuel diffusion and enabled ignition with a shorter delay length than with parallel injection. The presence of a flame near the cavity was determined while varying the fuel injection location, the equivalence ratio, and total enthalpy of the air flow. The flame characteristics agreed with the correlation plot for the stable flame limit of non-premixed conditions. The pressure increase in the cavity for reacting flow compared to non-reacting flow was almost identical for all three configurations. More than 300 mm downstream of the duct entrance, averaged pressure ratios at low global equivalence ratio were similar for all three injection configurations.

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33

Ali, M. y T. Fujiwara. "A numerical study on the mixing of air and hydrogen in a scramjet combustor". Aeronautical Journal 109, n.º 1097 (julio de 2005): 325–35. http://dx.doi.org/10.1017/s0001924000000774.

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Abstract A numerical study on mixing of air and hydrogen is performed by solving two-dimensional full Navier-Stokes equations. The main stream is air of Mach 5 entering through the configured inlet of the combustor and gaseous hydrogen is injected from the configured jet on the side wall. Supersonic mixing and diffusion mechanisms of a transverse hydrogen jet in two-dimensional finite air streams have been analyzed and discussed. The computed results are compared with the experimental data and show good agreement. For an otherwise fixed combustor geometry, the air inlet width and injection angle are varied to study the physics of mixing and flow field characteristics. On the effect of inlet width variation, two competing phenomena have been observed: (i) upstream of injector the strength of recirculation is higher for wider inlet and consequently the mixing increases, and (ii) downstream, the diffusion of hydrogen decreases with the increase of inlet width and eventually mixing decreases. As a result, in far downstream the mixing efficiency increases up to certain inlet width and then decreases for further increment of inlet width. For the variation of injection angle results show that upstream of injector the mixing is dominated by recirculation and downstream the mixing is dominated by mass concentration of hydrogen. Upstream recirculation is dominant for injecting angle 60° and 90°. Incorporating the various effects, perpendicular injection shows the maximum mixing efficiency and its large upstream recirculation region has a good flame holding capability.

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34

Xue, Yun, Hai Quan Cao y Xue Cheng Lu. "A Study of a Hydrogen Enriched LPG Intake Liquid Injection Engine". Applied Mechanics and Materials 291-294 (febrero de 2013): 1901–4. http://dx.doi.org/10.4028/www.scientific.net/amm.291-294.1901.

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Review is made of research on LPG engine and hydrogen fueled or enriched engine. Based on the positive features of hydrogen and the current limitations associated with the LPG intake liquid injection engine, a hydrogen enriched LPG intake liquid injection engine was developed, and its performance and exhaust emission characteristics are investigated.

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35

Wu, Taoyang, Jixu Liu, Chunling Wu, Xiaojun Jing, Jiajia Liu, Guomin Pang, Xiangyang Guo y Yachen Guo. "Experimental study on the factors influencing performance and emissions of hydrogen internal combustion engines". E3S Web of Conferences 522 (2024): 01009. http://dx.doi.org/10.1051/e3sconf/202452201009.

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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.

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36

Tsumori, K., K. Ikeda, M. Kisaki, H. Nakano, K. Nagaoka, Y. Fujiwara, S. Kamio y M. Osakabe. "Challenges toward improvement of deuterium-injection power in the Large Helical Device negative-ion-based NBIs". Nuclear Fusion 62, n.º 5 (15 de marzo de 2022): 056016. http://dx.doi.org/10.1088/1741-4326/ac2d59.

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Abstract Improvement of deuterium injection power in the negative-ion-based NBIs (n-NBIs) for the Large Helical Device (LHD) are reported. Co-extracted electron current at acceleration of deuterium negative ions (D− ions) limits the injection power. The electron current is reduced by decreasing the extraction gap, and the injected D− current evaluated from the injection power increased from 46 to 55 A. Greater electron reduction was achieved by installing a structure named an ‘electron fence’ (EF), with which D− beam power was successfully improved from 2.0 MW to 3.0 MW. The injection power in three configurations − without EF, with EF of 5 mm and 7 mm distance from the plasma grid (PG) surface − have been compared in both cases of hydrogen and deuterium operations, and it was found that the configuration with the EF of 5 mm distance was the best to satisfy the performance for both of hydrogen and deuterium injections. Although the co-extracted electron current is reduced in the negative ion sources applied for JT-60SA and ITER by utilizing the PG filter, it is possible to achieve more effective electron reduction by combining the PG filter and the EF.

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37

Aytekin, Kürşad, Selma Şengiz Erhan, Züleyha Erişgin, Cem Zeki Esenyel y Selçuk Takır. "Intra-articular injection of hydrogen sulfide decreased the progression of gonarthrosis". Canadian Journal of Physiology and Pharmacology 97, n.º 1 (enero de 2019): 47–54. http://dx.doi.org/10.1139/cjpp-2018-0574.

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Hydrogen sulfide (H2S) is found in both the plasma and synovial fluid of patients with gonarthrosis. In the present study, we investigated whether intra-articular injection of sodium hydrosulfide (NaSH) (1 mM, 30 μL), a H2S donor, might affect gonarthrosis in rats. Gonarthrosis was induced surgically in the left knees of rats and left for 6 weeks for the development of disease. Then, intra-articular injections of NaSH or methylprednisolone (1 mg/kg, 30 μL) were administered to rats. Half of each group was sacrificed at the end of the first day and the other half was sacrificed at the end of 4 weeks to evaluate early and later effects of injections on gonarthrosis. The injury induced by anterior cruciate ligament resection and medial meniscectomy in rats caused the development of gonarthrosis. As the duration lengthened after gonarthrosis induction, the progression of the disease continued. According to the modified Mankin Scoring System, intra-articular injection of NaSH histopathologically slowed the progression of gonarthrosis, whereas methylprednisolone was ineffective. In addition, NaSH decreased apoptosis in rat knees with gonarthrosis. Each treatment did not cause injury to healthy knees. Our results lead to the consideration that intra-articular NaSH administration may be effective in the progression of gonarthrosis.

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38

Saravanan, N. y G. Nagarajan. "An experimental investigation on performance, emissions, and combustion in a manifold injection for different exhaust gas recirculation flowrates in hydrogen—diesel dual-fuel operations". Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 222, n.º 11 (1 de noviembre de 2008): 2131–45. http://dx.doi.org/10.1243/09544070jauto921.

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Hydrogen is receiving considerable attention as an alternative fuel to replace the rapidly depleting petroleum-based fuels. Its clean burning characteristics help to meet the stringent emission norms. In this experimental investigation a single-cylinder diesel engine was converted to operate in hydrogen—diesel dual-fuel mode. Hydrogen was injected in the intake manifold and the diesel was injected directly inside the cylinder. The injection timing and the injection duration of hydrogen were optimized on the basis of performance and emissions. Best results were obtained with hydrogen injection at gas exchange top dead centre with an injection duration of 30° crank angle. The flowrate of hydrogen was optimized as 7.5l/min with optimized injection timing and duration. The optimized exhaust gas recirculation (EGR) flowrate was 20 per cent at 75 per cent load. The optimized timings were chosen on the basis of performance, emission, and combustion characteristics. The EGR technique was adopted in the hydrogen—diesel dual-fuel mode by varying the EGR flowrate from 0 per cent to 25 per cent in steps of 5 per cent. The maximum quantity of exhaust gases recycled during the test was 25 per cent (up to 75 per cent load); beyond that unstable combustion was observed with an increase in smoke. The brake thermal efficiency with 20 per cent EGR decreases by 9 per cent compared with diesel. The nitrogen oxide (NO x) emission in hydrogen manifold injection decreases by threefold with 20 per cent EGR operation at full load. The NO x emission tends to reduce drastically with increase in the EGR percentage at all load conditions owing to the increase in heat capacity of the exhaust gases. The smoke decreases by 80 per cent in the dual-fuel operation compared with diesel at 75 per cent load.

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39

Cardoso, Leonardo Máximo, Débora Simões de Almeida Colombari, José V. Menani, Glenn M. Toney, Deoclécio Alves Chianca y Eduardo Colombari. "Cardiovascular responses to hydrogen peroxide into the nucleus tractus solitarius". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 297, n.º 2 (agosto de 2009): R462—R469. http://dx.doi.org/10.1152/ajpregu.90796.2008.

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The nucleus tractus solitarius (NTS), a major hindbrain area involved in cardiovascular regulation, receives primary afferent fibers from peripheral baroreceptors and chemoreceptors. Hydrogen peroxide (H2O2) is a relatively stable and diffusible reactive oxygen species (ROS), which acting centrally, may affect neural mechanisms. In the present study, we investigated effects of H2O2 alone or combined with the glutamatergic antagonist kynurenate into the NTS on mean arterial pressure (MAP) and heart rate (HR). Conscious or anesthetized (urethane and α-chloralose) male Holtzman rats (280–320 g) were used. Injections of H2O2 (125 to 1500 pmol/40 nl) into the intermediate NTS of anesthetized rats evoked dose-dependent and transient hypotension (−18 ± 3 to −55 ± 11 mmHg) and bradycardia (−16 ± 5 to −116 ± 40 bpm). Injection of the catalase inhibitor 3-amino-1,2,4-triazole (100 nmol/40 nl) into the NTS also produced hypotension and bradycardia. Previous injection of the ionotropic l-glutamate receptor antagonist kynurenate (7 nmol/40 nl) attenuated by 48% the bradycardic response, without changing the hypotension evoked by H2O2 (500 pmol/40 nl) in anesthetized rats. The antioxidant l-ascorbate (600 pmol/80 nl) injected into the NTS attenuated the bradycardic (42%) and hypotensive (67%) responses to H2O2 (500 pmol/40 nl) into the NTS. In conscious rats, injection of H2O2 (50 nmol/100 nl) into the NTS also evoked intense bradycardia (−207 ± 8 bpm) and hypotension (−54 ± 6 mmHg) that were abolished by prior injection of kynurenate (7 nmol/100 nl). The results show that H2O2 into the NTS induces hypotension and bradycardia probably due to activation of glutamatergic mechanisms.

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40

Yasunaga, N., S. Furukawa, Y. Kawaai y J. Hirotsuji. "Investigation of radical reactions for efficiency improvement in ozone-hydrogen peroxide treatment". Water Science and Technology 43, n.º 2 (1 de enero de 2001): 205–12. http://dx.doi.org/10.2166/wst.2001.0091.

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It was verified by laboratory-scale experiments that the two-port ozone injection method was more advantageous for reaction efficiency in the ozone-hydrogen peroxide treatment than the conventional one-port ozone injection method under the condition of same ozone dose. The reason for this effectiveness was also investigated in detail by computer simulations in the wide range of the rate constant of OH radical reacting with TOC (kTOC). The laboratory-scale experiments revealed that the amount of TOC decomposed (δTOC) increased by up to 41% by the two-port injection method, indicating a 27% improvement in δO3/δTOC. A detailed investigation of these experimental results by computer simulations showed that by injecting ozone in two ports the amount of ozone consumed for the OH radical formation was increased more remarkably than that of ozone consumed for the radical chain reactions, and that the amount of OH radical reacting with TOC was increased more strikingly than that with ozone. Furthermore, it was found that the smaller the kTOC value within 105–109 M–1s–1 was, the more advantageous for the reaction efficiency the two-port injection method was.

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41

Zhang, Yi, Lihong Yang y Wei Huang. "Study on Hydrogen Flow and Heat Transfer in Underground Salt Cavern Hydrogen Storage". Journal of Physics: Conference Series 2599, n.º 1 (1 de septiembre de 2023): 012017. http://dx.doi.org/10.1088/1742-6596/2599/1/012017.

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Abstract Hydrogen energy is a green, low-carbon, widely used secondary energy with abundant sources, and is gradually becoming one of the important carriers of energy transformation. The safe and efficient storage of hydrogen energy is particularly important. Underground hydrogen storage technology has received widespread attention due to its large scale and low comprehensive cost. Salt cavern hydrogen storage has good sealing performance, stable structure, and flexible operation, making it the most promising choice for large-scale underground hydrogen storage. According to the thermodynamic characteristics of hydrogen, a heat transfer model of hydrogen flow in salt cavern hydrogen storage is established. Three operating conditions, namely, hydrogen injection, static state, and hydrogen production, are simulated and calculated, and the flow field characteristics of hydrogen under different operating conditions are determined, providing technical support for the research on the design of hydrogen injection and production schemes for salt cavern hydrogen storage.

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42

de Castro, Jose Adilson, Giulio Antunes de Medeiros, Leonardo Martins da Silva, Ivaldo Leão Ferreira, Marcos Flavio de Campos y Elizabeth Mendes de Oliveira. "A Numerical Study of Scenarios for the Substitution of Pulverized Coal Injection by Blast Furnace Gas Enriched by Hydrogen and Oxygen Aiming at a Reduction in CO2 Emissions in the Blast Furnace Process". Metals 13, n.º 5 (10 de mayo de 2023): 927. http://dx.doi.org/10.3390/met13050927.

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A numerical simulation procedure is proposed for analyzing the partial replacement of pulverized coal injection by hydrogen, oxygen, and blast furnace gas (BFG) injections mixed with pulverized coal (PCI) within the tuyeres of large blast furnaces. The massive use of hydrogen-rich gas is extremely interesting for ironmaking blast furnaces in the context of net-zero carbon hot metal production. Likewise, this new approach allows for increasing productivity and for reducing the specific emissions of carbon dioxide toward a net-zero carbon ironmaking technology. Nevertheless, the mixture of pulverized coal injection and gas injection is a complex technology. In addition to the impact on chemical reactions and energy exchange, the internal temperature and gas flow patterns can also change drastically. With a view to assessing the state of the furnace in this complex operation, a comprehensive mathematical model utilizing multiphase theory was developed. The model simultaneously handles bulk solids (sinter, pellets, small coke, granular coke, and also iron ore), gas, liquid metal and slag, and coal powder phases. The associated conservation equations take into account momentum, mass, chemical species, and energy while being discretized and solved using finite volume techniques. The numerical model was validated against the reference operating conditions using 220 kg per ton of pig iron (kg/tHM) of pulverized coal. Therefore, the combined injection of different concentrations of fuel hydrogen, blast furnace gas, and oxygen was simulated for replacing 40, 60, and 80 kg/tHM of coal injection. Theoretical analysis showed that the best scenario with stable operation conditions could be achieved with a productivity increase of 20% corresponding to a CO2 reduction of 15% and 60 kg/tHM of PCI replacement.

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43

Fan, Baowei, Jianfeng Pan, Yangxian Liu, Yuejin Zhu, Zhenhua Pan, Wei Chen y Peter Otchere. "Effect of hydrogen injection strategies on mixture formation and combustion process in a hydrogen direct injection plus natural gas port injection rotary engine". Energy Conversion and Management 160 (marzo de 2018): 150–64. http://dx.doi.org/10.1016/j.enconman.2018.01.034.

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44

Levin, V. A., N. E. Afonina, V. G. Gromov, I. S. Manuilovich y V. V. Markov. "Stabilization of combustion of kerosene-air mixture by hydrogen injection". BULLETIN of L.N. Gumilyov Eurasian National University. MATHEMATICS. COMPUTER SCIENCE. MECHANICS Series 134, n.º 1 (2021): 6–18. http://dx.doi.org/10.32523/2616-7182/2021-134-1-6-18.

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On aircrafts at high flight speeds, the ramjet engine (ramjet) is of greatest interest at present, the efficiency of which can be increased by using the thermochemical fuel conversion (TFC) technology. Some aspects of the operation of such an engine can be simulated numerically. In this work, a theoretical and experimental study of the processes in the combustion chamber is carried out, and a method is proposed for stabilizing the combustion of a keroseneair mixture by injecting molecular hydrogen into a direct-flow combustion chamber. An experimental setup created at TsAGI was used, on which the influence of the hydrogen temperature, the location and size of the mass supply area on the combustion process was studied. For a theoretical study, the corresponding numerical technology was applied based on the Navier-Stokes equations using the Spal-rt-Allmares turbulence model, implemented in a complex of computer programs developed at the Research Institute of Mechanics of Moscow State University. Numerical modeling solved two problems. The first concerned the conditions for the ignition of molecular hydrogen supplied to the flow-type igniter, and the second - the conditions for the stabilization of the combustion of a kerosene-air mixture by a hydrogen flame. Based on the results of calculations, it was found that the ignition process is facilitated by an increase in the temperature of hydrogen and the power of its injection. The position and size of the hydrogen source is less influential. In the course of a comprehensive study by the method of a full-scale and computational experiment, the characteristic features of the flow structure in the channel, including the formation of a detonation wave, were revealed, and the possibility of controlling combustion by hydrogen injection was shown.

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45

Geng, Qi, Xuede Wang, Yang Du, Zhenghao Yang, Rui Wang y Guangyu He. "Effect of the Hydrogen Injection Position on the Combustion Process of a Direct Injection X-Type Rotary Engine with a Hydrogen Blend". Energies 15, n.º 19 (1 de octubre de 2022): 7219. http://dx.doi.org/10.3390/en15197219.

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As a new type of power device, the X-type rotary engine (XRE) is regarded as a major revolution of the internal combustion engine with its special structure and high-efficiency hybrid cycle (HEHC). A 3D CFD model of an XRE with hydrogen–gasoline fuel is firstly built in this paper. The gasoline is premixed with air in the intake of the XRE. The hydrogen is directly injected (DI) into the cylinder with four different injection positions. The effects of the hydrogen injection position on the combustion process, engine thermodynamic performance, and unburned carbon emissions and NOx emissions are investigated. The results show that, due to the interaction between the in-cylinder main flow field and the injected hydrogen gas flow, different hydrogen concentration zones are formed at different injection positions. Furthermore, a larger hydrogen distribution area and being closer to the ignition position led to a faster in-cylinder combustion rate and a higher in-cylinder temperature and pressure. When the injection position is from the front to the back of the combustion chamber such as in position 2, the hydrogen has the widest distribution area and is closest to the ignition position, resulting in its fastest combustion speed. Meanwhile, the peak in-cylinder pressure is 3.73 MPa and the peak temperature is a maximum of 1835.16 K. Especially, the highest indicated thermal efficiency of 26.56% is found in position 2, which is 10.08% higher than that of position 4 (from right to left of the combustion chamber), which was 24.13%. At the same time, due to the best overall combustion effect, position 2 presents the lowest final unburned carbon emission of 0.36 mg, while it produces the highest NOx emission of 9.15 μg. Thus, this study provides important theoretical guidelines for the hydrogen injection strategy of the XRE using hydrogen–gasoline fuel.

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46

Lichtenbaum, Roger, Atos Alves de Souza y Jafar J. Jafar. "Intratumoral Hydrogen Peroxide Injection During Meningioma Resection". Operative Neurosurgery 59, suppl_4 (enero de 2006): ONS—470—ONS—473. http://dx.doi.org/10.1227/01.neu.0000233908.69004.95.

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Abstract OBJECTIVE: Meningiomas, although histologically benign, pose a particular challenge to the neurosurgeon because of their extensive and exuberant vascularity. They often bleed extensively during resection until separated from their blood supply. There are a wide variety of hemostatic agents available to the neurosur-geon. Most of these means of hemostasis involve some sort of chemical, electrical, or compressive action. Although anecdotally known to be useful, the use of hydrogen peroxide as an intracranial hemostatic agent in meningioma surgery has not been formally reported. We report a technique of meningioma resection that uses intratumoral hydrogen peroxide injection, reducing the potential for blood loss and shortening resection times. METHODS: Seventy-five patients underwent resection of a meningioma using the direct intratumoral H2O2 injection technique. The locations of these meningiomas included convexity and cranial-based lesions. None of the patients underwent preoperative endovascular embolization. RESULTS: The use of this technique greatly facilitated the removal of these tumors. No evidence of air embolism occurred during Doppler surveillance and no other significant side effects attributable to H2O2 application were observed. @@CONCLUSION:@@ We demonstrate a previously unreported technique of meningi-oma resection that uses direct intratumoral hydrogen peroxide injection, potentially reducing blood loss, shortening resection times, and obviating the need for preoperative embolization.

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47

Combs, S. K., S. L. Milora y C. R. Foust. "Simple pipe gun for hydrogen pellet injection". Review of Scientific Instruments 57, n.º 10 (octubre de 1986): 2636–37. http://dx.doi.org/10.1063/1.1139214.

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48

Woosley, J. P., R. J. Turnbull y K. Kim. "Field injection electrostatic spraying of liquid hydrogen". Journal of Applied Physics 64, n.º 9 (noviembre de 1988): 4278–84. http://dx.doi.org/10.1063/1.341301.

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49

Trostell, Bertil. "Vacuum injection of hydrogen micro-sphere beams". Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 362, n.º 1 (agosto de 1995): 41–52. http://dx.doi.org/10.1016/0168-9002(95)00302-9.

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50

Li, Yong, Wenzhi Gao, Pan Zhang, Yixiang Ye y Zhaoyi Wei. "Effects study of injection strategies on hydrogen-air formation and performance of hydrogen direct injection internal combustion engine". International Journal of Hydrogen Energy 44, n.º 47 (octubre de 2019): 26000–26011. http://dx.doi.org/10.1016/j.ijhydene.2019.08.055.

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