首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
Environmental crisis requires using cleaner energy sources for different sectors including the transportation. Hydrogen can support the transition of the automotive industry from petrol and diesel into a sustainable fuel. It could be the main source of energy or the auxiliary fuel in vehicles. As an auxiliary fuel, it has recently been considered in hydroxyl (HHO) form for reducing the emissions from transportation fleet. In this study, an HHO generator with the optimum power consumption was utilised for HHO injection into the intake manifold of a petrol engine as the case study. High concentration of CO is expected to be produced during idling, so the experiments were designed to inject ultra-low HHO for reducing CO emissions. The results were very promising, and it was shown that the CO emission could be reduced by about 98%. Furthermore, a novel design was developed based on the concept of waste heat recovery (WHR) for powering the HHO unit. Engine was simulated in AVL software to design a thermo-electric generators (TEG) for running the HHO unit. Based on the results, TEG can provide the energy required for HHO unit as the energy output of the TEG was between 91 kJ and 169 kJ for the case study while the energy consumption of the proposed HHO generator was just about 22.5 kJ. The results of this study are recommending a practical solution for bringing HHO injection from laboratory research into the real practice.  相似文献   

2.
As a hydrogen fuel for real-time production without storage, HHO has great research prospect and significance. In this paper, we conducted experiments on a spark ignition (SI) engine which has two independent fuel supply systems to compare two combination modes of gasoline port injection plus HHO (GPI + HHO) and gasoline direct injection plus HHO (GDI + HHO) at different HHO flow rate, λ, engine speed and load. The results show that, in both modes, HHO addition increases the maximum cylinder pressure and torque. With the increase of HHO flow rate, the flame development period and flame propagation period shorten, the crank angle corresponding to the maximum cylinder pressure is closer to top dead center. In addition, GDI + HHO mode has better engine performance. HHO has a significant effect on improving combustion stability. Especially at λ = 1.4, as HHO flow rate increases from 0 to 16 L/min, the coefficient of indicated mean effective pressure variation of GPI + HHO and GDI + HHO mode decreases by 69.17% and 58.29%, respectively. Moreover, HHO addition improves HC and CO emissions but increases NOx emissions. CO and HC emissions of GDI + HHO mode are the lowest under all conditions, and reaching the lowest value when HHO flow rate = 16 L/min. Besides, GDI + HHO mode not only has lower NO emissions under normal working conditions (λ = 1) but also can maintain a better combustion environment under lean-burn conditions (λ = 1.2, 1.4). In general, the application of HHO as fuel in engine can improve combustion and emission characteristics and GDI + HHO mode is the best combination of gasoline and HHO.  相似文献   

3.
The paper describes an experiment aimed at specifying the effects of adding Brown's gas (HHO gas) in automotive engines operating at idle speed. HHO gas was obtained from the author's parallel plate generator with a single central anode and two side cathodes separated by six neutral plates. The generator was powered by an external power source (power supply unit) and produced a constant HHO gas flow rate in the experiment. The so obtained HHO gas was added to the engine intake systems of 5 passenger cars – three SI engines, i.e. Fiat Cinquecento, Renault Twingo, and Opel Corsa and two CI engines, i.e. Skoda Octavia and Opel Combo. The engines operated in idling conditions. The MAHA MGT5 analyzer measured the concentrations of CO, HC, NOx in the exhaust gases of those cars first fueled by stock fuel (SF) only and then with added HHO gas, i.e. SF + HHO. The ambient conditions remained constant.The results show that fueling with an HHO gas additive has an impact on emissions: CO and HC concentrations in the exhaust gases were reduced in the most of the cases; NOx concentration was reduced in the SI engines but increased in the Diesel ones. Adding HHO gas to the engine intake system of the Fiat Cinquecento operating at idle slightly deteriorated the combustion process there (the impact of carburetor-based supply without feedback). Although HC concentration was lower by 24%, the amount of CO increased by 34% and nitrogen oxides hardly changed. CO concentration if any decreased in the other vehicles.The concentration of HC in the exhaust gases of each of the vehicles show that adding HHO gas to the original fuel, regardless of fueling methods and techniques, reduces the concentration of unburned hydrocarbons: by more than 20% in the Fiat and by about 40% in the others. The NOx concentration in the exhaust gases of each of the vehicles show that after adding HHO to the original fuel, the amount of NOx depends on a fueling method. In the SI engines with indirect injection, adding HHO gas to the intake system reduced the NOx concentration. In the Fiat with a carburetor without feedback, the NOx concentration remained practically unchanged but it increased in the CI engines if HHO gas was added to their intake systems.  相似文献   

4.
Today, the important challenges with the utilization of hydrogen in power-producing applications (internal combustion engines and fuel cells) are its delivery and storage and these create a big hesitation regarding the application safety. Ammonia, which can be regarded as the most promising alternative fuel to hydrogen, provides the possibility of storage in liquid form at low pressures and high temperatures. This study was carried out to investigate how to compensate the drawbacks of using ammonia as the main fuel in a gas turbine by hydrogen and hydroxy-gas enrichment. During the experiments, propane that is standard working fuel of the gas turbine, neat ammonia, as well as a 10 L/min ammonia fuel enriched with 3 L/min, 5 L/min, and 7 L/min hydroxy gas, were utilized. The results show that hydroxy enrichments cause improvements in the performance data as well as emission values due to the absence of any carbon emissions. When the performance outputs are examined, it has been shown that the power values of NH3 + 3 HHO and NH3 + 5 HHO fuels are 10.98% and 3.65% lower than propane, whereas NH3 + 7 HHO fuel produces 4.12% more power, and the desired performance values are reached. It has been also fund that NOx emissions should be kept under control in addition to the increase in the performance and elimination of the carbon emissions.  相似文献   

5.
Water electrolysis produces HHO gas by using sodium hydroxide catalyst. Dry and wet cells designs are applied producing the gas flow rates at 0.5 and 0.75 LPM, respectively. Tests are done in a diesel engine at engine speed variation and full load. Performance, combustion characteristics and emissions investigations of diesel engines using HHO gas from dry and wet cells are performed. HHO gas addition enhances the brake thermal efficiency by 2 and 2.5% but the exhaust gas temperature highest decreases for dry and wet cells are 8 and 10%, respectively about diesel oil. The maximum decreases are evaluated as for CO (15, 22%), HC (31, 39%), NOx (35, 42%) and smoke emissions (25, 35%), respectively for dry and wet cells about diesel fuel. The improvements in cylinder pressures are 5 and 10%, respectively and the heat release rate enhancements are 4.5 and 6.5%, respectively about pure diesel for dry and wet configurations.  相似文献   

6.
In this study, with the aim of reducing the energy consumption in the production of HHO gas for use in the combustion process of diesel fuel, different modes of gas production were investigated using electrolyzers. According to previous studies, the energy consumption rate of the electrolyzer to produce a high volumetric flow of HHO gas is very high. This high rate will restrict the use of equipment such as high-capacity batteries. The effects of HHO gas injection at the idle speed of the engine at a low temperature were evaluated. Because in this situation, the engine makes high air pollution. The results showed that the percentage of CO, CO2, HC, and NOX gases decreased by 66%, 33%, 38%, and 11%, respectively. On the other hand, the amount of O2 gas in the exhaust increased by 18%. These results were reported for HHO gas injection from 10 to 45 ml/s. The performance of Group Method of Data Handling (GMDH) neural network was desirable in modeling diesel engine pollutants. Because the Root-Mean-Square Error (RMSE) criterion for all evaluated gases is less than 0.32. The GMDH neural network was used for modeling the operation of the diesel engine with HHO supplemental fuel. The GMDH results showed that this artificial network can measure all engine exhaust gases. It can be used as a sensor and virtual simulator for this diesel engine with HHO supplemental fuel.  相似文献   

7.
Hydrogen and HHO enriched biodiesel fuels have not been investigated extensively for compression ignition engine. This study investigated the performance and emissions characteristics of a diesel engine fueled with hydrogen or HHO enriched Castor oil methyl ester (CME)-diesel blends. The production and blending of CME was carried out with a 20% volumetric ratio (CME20) using diesel fuel. In addition, the enrichment of intake air was carried out using pure HHO or hydrogen through the intake manifold with no structural changes – with the exception of the reduction of the amount of diesel fuel – for a naturally aspirated, four cylinder diesel engine with a volume of 3.6 L. Hydrogen amount was kept constant with a ratio of 10 L/min throughout the experiments. Engine performance parameters, including Brake Power, Brake Torque, Brake Specific Fuel Consumption and exhaust emissions – including NOx and CO, – were tested at engine speeds between 1200 and 2600 rpm. It is seen that HHO enriched CME has better results compared to pure hydrogen enrichment to CME. An average improvement of 4.3% with HHO enriched CME20 was found compared to diesel fuel results while pure hydrogen enriched CME20 fuel resulted with an average increase of 2.6%. Also, it was found that the addition of pure hydrogen to CME had a positive effect on exhaust gas emissions compared to that adding HHO. The effects of both enriched fuels on the engine performance were minimal compared to that of diesel fuel. However, the improvements on exhaust gas emissions were significant.  相似文献   

8.
In the present work, using the HydroBoost technology, performance and emission characteristics of HHO added Gasoline is investigated. HydroBoost technology offers longevity to cell and increases the efficiency as it requires less power to break the bonds of water. Achieving good emission characteristics using HydroBoost technology is still unexplored. In the present work, following the EPA protocols, a comprehensive analysis of Total Hydrocarbon (THC), Methane (CH4), NOx, CO2, MPG emissions in four phases is performed. It is shown that harmful gas emissions are reduced in HHO added Gasoline in comparison to only Gasoline fuel. The stoichiometric air-fuel mixture has been achieved in the present work. BSFC (Brake Specific Fuel Consumption) is reduced by up to 11% and the overall emissions of HHO added gasoline are reduced by up to 13% for CO2, up to 72% for Total Hydrocarbons, up to 69% for Methane, up to 48% for NOx in relation to bare Gasoline fuel. The present technology enables Hydroxy gas to be produced on board the IC vehicle without creating an undesirable amount of parasitic loss or hazard, which can be immediately deployed to lower both BSFC and emissions including greenhouse gasses such as CO2.  相似文献   

9.
The Neem-oil methyl ester (NME) produced from transesterification of Neem-oil was mixed with diesel fuel in the share of 10%(N10) and 20%(N20) were used with varying flow rate of oxy-hydrogen gas (HHO) gas at 5%,10% and 15% energy share along with exhaust gas recirculation (EGR) in a 3.7 kW CI engine. Presence of fuel-borne oxygen in NME, facilitates increase in brake thermal efficiency (BTE) at high load related to neat diesel operation. Further the BTE was improved by introducing varying flow rate of HHO gas in order to maintain energy share of 5, 10 and 15% at all loads. The BTE was found as 33.80% and 35.40% for N20 + 10%HHO and N20 + 15%HHO compared to 31.5%, 30.4% and 29.4% for N20, N10 and Neat diesel fuel respectively. Significant emission reduction of CO, CO2, uHC and smoke opacity were observed during NME + HHO gas operation, but NOx emission was augmented which was controlled using EGR along with further improvement in the engine characteristics.  相似文献   

10.
HHO gas, which is obtained by the electrolysis of water, is a promising alternative fuel. This paper presents a review of important features and techniques used for producing HHO gas. Various aspects of the thermodynamics and chemical kinetics of electrolysis reactions are discussed. Design and operating parameters for improving the gas production rate are identified. Widely different hypotheses regarding the structure and composition of HHO gas are compared in depth. The state of the art on the use of HHO gas in Internal Combustion (IC) engines is presented in the latter part of the paper. It is seen that the introduction of HHO gas increases engine torque, power and thermal efficiency, while simultaneously reducing the formation of NOx, CO, HC and CO2. The major challenges in using HHO gas in engines are identified as system complexity, safety, cost and efficiency of electrolysis.  相似文献   

11.
In this study, hydroxy gas (HHO) was produced by the electrolysis process of different electrolytes (KOH(aq), NaOH(aq), NaCl(aq)) with various electrode designs in a leak proof plexiglass reactor (hydrogen generator). Hydroxy gas was used as a supplementary fuel in a four cylinder, four stroke, compression ignition (CI) engine without any modification and without need for storage tanks. Its effects on exhaust emissions and engine performance characteristics were investigated. Experiments showed that constant HHO flow rate at low engine speeds (under the critical speed of 1750 rpm for this experimental study), turned advantages of HHO system into disadvantages for engine torque, carbon monoxide (CO), hydrocarbon (HC) emissions and specific fuel consumption (SFC). Investigations demonstrated that HHO flow rate had to be diminished in relation to engine speed below 1750 rpm due to the long opening time of intake manifolds at low speeds. This caused excessive volume occupation of hydroxy in cylinders which prevented correct air to be taken into the combustion chambers and consequently, decreased volumetric efficiency was inevitable. Decreased volumetric efficiency influenced combustion efficiency which had negative effects on engine torque and exhaust emissions. Therefore, a hydroxy electronic control unit (HECU) was designed and manufactured to decrease HHO flow rate by decreasing voltage and current automatically by programming the data logger to compensate disadvantages of HHO gas on SFC, engine torque and exhaust emissions under engine speed of 1750 rpm. The flow rate of HHO gas was measured by using various amounts of KOH, NaOH, NaCl (catalysts). These catalysts were added into the water to diminish hydrogen and oxygen bonds and NaOH was specified as the most appropriate catalyst. It was observed that if the molality of NaOH in solution exceeded 1% by mass, electrical current supplied from the battery increased dramatically due to the too much reduction of electrical resistance. HHO system addition to the engine without any modification resulted in increasing engine torque output by an average of 19.1%, reducing CO emissions by an average of 13.5%, HC emissions by an average of 5% and SFC by an average of 14%.  相似文献   

12.
Petroleum (Hydrocarbon – HC) based fuels are used for powering automotive and local power generation systems. Hydrocarbons on combustion produce gases such as CO2, CO, HC and NOx which affect human health as well as environment. Introduction of Hydrogen in Internal Combustion (IC) engine reduces emission and increases the performance. HHO gas which is produced through electrolysis of water can be used instead of hydrocarbon based fuels as the gas contains both Hydrogen as well as oxygen. Due to the challenges in storing Hydrogen, HHO gas is produced onsite through electrolysis process. This article presents the investigation on producing HHO gas through electrolysis onsite. A numerical calculation was done using empirical formula to predict the production of HHO gas. The electrolyser's performance analysis showed that maximum of 0.75 LPM of HHO gas was produced at 80 °C and by supplying 40 A-h. The numerical calculation showed that at the similar working condition the HHO gas produced was 1.3 LPM. The trend of both experiments and model was same for varying the current and rate of generation of HHO gas. This article also presents the effect of parameters such as concentration of electrolyte solution on potential, effect of time and the effect of temperature on production rate. The energy required and the number of modules or units of HHO gas production for real time engine application has been analysed and reported.  相似文献   

13.
Biomass producer gas presents a very promising alternative fuel to diesel since it is a renewable and clean burning fuel having similar properties to those of diesel. In this outline, a multi-cylinder diesel engine is experimentally optimized for maximum diesel savings, lower emissions, and without any excessive vibration of the engine using sawdust biomass as producer gas. Emission parameters of the double-fuel engine at diverse gas flow rates are contrasted with those of diesel at distinctive load conditions. The study brings out that the greatest diesel reserve happens to be 80% at 8 kW load without any engine issue in dual-fuel mode. Carbon monoxide (CO), hydrocarbon (HC), and carbon dioxide (CO2) emissions in dual-fuel mode are more contrasted with diesel at all test extents. Smoke opacity and oxide of nitrogen (NO) emission values in dual-fuel mode are less contrasted with diesel.  相似文献   

14.
This paper describes the potential applications of renewable energy sources to replace fossil fuel combustion as the prime energy sources in various countries, and discusses problems associated with biomass combustion in boiler power systems. Here, the term biomass includes organic matter produced as a result of photosynthesis as well as municipal, industrial and animal waste material. Brief summaries of the basic concepts involved in the combustion of biomass fuels are presented. Renewable energy sources (RES) supply 14% of the total world energy demand. RES are biomass, hydropower, geothermal, solar, wind and marine energies. The renewables are the primary, domestic and clean or inexhaustible energy resources. The percentage share of biomass was 62.1% of total renewable energy sources in 1995. Experimental results for a large variety of biomass fuels and conditions are presented. Numerical studies are also discussed. Biomass is an attractive renewable fuel in utility boilers. The compositions of biomass among fuel types are variable. Ash composition for the biomass is fundamentally different from ash composition for the coal. Especially inorganic constituents cause to critical problems of toxic emissions, fouling and slagging. Metals in ash, in combination with other fuel elements such as silica and sulfur, and facilitated by the presence of chlorine, are responsible for many undesirable reactions in combustion furnaces and power boilers. Elements including K, Na, S, Cl, P, Ca, Mg, Fe, Si are involved in reactions leading to ash fouling and slagging in biomass combustors. Chlorine in the biomass may affect operation by corrosion. Ash deposits reduce heat transfer and may also result in severe corrosion at high temperatures. Other influences of biomass composition are observed for the rates of combustion and pollutant emissions. Biomass combustion systems are non-polluting and offer significant protection of the environment. The reduction of greenhouse gases pollution is the main advantage of utilizing biomass energy.  相似文献   

15.
Energy security is an important consideration for development of future transport fuels. Among the all gaseous fuels hydrogen or hydroxy (HHO) gas is considered to be one of the clean alternative fuels. Hydrogen is very flammable gas and storing and transporting of hydrogen gas safely is very difficult. Today, vehicles using pure hydrogen as fuel require stations with compressed or liquefied hydrogen stocks at high pressures from hydrogen production centres established with large investments.Different electrode design and different electrolytes have been tested to find the best electrode design and electrolyte for higher amount of HHO production using same electric energy. HHO is used as an additional fuel without storage tanks in the four strokes, 4-cylinder compression ignition engine and two-stroke, one-cylinder spark ignition engine without any structural changes. Later, previously developed commercially available dry cell HHO reactor used as a fuel additive to neat diesel fuel and biodiesel fuel mixtures. HHO gas is used to hydrogenate the compressed natural gas (CNG) and different amounts of HHO-CNG fuel mixtures are used in a pilot injection CI engine. Pure diesel fuel and diesel fuel + biodiesel mixtures with different volumetric flow rates are also used as pilot injection fuel in the test engine. The effects of HHO enrichment on engine performance and emissions in compression-ignition and spark-ignition engines have been examined in detail. It is found from the experiments that plate type reactor with NaOH produced more HHO gas with the same amount of catalyst and electric energy. All experimental results from Gasoline and Diesel Engines show that performance and exhaust emission values have improved with hydroxy gas addition to the fossil fuels except NOx exhaust emissions. The maximum average improvements in terms of performance and emissions of the gasoline and the diesel engine are both graphically and numerically expressed in results and discussions. The maximum average improvements obtained for brake power, brake torque and BSFC values of the gasoline engine were 27%, 32.4% and 16.3%, respectively. Furthermore, maximum improvements in performance data obtained with the use of HHO enriched biodiesel fuel mixture in diesel engine were 8.31% for brake power, 7.1% for brake torque and 10% for BSFC.  相似文献   

16.
The main purpose of this study is to analyse the effects of oxy hydrogen (HHO) along with the Moringa oleifera biodiesel blend on engine performance, combustion and emission characteristics. HHO gases were generated using the typical electrolysis process using the potassium hydroxide solution. The experiments were performed under various engine loads of 25%, 50%, 75%, and 100% in a constant speed engine. Biodiesel from the M. oleifera was prepared by the transesterification process. Further, the procured biodiesel blends mixed with neat diesel at the concentration of 20% (B20) and 40% (B40). In addition to above, the HHO gas flow rate to the engine chamber maintained at the flow rate of 0.5 L-1. The use of the 20% and 40% blends with HHO reported less BTE compared to the neat diesel. However, B20 reported marginal rise in the BTE due to the addition of the HHO gas. On the other hand, addition of HHO gas to the blends significantly dropped the brake specific fuel consumption. With regard to the emissions, addition of the biodiesel blends reduced the concentration of the CO, HC, and CO2. Nevertheless, no reduction reported in the formation of the NO. However, adding the HHO to the biodiesel reduced the average NOx by 6%, which is a substantial effect. Overall, HHO enriching biodiesel blends are the potential replacement for the existing fossil fuels for its superior fuel properties compared to the conventional diesel.  相似文献   

17.
The present work is focused on the development of energy-efficient internal combustion engines with minimized CO, CO2, CH and NOx emissions. In frame of this concept, a method for hydrogen-rich gas generation onboard a vehicle and, in particular, its application as an additive to the engine fuel was suggested and tested experimentally. For practical realization of the method, the catalysts for hydrocarbon fuel reforming to synthesis gas were created, compact under-hood mounted synthesis gas generator was designed, and integrated ICE-synthesis gas generator control system was developed. The tests proved fuel economy in city cycle and considerable decrease of CO, CO2, CH and NOx emissions. The prospects of the technology for the development of energy-efficient environmentally benign engines are analyzed.  相似文献   

18.
Solid biomass materials are an important industrial fuel in many developing countries and also show good potential for usage in Europe within a future mix of renewable energy resources. The sustainable use of wood fuels for combustion relies on operation of plant with acceptable thermal efficiency. There is a clear link between plant efficiency and environmental impacts due to air pollution and deforestation. To supplement a somewhat sparse literature on thermal efficiencies and nitrogen oxide emissions from biomass-fuelled plants in developing countries, this paper presents results for tests carried out on 14 combustion units obtained during field trials in Sri Lanka. The plants tested comprised steam boilers and process air heaters. Biomass fuels included: rubber-wood, fuelwood from natural forests; coconut shells; rice husks; and sugar cane bagasse. Average NOx (NO and NO2) emissions for the plants were found to be 47 gNO2 GJ−1 with 18% conversion of fuel nitrogen. The former value is the range of NOx emission values quoted for combustion of coal in grate-fired systems; some oil-fired systems and systems operating on natural gas, but is less than the emission levels for the combustion of pulverized fuel and heavy fuel oil. This value is significantly within current European standards for NOx emission from large combustion plants. Average thermal efficiency of the plants was found to be 50%. Observations made on operational practices demonstrated that there is considerable scope for the improvement of this thermal efficiency value by plant supervisor training, drying of fuelwood and the use of simple instruments for monitoring plant performance.  相似文献   

19.
The presented study provides details on Fuzzy Logic based control of HHO generators aims at protecting the HHO generator from extreme temperature effects while maximizing the hydrogen production. The Fuzzy Logic Controller mainly focuses on protecting the generator from the harsh effects of process related over heating problems while maximizing the hydrogen production. The designed controller takes two process specific parameters, such as temperature and the HHO flow rate, and optimizes the operation of the reactor for maximization of production. In order to prove the effectiveness of the developed Fuzzy Logic based control approach, a comparative study on performance of conventional and presented novel Fuzzy Logic based systems are presented. The advantage of the Fuzzy Logic Controller is that it protests the reactor and allows continuous production of HHO gas while the conventional approach leads to damage to the reactor or interrupted operation due to overheating.  相似文献   

20.
With a specific end goal to take care of the worldwide demand for energy, a broad research is done to create alternative and cost effective fuel. The fundamental goal of this examination is to investigate the combustion, performance and emission characteristics of diesel engine using biodiesel blends enriched with HHO gas. The biodiesel blends are gotten by blending KOME obtained from transesterification of karanja oil in various proportions with neat diesel. The HHO gas is produced by the electrolysis of water in the presence of sodium bicarbonate electrolyte. The constant flow of HHO gas accompanied with biodiesel guarantees lessened brake specific fuel consumption by 2.41% at no load and 17.53% at full load with increased the brake thermal efficiency by 2.61% at no load and 21.67% at full load contrasted with neat diesel operation. Noteworthy decline in unburned hydrocarbon, carbon monoxide, carbon-dioxide emissions and particulate matter with the exception of NOx discharge is encountered. The addition of EGR controls this hike in NOx with a slight decline in the performance characteristics. It is clear that the addition of HHO gas with biodiesel blends along with EGR in the test engine improved the overall characterization of engine.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号