29 results on '"Peter, Otchere"'
Search Results
2. Experimental Investigation on the Effect of Blending Ethanol on Combustion Characteristic and Idle Performance in a Gasoline Rotary Engine
- Author
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Yangxian Liu, Jianfeng Pan, Biao Cheng, Peter Otchere, Baowei Fan, and Tao Jiayu
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Idle ,business.product_category ,Materials science ,Electric vehicle ,Heat of combustion ,Combustion chamber ,Gasoline ,Condensed Matter Physics ,Combustion ,Pulp and paper industry ,business ,Rotary engine ,NOx - Abstract
Rotary engine is an ideal electric vehicle range extender. However, the combustion chamber of rotary engine is very narrow and long at the top dead center, which is detrimental to fuel combustion performance. In order to improve its economic and emission performance, this paper built an ethanol/gasoline dual-fuel rotary engine test bench, and the combustion and emission performance of gasoline rotary engine under five ethanol blending ratios were studied. The experimental results showed that, when the fuel pulse width is not adjusted, since the calorific value of ethanol is lower than that of gasoline and the latent heat of vaporization of ethanol is higher than that of gasoline, the addition of ethanol in gasoline lowers the peak pressure. When the ethanol blending ratio reaches 30 vol%, the pressure curve shows a distinct double peak. Under the theoretical air-fuel ratio condition, mixing ethanol in gasoline increases the heat release rate, shortens the combustion duration while prolonging delay period. After blending ethanol, HC, CO and NOx emissions have been reduced under various operating conditions. Excessive ethanol blending ratio increases NOx emissions and increases cycle variation coefficient. When the ethanol blending ratio is 15 vol%, it has better power ability while maintaining low cycle variation coefficient and emissions.
- Published
- 2021
3. Design and Construction of an Automatic Sensor Probe for Soil Moisture Monitoring System
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Wisdom Opare and Peter Otchere
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Environmental science ,Monitoring system ,General Medicine ,Water content ,Remote sensing - Published
- 2020
4. Effect of hydrogen addition on the detonation performances of methane/oxygen at different equivalence ratios
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Chao Jiang, Peter Otchere, Zhenhua Pan, Jianfeng Pan, Jianxing Li, and Jing Ni
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Materials science ,Hydrogen ,Renewable Energy, Sustainability and the Environment ,Analytical chemistry ,Detonation ,Energy Engineering and Power Technology ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,Oxygen ,Pressure sensor ,Methane ,0104 chemical sciences ,Ion ,chemistry.chemical_compound ,Fuel Technology ,chemistry ,Inner diameter ,0210 nano-technology ,Flame front - Abstract
Detonation performances of methane/hydrogen/oxygen (CH4/H2/O2) mixtures were investigated experimentally in a 3000 mm long tube with an inner diameter of 30 mm at different initial pressures p 0 (ranging from 10 kPa to 50.5 kPa). Mixtures with different proportions of H2 in the total fuel α (0%, 14.29% and 25%) and different equivalence ratios Φ (0.8, 1.0 and 1.2) were tested. Signals of flame front and pressure were obtained by ion probes and high frequency pressure transducers, respectively. Results showed that with the increase of p 0 , α and Φ , the average velocity of steady detonation V a v e increased. For mixtures with the given α , when Φ increased by 0.2, V a v e increased by 100 m/s. In the present study, velocity deficits were found to be within 5%, and when p 0 was higher than 20 kPa, the velocity deficits were within 2%. The average peak pressure of steady detonation p a v e was close to the von Neumann pressure p v N . Both the increase of p 0 and Φ led to the increase of the p a v e . But the addition of H2 led to the decrease of p a v e , and p a v e decreased with the increased of α .
- Published
- 2019
5. Research on the application of aviation kerosene in a direct injection rotary engine-Part 1: Fundamental spray characteristics and optimized injection strategies
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Peter Otchere, Jianfeng Pan, Chen Wei, Lu Yao, Baowei Fan, and Biao Cheng
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Spray characteristics ,Materials science ,Renewable Energy, Sustainability and the Environment ,020209 energy ,Nuclear engineering ,Energy Engineering and Power Technology ,02 engineering and technology ,Fuel injection ,Rotary engine ,law.invention ,Cylinder (engine) ,Ignition system ,Fuel Technology ,020401 chemical engineering ,Nuclear Energy and Engineering ,Volume (thermodynamics) ,law ,0202 electrical engineering, electronic engineering, information engineering ,0204 chemical engineering ,Combustion chamber ,Spark plug - Abstract
In view of the gradual promotion of Single Fuel Concept in the military field and also the rotary engine (RE) which has been widely applied in specialized equipment, it is necessary to study the basic spray characteristics of aviation kerosene under RE operation conditions and optimize the fuel injection strategies. In this research, an optically visible constant volume combustion chamber platform for Mie-scattering and a validated three-dimensional dynamic simulation model of aviation kerosene fueled direct injection rotary engine (DI-RE) were established. The experimental results show that the ambient temperature and pressure affect the spray process differently. There is no linear relationship between ambient temperature and penetration length. The ambient temperature of 600 K is a watershed, when it is below 600 K, the penetration length increases as the temperature rises. When the temperature reaches 600 K, the penetration length decreases rapidly which means a prominent improvement of atomization quality. On the basis of experimental results, the simulation was carried out and the results show that different injection strategies have important effect on distribution of fuel in cylinder, the larger injection angle will promote the atomization of fuel due to the collision between the spray and air flow field. In Case A3, B2 and C2, the fuel mainly distributes near the spark plugs in the center of the combustion chamber, which is supposed to be more conducive to the ignition and diffusion combustion process of the fuel.
- Published
- 2019
6. Numerical investigation of direct injection stratified charge combustion in a natural gas-diesel rotary engine
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Chen Wei, Yangxian Liu, Hongjun Liu, Jianfeng Pan, Baowei Fan, and Peter Otchere
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Materials science ,business.industry ,020209 energy ,Mechanical Engineering ,Nuclear engineering ,Airflow ,02 engineering and technology ,Building and Construction ,Management, Monitoring, Policy and Law ,medicine.disease_cause ,Combustion ,Rotary engine ,Soot ,Diesel fuel ,General Energy ,020401 chemical engineering ,Natural gas ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Ignition timing ,0204 chemical engineering ,Combustion chamber ,business - Abstract
To further improve the performance of diesel rotary engine, a novel natural gas-diesel rotary engine was proposed and studied in this paper. Based on a spray experimental setup, the diesel spray characteristics under diesel rotary engine working conditions were obtained and analyzed. Thereafter it was used to validate the spray model for diesel rotary engine modeling and simulation. The effect of different natural gas blending ratios on mixture formation and combustion process in the natural gas-diesel rotary engine were investigated. Simulation results showed that for fuel-air mixing process, the natural gas movement process was susceptible to the airflow motion. However, the diesel distribution range was obviously enlarged under the influence of high-speed unidirectional flow. At assisted ignition timing, the stratified distributed diesel made the combustion process mainly occured at the front and middle of the combustion chamber. Besides, the flame propagation speed was accelerated with natural gas blending ratio increasing, which effectively improved the total combustion rate. Compared to single-fuel mode, when natural gas blending ratio increased to 20%, the maximum combustion pressure increased by 24.17%. Meanwhile, soot and CO decreased obviously, but NO and CO2 also increased.
- Published
- 2019
7. Numerical investigation of dual-fuel injection timing on air-fuel mixing and combustion process in a novel natural gas-diesel rotary engine
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Jianfeng Pan, Chen Wei, Baowei Fan, Peter Otchere, Lu Yao, and Nannan Miao
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Engine power ,Materials science ,Renewable Energy, Sustainability and the Environment ,020209 energy ,Nuclear engineering ,Energy Engineering and Power Technology ,02 engineering and technology ,medicine.disease_cause ,Combustion ,Fuel injection ,Rotary engine ,Soot ,Diesel fuel ,Fuel Technology ,020401 chemical engineering ,Nuclear Energy and Engineering ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Ignition timing ,0204 chemical engineering ,Combustion chamber - Abstract
This study aimed at further improving the combustion efficiency of the diesel rotary engine (DRE), and in this regard a novel natural gas-diesel rotary engine (NG-DRE) was numerically studied. Based on the experimental validated computational fluid dynamics (CFD) model, a 3D-dynamic numerical study of the NG-DRE was carried out by adopting NG port injection plus diesel direct injection mode. The influence of natural gas injection timing (NGIT) and diesel injection timing (DIT) on air-fuel mixing, combustion and emission characteristics were explored. Simulation results showed that NG-DRE performance was better than DRE. During the entire air-fuel mixing process, NG movement was easily affected by the vorticity density due to its good diffusion characteristics, however its influence on diesel movement was relatively minimal. At assisted ignition timing, NG concentrated at the rear of the combustion chamber, and diesel concentrated at the front and middle of the combustion chamber. Delaying NGIT and DIT, the mixture became more concentrated due to a shorter mixing time. Moreover, the delayed NGIT and DIT resulted in improvement of the pressure and combustion rate, while for a further delayed DIT the pressure was decreased due to the pressure negative work. Considering the engine power and emission performance, for dual-fuel injection schemes, 340°CA BTDC and 70°CA BTDC were the preferred application schemes for NG and diesel respectively. Their peak combustion pressure (Pmax) increased by 16.34% and 27.38% respectively, but due to the richer mixture, soot value increased by 0.023% and 0.054% and CO (carbon monoxide) value also increased by 0.026% and 0.039% respectively.
- Published
- 2018
8. The influence of hydrogen injection strategy on mixture formation and combustion process in a port injection (PI) rotary engine fueled with natural gas/hydrogen blends
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Chen Wei, Yangxian Liu, Jianfeng Pan, Wei Aibo, Peter Otchere, Baowei Fan, Zhang Yaoyuan, and Ren He
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Materials science ,Hydrogen ,020209 energy ,Analytical chemistry ,Energy Engineering and Power Technology ,chemistry.chemical_element ,02 engineering and technology ,Combustion ,law.invention ,Natural gas ,law ,0502 economics and business ,0202 electrical engineering, electronic engineering, information engineering ,Hydrogen fuel enhancement ,050207 economics ,Spark plug ,Heat engine ,Renewable Energy, Sustainability and the Environment ,business.industry ,05 social sciences ,Fuel Technology ,Nuclear Energy and Engineering ,chemistry ,Ignition timing ,Combustion chamber ,business - Abstract
This work aimed to numerically study the effect of hydrogen injection strategy on mixture formation and combustion process in a port injection (PI) rotary engine fueled with natural gas/hydrogen blends. The two main considered factors were hydrogen injection timing (IT) and hydrogen injection duration (ID). Simulation results indicated that for mixture formation, in terms of hydrogen IT, hydrogen IT of 390°CA (BTDC) is a watershed. When the hydrogen IT is before 390°CA (BTDC), the changes in hydrogen IT have little effect on the hydrogen distribution at ignition timing. Hydrogen distribution is uniform across the whole combustion chamber. However, when the hydrogen IT is after 390°CA (BTDC), with the retarded hydrogen IT, there is obvious increase in hydrogen stratification phenomenon, and more hydrogen distributes in the middle and back of combustion chamber at ignition timing. In terms of hydrogen ID, at the fixed hydrogen IT of 360°CA (BTDC), with the extended hydrogen ID, more hydrogen distributes in the back of trailing spark plug (TSP). For combustion process, to obtain a higher overall combustion rate for the PI rotary engine, the hydrogen injection strategy should make more hydrogen located at the front of TSP at ignition timing. In engineering applications, for higher peak cylinder pressure to be obtained, the continued optimization of hydrogen IT should be selected between 390°CA (BTDC) and 330°CA (BTDC). Under the hydrogen IT range of 390°CA (BTDC) to 330°CA (BTDC), the continued optimization of hydrogen ID should select between 8°CA and 24°CA.
- Published
- 2018
9. Biodiesel Spray Characteristics and a CFD Simulation Study of Injection Timing Effects on the Combustion Process in a Biodiesel-Fueled, Direct-Injection Rotary Engine
- Author
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Lu Yao, Jianfeng Pan, Li Jianxing, Chen Wei, Peter Otchere, and Baowei Fan
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Spray characteristics ,020301 aerospace & aeronautics ,Cfd simulation ,Biodiesel ,Renewable Energy, Sustainability and the Environment ,business.industry ,Mixture formation ,Fossil fuel ,Energy Engineering and Power Technology ,02 engineering and technology ,Alternative fuels ,01 natural sciences ,Rotary engine ,010305 fluids & plasmas ,0203 mechanical engineering ,Nuclear Energy and Engineering ,Combustion process ,0103 physical sciences ,Environmental science ,business ,Process engineering ,Waste Management and Disposal ,Civil and Structural Engineering - Abstract
Energy conservation is important in this modern era because of its high demand in transportation systems coupled with the depletion of fossil fuels. Biodiesel is thus an alternative fuel to...
- Published
- 2020
10. Recent Studies of Fuels Used in Wankel Rotary Engines
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Peter Otchere, Lu Yao, Jianfeng Pan, Baowei Fan, and Chen Wei
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Renewable Energy, Sustainability and the Environment ,business.industry ,020209 energy ,Mechanical Engineering ,Wankel engine ,05 social sciences ,Energy Engineering and Power Technology ,02 engineering and technology ,Combustion ,Rotary engine ,Fuel Technology ,Geochemistry and Petrology ,Biofuel ,0502 economics and business ,0202 electrical engineering, electronic engineering, information engineering ,Environmental science ,050207 economics ,Process engineering ,business - Abstract
During the decades past, the engine industries have witnessed a remarkable upsurge in the research and development (R&D) of modern technologies due to factors such as energy security and environmental concerns. Focus is on improved engine performance, sustainable energy, fuel economy, and minimal harmful exhaust emissions. Even though globally large database now captures modern engine technologies, a skillful presentation of those data is a demanding task. Based on this analogy, the authors made a conscious effort to brief audience on the various fuels used in Wankel rotary engine (RE) which is a type of internal combustion engine (ICE). Wankel REs various operating models, their merits, and demerits regarding modern engine technologies, the type of fuels and their utilization methods, and the future prospect of biofuel as its engine fuel has been made accessible in a subtle manner in this paper. In summary, this paper provides a wide scope review of basic principles that govern practical Wankel RE design and operation, the widely used single fuels and multi fuels in Wankel RE operation with their properties as well as emissions, and the practical Wankel RE design and operation in the present era and the prospects in the near future. It also outlines simplified frameworks of modern Wankel RE technologies structured in a systematic way to contribute to enhanced engine performance, sustainable energy, reduce fuel consumption, and reduce exhaust emissions in this pragmatic field.
- Published
- 2020
11. Experimental and Numerical Study on the Formation Mechanism of Flow Field in a Side-Ported Rotary Engine Considering Apex Seal Leakage
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Peter Otchere, Baowei Fan, Jianfeng Pan, Zhang Yaoyuan, and Wang Yuanguang
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0303 health sciences ,Materials science ,Renewable Energy, Sustainability and the Environment ,Mechanical Engineering ,05 social sciences ,Energy Engineering and Power Technology ,Mechanics ,Rotary engine ,Flow field ,03 medical and health sciences ,Fuel Technology ,Geochemistry and Petrology ,0502 economics and business ,050207 economics ,030304 developmental biology ,Leakage (electronics) - Abstract
The aim of this research is to investigate the influences of apex seal leakage on the formation mechanism of flow field in a side-ported rotary engine by particle image velocimetry (PIV) and computational fluid dynamics (CFD). In this study, a PIV was used to acquire the two-dimensional (2D) flow field on the rotor housing central plane at an engine speed of 700 rpm. A three-dimensional (3D) dynamic simulation model considering leakage through apex seals was established and verified by the 2D-PIV experiment results. Thereafter, CFD analysis was used to further understand the 3D flow field in combustion chamber under the action of apex seal leakage. The simulation results showed that for the three engine speeds (2000, 3500, and 5000 rpm), in the intake stroke, the vortex generated in the front end of combustion chamber under the condition with no leakage, was strengthened and destroyed by the effects of the small (0.02 mm) and the large (0.08 mm) apex seal leakage gaps, respectively. As the apex seal leakage gap increased, the volume efficiency and the peak pressure decreased continuously. The volume efficiency and the peak pressure caused by any fixed apex seal leakage gap decreased with the increase of the engine speed. Compared with the volumetric efficiency of the condition with no leakage at 2000 and 5000 rpm, the volumetric efficiency of apex seal leakage gap of 0.08 mm decreased only by 24.6% at 5000 rpm, but by 41.2% at 2000 rpm.
- Published
- 2020
12. The formation mechanisms of flow field in a compound intake ported rotary engine considering apex seal leakage
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Jianfeng Pan, Yonghao Zeng, Baowei Fan, Zhang Yaoyuan, Peter Otchere, and Wang Yuanguang
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Environmental Engineering ,Materials science ,Renewable Energy, Sustainability and the Environment ,General Chemical Engineering ,Environmental Chemistry ,Mechanics ,Waste Management and Disposal ,Flow field ,Rotary engine ,General Environmental Science ,Water Science and Technology ,Leakage (electronics) - Published
- 2020
13. Numerical investigation of mixture formation and combustion in a hydrogen direct injection plus natural gas port injection (HDI + NGPI) rotary engine
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Baowei Fan, Yangxian Liu, Jianfeng Pan, Peter Otchere, Lu Yao, and Chen Wei
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Materials science ,Hydrogen ,020209 energy ,Analytical chemistry ,Energy Engineering and Power Technology ,chemistry.chemical_element ,02 engineering and technology ,Combustion ,Rotary engine ,law.invention ,Natural gas ,law ,0502 economics and business ,0202 electrical engineering, electronic engineering, information engineering ,Hydrogen fuel enhancement ,050207 economics ,Spark plug ,Renewable Energy, Sustainability and the Environment ,business.industry ,05 social sciences ,Condensed Matter Physics ,Fuel Technology ,chemistry ,Ignition timing ,Combustion chamber ,business - Abstract
Hydrogen direct injection (HDI) in cylinder is considered as an effective method to improve natural gas engine performance. The present study aims to bridge the gap on the HDI in rotary engine, and to investigate the effect of hydrogen injection timing (IT) and hydrogen injection duration (ID) on mixture formation and combustion process of a hydrogen direct injection plus natural gas port injection (HDI + NGPI) rotary engine. Numerical approach was used in this study for obtaining some critical information, which was difficult to obtain through experiment, such as flow field, fuel distribution and some intermediate concentration fields in cylinder. The research results showed that for mixture formation, the distribution law of the hydrogen and the natural gas at the late stages of the compression stroke (100°CA (BTDC)), was as follows: at a fixed ID of 24°CA, with retarded hydrogen IT, the stratification phenomenon of hydrogen became obvious increasingly, and the hydrogen distribution area moved towards the back of the combustion chamber continuously. At a fixed IT of 210°CA (BTDC), with the extension in ID, the accumulation area of hydrogen reduced significantly, and the hydrogen continued to gather in the middle of the combustion chamber. For combustion process, the overall combustion rate for the hydrogen injection strategy which had an IT of 210°CA (BTDC) and ID of 40°CA (case ID5), was the fastest. This was due to the fact that compared with the leading spark plug (LSP), the combustion condition around the trailing spark plug (TSP) has a great influence on the combustion process. For case ID5 at ignition timing, the hydrogen concentration near the TSP is high enough for the rapid formation of flame kernel. Compared with case IT1 which had an IT of 390°CA (BTDC) and an ID of 24°CA, the improved combustion rate of case ID5 had a 11.7% increase in peak pressure, and a 7% decrease in NO emissions.
- Published
- 2018
14. Effect of hydrogen injection strategies on mixture formation and combustion process in a hydrogen direct injection plus natural gas port injection rotary engine
- Author
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Yangxian Liu, Jianfeng Pan, Baowei Fan, Zhenhua Pan, Peter Otchere, Chen Wei, and Yuejin Zhu
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Materials science ,Hydrogen ,Renewable Energy, Sustainability and the Environment ,business.industry ,020209 energy ,Nuclear engineering ,Energy Engineering and Power Technology ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Combustion ,law.invention ,Fuel Technology ,Nuclear Energy and Engineering ,chemistry ,law ,Natural gas ,0202 electrical engineering, electronic engineering, information engineering ,Hydrogen fuel enhancement ,Stroke (engine) ,Ignition timing ,Combustion chamber ,0210 nano-technology ,Spark plug ,business - Abstract
This work aimed to numerically study the effect of hydrogen injection strategies on mixture formation and combustion process in a hydrogen direct injection plus natural gas port injection (HDI + NGPI) rotary engine. Two major factors, namely hydrogen injection timing (HIT) and hydrogen injection angle (HIA), were considered. Four HITs which were used in simulation, were from the early stages of intake stroke to the late stages of compression stoke. Comparing the fuel movement and combustion process among the four HITs with three HIAs (−60°, 0° and 60°), it was found that for hydrogen movement, when the HIT was at early stages of intake stroke, this advanced HIT led to the fact that the hydrogen distribution areas at ignition timing all spread across the whole combustion chamber for all three HIA cases. When the HIT was at the late stages of the intake stroke and the whole compression stroke, with an increased hydrogen injection angle (HIA) (from −60°, 0° to 60°), the hydrogen accumulation area moved from the front towards the rear of combustion chamber. In addition, with retarded HIT, the hydrogen aggregation degree increased continuously. For combustion process, to obtain a higher overall combustion rate, the hydrogen injection strategy should make as much hydrogen spread between the two spark plugs at ignition timing. In addition, the hydrogen concentration near the LSP and the TSP should be conducive to the flame kernel formation. This is mainly because of the fact that the above hydrogen distributions, not only lead to the rapid formation of the flame kernel near the LSP and the TSP, but also make use of the hydrogen at the early stage of combustion stroke. Under the computational condition, the overall combustion rate for case A: 140 − 60 which had a HIT of 140°CA (BTDC) and a HIA of −60°CA, was the fastest. Compared with case C: 300 + 60 which had a HIT of 300°CA (BTDC) and a HIA of 60°CA, the peak pressure of case A: 140 − 60 was raised by 31.1%. However, compared with other cases, the NO emissions of case A: 140 − 60 at 80°CA (ATDC) was the maximum. Furthermore, for engineering applications, this study also provided a scheme of the change of the optimum HIA under different HITs for improving the performance of the HDI + NGPI rotary engine.
- Published
- 2018
15. Stratified combustion characteristics analysis and assisted-ignition strategy optimization in a natural gas blended diesel Wankel engine
- Author
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Lu Yao, Wenming Yang, Chen Wei, Baowei Fan, Yangxian Liu, Jianfeng Pan, and Peter Otchere
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business.industry ,020209 energy ,General Chemical Engineering ,Wankel engine ,Organic Chemistry ,Stratified combustion ,Energy Engineering and Power Technology ,02 engineering and technology ,Combustion ,Automotive engineering ,law.invention ,Ignition system ,Diesel fuel ,Fuel Technology ,020401 chemical engineering ,law ,Natural gas ,0202 electrical engineering, electronic engineering, information engineering ,Environmental science ,Ignition timing ,0204 chemical engineering ,Spark plug ,business - Abstract
It is important to improve the combustion performance of the diesel Wankel engine for its further engineering applications. Therefore, the main objective of this study was to study the dual-fuel mixture formation and stratified combustion process in the novel natural gas blended diesel Wankel engine. Meanwhile, the effects of assisted-ignition timing and assisted-ignition position on engine combustion characteristics were investigated. The results indicated that when the assisted-ignition timings and positions were changed, natural gas distribution near assisted-spark plugs changed slightly, while the variation of diesel distribution was conspicuous. Moreover, adopting dual assisted-ignition spark plugs could accelerate the fuel burning rate and improve engine combustion performance. Besides, it was found that more mixture concentrated near the assisted-spark plugs was beneficial to increase the pressure in-cylinder and combustion rate. The symmetrical arranged dual assisted-ignition spark plugs that were respected to the X-axis (Case 4) and assisted-ignition timing of 35°CA BTDC (Case 6) were the preferred practical application schemes. Compared to the schemes of single spark plug ignition (Case 1) and 20°CA BTDC ignition timing (Case 9), the peak pressure in-cylinder of the preferred application schemes increased by 42.96% and 10.91%, respectively.
- Published
- 2021
16. Effect of gas-phase reaction on catalytic reaction for H2/O2 mixture in micro combustor
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Yangxian Liu, Jianfeng Pan, Aikun Tang, Peter Otchere, Yi Zhang, Zhenhua Pan, and Qingbo Lu
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Order of reaction ,060102 archaeology ,Renewable Energy, Sustainability and the Environment ,Chemistry ,05 social sciences ,Energy Engineering and Power Technology ,06 humanities and the arts ,Condensed Matter Physics ,Photochemistry ,Chemical reaction ,Catalysis ,Chemical kinetics ,Dry media reaction ,Reaction rate ,Fuel Technology ,Reaction rate constant ,Catalytic cycle ,0502 economics and business ,0601 history and archaeology ,050207 economics - Abstract
The catalytic reaction characteristics of the hydrogen and oxygen mixture in the catalytic micro-combustor were detected by thermocouple, infrared thermal imager and OH-PLIF. The equivalence ratio of transition stage from coupling reaction (coupled homogeneous-heterogeneous combustion) to pure catalytic reaction (heterogeneous combustion) was obtained. The three-dimensional pure catalytic reaction model with detailed catalytic reaction mechanism was established in a rectangular catalytic micro-combustor. The simulation model was validated with experimental data. The effects of the intermediate and final products from gas-phase reactions on the pure catalytic reaction were discussed as well as the effects of gas-phase reactions on the catalytic reaction in the process of coupling reactions were studied. The intermediate product OH radical can improve the hydrogen conversion of the surface reaction, and the effect of O radical is not obvious. The final product H2O has an inhibitory effect on the surface reaction. Since the mass fraction of H2O is much higher than other gas-phase reaction products, the dominant effect of the gas-phase reaction on the catalytic reaction is suppression. In the coupling reactions, the fuel consumed by the gas-phase reaction weakened the catalytic reaction.
- Published
- 2017
17. Mixture formation and combustion process of a biodiesel fueled direct injection rotary engine (DIRE) considering injection timing, spark timing and equivalence ratio – CFD study
- Author
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Jianfeng Pan, Peter Otchere, Chen Wei, Li Jianxing, Baowei Fan, and Lu Yao
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Biodiesel ,Renewable Energy, Sustainability and the Environment ,business.industry ,020209 energy ,Nuclear engineering ,Mixture formation ,Energy Engineering and Power Technology ,Environmental pollution ,02 engineering and technology ,Computational fluid dynamics ,Combustion ,medicine.disease_cause ,Rotary engine ,Soot ,Fuel Technology ,020401 chemical engineering ,Nuclear Energy and Engineering ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Environmental science ,0204 chemical engineering ,Combustion chamber ,business - Abstract
Rotary engine has a flat combustion chamber that results in high unburned fuel leading to fuel inefficiency and emissions. Biodiesel regarded as a clean source of energy is an alternative fuel due to its ability to minimize environmental pollution resulting from unwanted emissions. In this regard, the improvement of combustion efficiency of a direct injection rotary engine fueled with biodiesel was numerically investigated. Experimental data was used in validating the established three-dimensional computational fluid dynamics (3D-CFD) model. On this basis, investigation of various biodiesel injection timing (IT) (100, 80, 60) °CA before top dead center (BTDC), spark timing (ST) (35, 30, 25, 20) °CA BTDC and equivalence ratios ( ∅ ) (0.6, 0.8, 1.0, 1.2) on mixture formation and combustion process was carried out. Results revealed that when IT retarded fuel distribution narrows and the mixture formed is concentrated. Conversely when ST retarded there is broad and dispersed fuel distribution. For lean condition the mixture formed is less concentrated compared to rich condition. For combustion process, when biodiesel was concentrated at the middle of in-cylinder at 30 mm (X-axis) and 15 mm (Z-axis) from the centerline in opposing directions it was better for spark-on. Also, the in-cylinder pressure and temperature reduced with advanced IT, retarded ST and decreased ∅ . When ∅ leaned, flame development and propagation periods decreased. The suitable rate for combustion considering emissions was obtained when IT was 80°CA (BTDC) and ST 35°CA (BTDC) at a ∅ of 0.8 because when compared to the original scheme (case B4), maximum combustion pressure increased by 28.57% and increase of CO2, CO, soot and NO emissions were reasonable due to increase in temperature and fuel evaporation.
- Published
- 2020
18. Research on the application of aviation kerosene in a direct injection rotary engine – Part 2: Spray combustion characteristics and combustion process under optimized injection strategies
- Author
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Jianfeng Pan, Baowei Fan, Chen Wei, Biao Cheng, Lu Yao, and Peter Otchere
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Renewable Energy, Sustainability and the Environment ,020209 energy ,Energy Engineering and Power Technology ,02 engineering and technology ,Combustion ,medicine.disease_cause ,Rotary engine ,Automotive engineering ,Soot ,Cylinder (engine) ,law.invention ,Ignition system ,Fuel Technology ,020401 chemical engineering ,Nuclear Energy and Engineering ,law ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Environmental science ,Ignition timing ,0204 chemical engineering ,Combustion chamber ,Ambient pressure - Abstract
Investigating the adaptability of aviation kerosene in the direct injection rotary engine is of great significance and practical value. In this paper, an optically visible constant volume combustion chamber platform with various optical diagnostic techniques was firstly set up to study the spray combustion characteristics of the fuel. Secondly, a reliable three-dimensional dynamic simulation model of direct injection rotary engine was established to investigate the combustion process of aviation kerosene under optimized injection strategies. The experimental results show that the ambient temperature of 800 K and ambient pressure of 20 bar is the ignition limit of aviation kerosene under the condition of rotary engine. With the increase of ambient conditions, the ignition delay and the flame lift-off length shorten continuously. At 850 K ambient temperature, when the ambient pressure reaches 25 bar, the lift-off length will no longer shorten and remains at about 6 mm. The simulation results indicate that under the Injection position A-Injection angle 90° (Case A3), higher combustion efficiency before top dead center can be achieved due to more appropriate distribution, concentration and atomization quality of fuel at ignition timing. The peak pressure in cylinder reaches 38.89 bar, which means a better engine dynamic performance. Meanwhile, acceptable CO and Soot emissions are obtained by the complete combustion of fuel in Case A3, however, the higher combustion temperature makes the production of pollutant NO slightly higher than other injection strategies.
- Published
- 2020
19. Effect of different hydrogen blending ratios on combustion process of gasoline‐fueled rotary engine
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Jianfeng Pan, Baowei Fan, Peter Otchere, Lu Yao, Chen Wei, and Mingcai Huang
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Environmental Engineering ,Materials science ,Hydrogen ,Renewable Energy, Sustainability and the Environment ,business.industry ,General Chemical Engineering ,chemistry.chemical_element ,Rotary engine ,chemistry ,Combustion process ,Environmental Chemistry ,Gasoline ,Process engineering ,business ,Waste Management and Disposal ,General Environmental Science ,Water Science and Technology - Published
- 2019
20. Reviewers.
- Subjects
RENEWABLE energy sources ,ACQUISITION of manuscripts - Published
- 2021
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21. The formation mechanisms of flow field in a compound intake ported rotary engine considering apex seal leakage.
- Author
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Fan, Baowei, Zhang, Yaoyuan, Pan, Jianfeng, Otchere, Peter, Wang, Yuanguang, and Zeng, Yonghao
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ROTARY combustion engines ,PARTICLE image velocimetry ,COMBUSTION efficiency ,HEAT of combustion ,COMBUSTION chambers ,LEAKAGE ,HARBORS - Abstract
The development of rotary engines is severely restricted by its low combustion efficiency and high emission. In‐cylinder flow field is known to play a major role in combustion process for rotary engines. Therefore, in the present article, a three‐dimensional dynamic simulation model considering leakage through apex seals was developed and verified by the two‐dimensional particle image velocimetry experiment results on the rotor housing central plane. Based on the three‐dimensional dynamic simulation model, the formation mechanisms of flow field in a compound intake ported rotary engine under different apex seal leakage gap sizes (0.02, 0.04, 0.06, and 0.08 mms) and engine speeds (2,000, 3,500, and 5,000 rpms) were numerically studied. The simulation results showed that there exist two formation mechanisms of the flow field in the intake stroke, that is, "side intake port dominance" and "peripheral intake port dominance." For the three engine speeds (2,000, 3,500, and 5,000 rpms), with the increase of apex seal leakage gap size, the formation mechanism of the flow field gradually changed from "side intake port dominance" to "peripheral intake port dominance." In addition, the influences of apex seal leakage on the volume coefficient and the turbulence kinetic energy in the combustion chamber were also investigated in detail. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
22. Biodiesel Spray Characteristics and a CFD Simulation Study of Injection Timing Effects on the Combustion Process in a Biodiesel-Fueled, Direct-Injection Rotary Engine.
- Author
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Otchere, Peter, Pan, Jianfeng, Fan, Baowei, Chen, Wei, Lu, Yao, and Jianxing, Li
- Subjects
ROTARY combustion engines ,BIODIESEL fuels ,COMPUTATIONAL fluid dynamics ,COMBUSTION ,ENERGY conservation ,FOSSIL fuels - Abstract
Energy conservation is important in this modern era because of its high demand in transportation systems coupled with the depletion of fossil fuels. Biodiesel is thus an alternative fuel to replace conventional diesel. This study investigates the effect of chamber pressure (Pamb) and chamber temperature (Tamb) on biodiesel spray penetration length (SL) and spray pattern (SP) characteristics in a constant-volume vessel, under rotary engine working conditions, using spray visualization and image processing techniques. Furthermore, a three-dimensional (3D) direct-injection rotary engine model was developed and used for computational fluid dynamics (CFD) simulation studies of biodiesel distribution, mixture forming, and combustion process at different injection timing (IT) in the cylinder. Results indicate that increasing Pamb decreases SL and broadens SP , while increasing Tamb decreases SL and narrows SP. At advanced IT, biodiesel diffuses and disperses, and at retarded IT, which is the suitable rate for combustion, biodiesel concentrates and narrows. Compared with the original scheme [80° crank angle before top dead center (CA BTDC)], Pmax increases by 16.79%, ϕmax decreases by 28.75%, NO and CO change a little, and CO2 decreases. Its drawback is a 15.65% increase in soot formation. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
23. Numerical investigation of the effect of advance ignition timing on combustion process in direct injection rotary engine fueled with biodiesel.
- Author
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Otchere, Peter, Pan, Jianfeng, Fan, Baowei, Chen, Wei, Yao, Lu, and Jianxing, Li
- Subjects
BIODIESEL fuels ,ROTARY combustion engines ,COMBUSTION ,CLEAN energy ,CHEMICAL kinetics ,FOSSIL fuels - Abstract
Biodiesel is a clean energy source that helps in the reduction of environmental pollution as compared to fossil fuel. This study aimed to improve the performance of combustion and reduce emission in direct injection rotary engine by fueling it with biodiesel as well as selecting the best ignition time. A 3D‐dynamic simulation model was established and then coupled with biodiesel chemical kinetics mechanism. On this basis, investigation of five ignition timings (IT) was conducted to know their various effects on combustion process. The simulation results showed that properly advancing IT increased in‐cylinder pressure, with the peak pressure (Pmax) of 35°CA (BTDC) IT of 45.99 bar the largest. Comparing IT of 35°CA (BTDC) with the IT of the original engine showed an 18.14% increase in peak pressure. The corresponding crank angle (φmax) for Pmax values also proved that when the IT was advanced, φmax values decreased and that of 35°CA (BTDC)‐10.37°CA (ATDC), 30°CA (BTDC)‐11.46°CA (ATDC), and 25°CA (BTDC)‐13.88°CA (ATDC) were better because they were generally between 10–15°CA (ATDC), which contributes to better engine performance. With advanced IT, phase of total period during combustion was continuously brought forward due to flame propagation acceleration by tumble as well as increase of tumble residence effect time that aided in improving the combustion rate. The burnt fuel mass fractions at TDC of 40°CA (BTDC) IT of 0.94 was the highest followed by 35°CA (BTDC) IT of 0.88. Under this computational condition, 35°CA (BTDC) was deemed to be the improved combustion scheme though soot exhaust increased. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
24. Effect of different hydrogen blending ratios on combustion process of gasoline‐fueled rotary engine.
- Author
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Pan, Jianfeng, Lu, Yao, Huang, Mingcai, Otchere, Peter, Chen, Wei, and Fan, Baowei
- Subjects
ROTARY combustion engines ,COMBUSTION ,COMBUSTION kinetics ,HYDROGEN as fuel ,GASOLINE ,ENERGY consumption ,CHEMICAL engineering - Abstract
The pre‐eminent gasoline rotary engine may be criticized for its unsatisfactory fuel consumption rate and unburnt emissions. The clean and renewable hydrogen fuel is a promising alternative for conventional fuels to improve the combustion process and power performance of the rotary engine. In this article, highly advanced numerical simulation was used to obtain some pivotal results such as the distribution of combustion intermediates, the turbulent kinetic energy, the kinetic rate of reactions, and the fuel concentration fields which are difficult to experimentally achieve. An experimentally validated three‐dimensional dynamic simulation model of a rotary engine coupled with chemical kinetics skeletal mechanism was set up to exactly investigate the effects of hydrogen blending on the combustion process, power performance, and pollutant emissions. The results showed that with the increase of hydrogen mixing ratio, the average pressure and the peak pressure increased in the combustion process. Meanwhile, more combustion active intermediates were generated in both the flame development period and flame propagation period. The mass fraction of OH and H radicals has an increase of 36% and 34%, respectively. The fuel combustion rate rose and the turbulent kinetic energy increased which are conducive to improving flame diffusion in the rear part of the chamber and thus facilitate the complete combustion of the fuel. Moreover, the hydrogen blending led to an effective reduction in the CO emission of gasoline‐fueled rotary engine; however, the NO emission slightly increased due to the rise of temperature in cylinder. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019 [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
25. Reports on Biofuel from Jiangsu University Provide New Insights (Experimental Investigation On the Effect of Blending Ethanol On Combustion Characteristic and Idle Performance In a Gasoline Rotary Engine)
- Subjects
Alcohol ,Biomass energy ,Internal combustion engines ,Alcohol, Denatured ,Combustion ,Acetaldehyde ,Biotechnology industry ,Pharmaceuticals and cosmetics industries - Abstract
2021 JUL 28 (NewsRx) -- By a News Reporter-Staff News Editor at Biotech Week -- Researchers detail new data in Biotechnology - Biofuel. According to news reporting from Jiangsu, People's [...]
- Published
- 2021
26. Data from Jiangsu University Provide New Insights into Sustainable Energy (Recent Studies of Fuels Used In Wankel Rotary Engines)
- Subjects
Internal combustion engine industry ,Green technology ,Biotechnology industry ,Pharmaceuticals and cosmetics industries - Abstract
2021 MAR 24 (NewsRx) -- By a News Reporter-Staff News Editor at Biotech Week -- Investigators publish new report on Sustainability Research - Sustainable Energy. According to news reporting out [...]
- Published
- 2021
27. Tension Brews in Asawase Constituency
- Abstract
Byline: Issah Alhassan Accra, Sep 10, 2007 (Ghanaian Chronicle/All Africa Global Media via COMTEX) -- The New Patriotic Party's quest to wrest the seat of the only "orphan" constituency in […]
- Published
- 2007
28. Asawasi NPP Elects Executives
- Abstract
Kumasi., May 04, 2004 (Ghanaian Chronicle/All Africa Global Media via COMTEX) -- The newly created Asawasi constituency in Kumasi has elected its executives to intensify the electioneering campaign of the […]
- Published
- 2004
29. NDC Claims As Child's Joke Say New Patriotic Party
- Abstract
Sep 17, 2003 (Accra Mail/All Africa Global Media via COMTEX) Mr. Fredrick Fredua Antoh, Ashanti Regional Chairman of the New Patriotic Party (NPP), has dismissed claims by the National Democratic […]
- Published
- 2003
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