To improve the energy utilization efficiency of internal combustion （IC） engine, exergy analysis was conducted on a passenger car gasoline engine. According to the thermodynamic theory of IC engine, in-cylinder exer...To improve the energy utilization efficiency of internal combustion （IC） engine, exergy analysis was conducted on a passenger car gasoline engine. According to the thermodynamic theory of IC engine, in-cylinder exergy balance model was built. The working processes of gasoline engine were simulated by using the GT-power. In this way, the required parameters were calculated and then gasoline engine exergy balance was obtained by programming on computer. On this basis, the influences of various parameters on exergy balance were analyzed. Results show that, the proportions of various forms of exergy in gasoline engine from high to low are irreversible loss, effective work, exhaust gas exergy and heat transfer exergy. Effective exergy proportion fluctuates with cylinder volumetric efficiency at full load, while it always increases with break mean effective pressure （BMEP） at part load. Exhaust gas exergy proportion is more sensitive to speed, and it increases with speed increasing except at the highest speed. The lower proportion of heat transfer exergy appears at high speed and high load. Irreversible loss is mainly influenced by load. At part load, higher BMEP results in lower proportion of irreversible loss; at full load, the proportion of irreversible loss changes little except at the highest speed.展开更多
The chemical detection of gasoline traces in fire debris is a challenge requiring highly sensitive,hyphenated analytical systems.The gas chromatography-mass spectrometry is suitable for the task.In this study,GC-MS we...The chemical detection of gasoline traces in fire debris is a challenge requiring highly sensitive,hyphenated analytical systems.The gas chromatography-mass spectrometry is suitable for the task.In this study,GC-MS were optimized to identify gasoline in simulated fire.And it was successful to apply this method to detect the gasoline in fire debris.展开更多
Gasoline and its residues were examined by GC-MS technology.The method can be used to distinguish gasoline and its residues under the nature,combustion and volatility conditions,respectivesy.It can be provide useful i...Gasoline and its residues were examined by GC-MS technology.The method can be used to distinguish gasoline and its residues under the nature,combustion and volatility conditions,respectivesy.It can be provide useful information in criminal cases.展开更多
This coming September will mark the 90th birthday of Academician Wanzhen LU,one of the best scientists in the field of analytical chemistry and petroleum chemistry both in China and around the world.Academician LU was...This coming September will mark the 90th birthday of Academician Wanzhen LU,one of the best scientists in the field of analytical chemistry and petroleum chemistry both in China and around the world.Academician LU was born in Tianjin,Peoples’Republic of China on September 29,1924.Her father is a famous展开更多
Trace gasoline residual analysis and identification is often applied in criminal analysis of arson,explosion,murder e.g..We analysis the trace gasoline in medium with SPME and GC-MS,that can identify the trace gasolin...Trace gasoline residual analysis and identification is often applied in criminal analysis of arson,explosion,murder e.g..We analysis the trace gasoline in medium with SPME and GC-MS,that can identify the trace gasoline residual exactly through analyzing the mass spectrum of chromatogram peaks characters of alkenes,alkyl benzene,indene compounds,and naphthyl compounds,which are from the medium and burning medium.展开更多
The structure of elemental sulfur (S0) in naphtha and gasoline was studied basing on that a new analytical method for determination of S0 was developed using gas chromatography-mass spectrometry (GC-MS).The test showe...The structure of elemental sulfur (S0) in naphtha and gasoline was studied basing on that a new analytical method for determination of S0 was developed using gas chromatography-mass spectrometry (GC-MS).The test showed that the structure of S0 has changed and a small quantity of S2,S6,S7 has resulted and the mass proportion of S2∶S6∶S7∶S8 was 0.13:0.05:0.04:1.00 under the analysis condition.So the change of S0 structure with temperature had no effect on its quantity analysis.展开更多
The nozzle inner-flow characteristic of the“spray G”injector was studied by the computational fluid dynamics(CFD)simulation,and the sensitivity of cycle fuel mass to the conicity and entrance radius of the nozzle ho...The nozzle inner-flow characteristic of the“spray G”injector was studied by the computational fluid dynamics(CFD)simulation,and the sensitivity of cycle fuel mass to the conicity and entrance radius of the nozzle hole were analyzed.Results show that the inner conicity of nozzle hole inhibits the development of cavitation phenomena,and increases the injection rate.While the outer conicity of nozzle hole promotes the diffusion of cavita-tion,leading to reductions of the liquid volume fraction of the nozzle outlet and the local flow resistance of the nozzle hole.The sensitivity of cycle fuel mass to inner-cone nozzle hole is stronger than that of the outer-cone noz-zle,especially at the smaller hole conicity.The increase of injection pressure enhances the sensitivity of the injection characteristics to the nozzle hole structure,in which inner-cone nozzle has higher sensitivity coefficient than the outer-cone nozzle hole.However,the increase of injection pressure aggravates the offset of liquid jet to the nozzle axis of the outer-cone nozzle hole.With the increase of the inner conicity of nozzle,the sensitivity of the injection characteristics to the entrance radius of the hole decreases.With the increase of the outer conicity of nozzle hole,the sensitivity of the injection characteristics to the entrance radius of the hole increases.展开更多
基金Foundation item： Project（2011CB707201） supported by the National Basic Research Program of China Project（10JJ5058） supported by the Natural Science Foundation of Hunan Province, China
文摘To improve the energy utilization efficiency of internal combustion （IC） engine, exergy analysis was conducted on a passenger car gasoline engine. According to the thermodynamic theory of IC engine, in-cylinder exergy balance model was built. The working processes of gasoline engine were simulated by using the GT-power. In this way, the required parameters were calculated and then gasoline engine exergy balance was obtained by programming on computer. On this basis, the influences of various parameters on exergy balance were analyzed. Results show that, the proportions of various forms of exergy in gasoline engine from high to low are irreversible loss, effective work, exhaust gas exergy and heat transfer exergy. Effective exergy proportion fluctuates with cylinder volumetric efficiency at full load, while it always increases with break mean effective pressure （BMEP） at part load. Exhaust gas exergy proportion is more sensitive to speed, and it increases with speed increasing except at the highest speed. The lower proportion of heat transfer exergy appears at high speed and high load. Irreversible loss is mainly influenced by load. At part load, higher BMEP results in lower proportion of irreversible loss; at full load, the proportion of irreversible loss changes little except at the highest speed.
文摘The chemical detection of gasoline traces in fire debris is a challenge requiring highly sensitive,hyphenated analytical systems.The gas chromatography-mass spectrometry is suitable for the task.In this study,GC-MS were optimized to identify gasoline in simulated fire.And it was successful to apply this method to detect the gasoline in fire debris.
文摘Gasoline and its residues were examined by GC-MS technology.The method can be used to distinguish gasoline and its residues under the nature,combustion and volatility conditions,respectivesy.It can be provide useful information in criminal cases.
文摘This coming September will mark the 90th birthday of Academician Wanzhen LU,one of the best scientists in the field of analytical chemistry and petroleum chemistry both in China and around the world.Academician LU was born in Tianjin,Peoples’Republic of China on September 29,1924.Her father is a famous
文摘Trace gasoline residual analysis and identification is often applied in criminal analysis of arson,explosion,murder e.g..We analysis the trace gasoline in medium with SPME and GC-MS,that can identify the trace gasoline residual exactly through analyzing the mass spectrum of chromatogram peaks characters of alkenes,alkyl benzene,indene compounds,and naphthyl compounds,which are from the medium and burning medium.
文摘The structure of elemental sulfur (S0) in naphtha and gasoline was studied basing on that a new analytical method for determination of S0 was developed using gas chromatography-mass spectrometry (GC-MS).The test showed that the structure of S0 has changed and a small quantity of S2,S6,S7 has resulted and the mass proportion of S2∶S6∶S7∶S8 was 0.13:0.05:0.04:1.00 under the analysis condition.So the change of S0 structure with temperature had no effect on its quantity analysis.
文摘The nozzle inner-flow characteristic of the“spray G”injector was studied by the computational fluid dynamics(CFD)simulation,and the sensitivity of cycle fuel mass to the conicity and entrance radius of the nozzle hole were analyzed.Results show that the inner conicity of nozzle hole inhibits the development of cavitation phenomena,and increases the injection rate.While the outer conicity of nozzle hole promotes the diffusion of cavita-tion,leading to reductions of the liquid volume fraction of the nozzle outlet and the local flow resistance of the nozzle hole.The sensitivity of cycle fuel mass to inner-cone nozzle hole is stronger than that of the outer-cone noz-zle,especially at the smaller hole conicity.The increase of injection pressure enhances the sensitivity of the injection characteristics to the nozzle hole structure,in which inner-cone nozzle has higher sensitivity coefficient than the outer-cone nozzle hole.However,the increase of injection pressure aggravates the offset of liquid jet to the nozzle axis of the outer-cone nozzle hole.With the increase of the inner conicity of nozzle,the sensitivity of the injection characteristics to the entrance radius of the hole decreases.With the increase of the outer conicity of nozzle hole,the sensitivity of the injection characteristics to the entrance radius of the hole increases.
