Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Longbao Zhou is active.

Publication


Featured researches published by Longbao Zhou.


Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering | 1999

Study of combustion characteristics of a compression ignition engine fuelled with dimethyl ether

Zuohua Huang; Hewu Wang; Hao Chen; Longbao Zhou; Deming Jiang

Abstract This paper presents the combustion characteristics of a light-duty direct-injection diesel engine operating on dimethyl ether (DME). The indicated pressure diagrams and injector needle lifts are recorded and the combustion characteristics are demonstrated and compared with those of an engine operated on diesel fuel. The experimental and calculated results show that the DME engine has a longer delay of injection and duration of injection, a lower maximum cylinder pressure and rate of pressure rise, as well as a shorter ignition delay compared with those of a diesel engine. The DME engine has a low mechanical load and combustion noise, a fast rate of diffusion combustion and a shorter combustion duration than that of a diesel engine. It has the ideal pattern of compression ignition engine heat release.


Proceedings of the Institution of Mechanical Engineers. Part D, Journal of automobile engineering | 2000

Study on the performance and emissions of a compression ignition engine fuelled with dimethyl ether

Hewu Wang; Longbao Zhou; Deming Jiang; Zuohua Huang

Abstract The paper presents the research results of a light-duty direct injection diesel engine operating on dimethyl ether (DME). The effects of the main parameters of the combustion system, such as plunger diameter, nozzle type, fuel delivery advance angle, protruding distance of the nozzle tip from the bottom plane of the cylinder head and swirl ratio, on the performance of the DME engine are investigated. The indicator diagrams are taken after optimizing the combustion system and characteristics of combustion and emissions are measured for DME and diesel operation. The results show that, by adding a pressure pump in the fuel supply system, the vapour lock of DME in the fuel system is eliminated. The engine runs smoothly on DME over a wide range of speeds and loads. The effective thermal efficiency of the DME engine is 3 per cent higher than that of the diesel engine, and a low rate of pressure rise, low combustion noise, smokeless combustion and low NO x emissions of the DME engine can be achieved. The results demonstrate good characteristics in reducing emissions for a diesel engine operating on DME.


Combustion Science and Technology | 1996

An Investigation on Simulation Models and Reduction Methods of Unburned Hydrocarbon Emissions in Spark Ignition Engines

Zuohua Huang; Keyu Pan; Jijun Li; Longbao Zhou; Deming Jiang

In this paper, the formation mechanisms of unburned hydrocarbons in the cylinder of spark ignition engine are investigated and the prediction model of unburned hydrocarbon formation and desorption in top land crevice, in the layers of lubricating oil on the cylinder liner and in deposits on the combustion chamber in spark ignition engines are established. The effects of different top land crevice widths, engine speeds, air fuel ratios and spark advance angles on engine exhaust unburned hydrocarbons are investigated. It is shown that the optimum width of engine top land crevice is 0.32 mm (1.3 times of the two wall quenching distance), thus the flame can get into the bottom of crevice and burns out all of the accumulated unburned hydrocarbons in it, consequently the engine exhaust hydrocarbons can be greatly reduce by 35∼50% and with less penalty on engine power output and fuel economy 0.5 ∼ 1.5% loss in power output and 1 ∼ 3% loss in fuel economy), the predicting values by the models match well with the ...


Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering | 1998

Investigation into hydrocarbon emissions from crevice and oil film during cold start and idling periods in a spark ignition engine

Zuohua Huang; J Pang; Keyu Pan; Deming Jiang; Longbao Zhou; Z L Yang

Abstract In order to understand better the process of hydrocarbon formation and the effect of the top-land crevice and the oil layer of the cylinder liner on unburned hydrocarbons during cold start and idling periods, the temperature of the piston top-land and liner was measured. Based on the measured results, the amount of unburned hydrocarbons from the crevice and liner has been predicted. It was found that the temperature of the piston top-land and cylinder liner took about 150-200 s to reach its equilibrium state as the engine started up. The concentration of hydrocarbons from the top-land crevice and from the oil layer will be reduced to 40 and 75 per cent of its initial value respectively. It is considered that a reduction in piston thermal capacity can reduce the total unburned hydrocarbons during this transient period owing to quick minimization of the top-land crevice volume and rapid increase in mixture temperature in the crevice region.


Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering | 1996

Effect of Top Land Width and Engine Operating Conditions on Exhaust Hydrocarbon Emissions from a Spark Ignition Engine

Zuohua Huang; Keyu Pan; Longbao Zhou; Deming Jiang

In this paper, the formation mechanisms of unburnt hydrocarbons in the cylinder of a spark ignition engine are investigated and the effects of various top land crevice widths, engine speeds, air–fuel ratios and spark advance angles on engine exhaust hydrocarbons are investigated. The effects of engine top land crevice width on power output and fuel economy are also analysed. It is shown that the optimum engine top land crevice width is 0.32 mm (1.3 times the two surface quench distances), thus the flame can get into the bottom of the crevice and burns out all of the accumulated unburnt hydrocarbons in it, consequently the engine exhaust hydrocarbons can be greatly reduced by 35–50 per cent with less penalty on engine power output and fuel economy (0.5–1.5 per cent loss in power output and 1 ∼ 3 per cent increase in fuel economy).


Combustion Science and Technology | 1998

Prediction and Experimental Study on Hydrocarbon Emissions from Combustion Chamber Deposits in a Spark Ignition Engine

Zuohua Huang; H. Guo; Keyu Pan; Longbao Zhou; Deming Jiang

To understand the effect of deposit in combustion chamber on engine-out hydrocarbon emissions, a two-zone model which predicts the hydrocarbon emissions contributed from combustion chamber deposits is presented and test one cylinder spark ignition engine is used to accumulate the combustion chamber deposit. The experiments are conducted on hydrocarbon emissions under various operating conditions in the presence of combustion chamber deposits. The model can successfully predict the hydrocarbons contributed from combustion chamber deposits on various engine operating conditions. The experimental results show that there exists an equilibrium thickness of deposits in combustion chamber if engine operates for a certain period of time. The combustion chamber deposits will contribute 20 ∼ 30 percent of the engine-out hydrocarbon emissions by the investigation.


Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering | 2000

INVESTIGATION ON EMISSION CHARACTERISTICS OF A COMPRESSION IGNITION ENGINE WITH OXYGENATED FUELS AND EXHAUST GAS RECIRCULATION

Hewu Wang; Zuohua Huang; Longbao Zhou; Deming Jiang; Z L Yang


SAE transactions | 1995

Evaluation of the thermodynamic process of indirect injection diesel engines by the First and Second Law

Jianwen Li; Longbao Zhou; Keyu Pan; Deming Jiang; J.O. Chae


Transactions of Csice | 2004

Estimation of DME Thermo-Physical Properties by Molecule Theory

Xi-Bin Wang; Deming Jiang; Longbao Zhou; Keyu Pan


SAE transactions | 1995

Frequency Analysis Technique for Intake and Exhaust Manifold Design

Jianwen Li; Longbao Zhou; Deming Jiang; Keyu Pan

Collaboration


Dive into the Longbao Zhou's collaboration.

Top Co-Authors

Avatar

Deming Jiang

Xi'an Jiaotong University

View shared research outputs
Top Co-Authors

Avatar

Keyu Pan

Xi'an Jiaotong University

View shared research outputs
Top Co-Authors

Avatar

Zuohua Huang

Xi'an Jiaotong University

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Jianwen Li

Xi'an Jiaotong University

View shared research outputs
Top Co-Authors

Avatar

H. Guo

Xi'an Jiaotong University

View shared research outputs
Top Co-Authors

Avatar

Hao Chen

Xi'an Jiaotong University

View shared research outputs
Top Co-Authors

Avatar

Jijun Li

Xi'an Jiaotong University

View shared research outputs
Top Co-Authors

Avatar

Xi-Bin Wang

Xi'an Jiaotong University

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge