Super-knock suppression for highly turbocharged gasoline engines using lean mixture control strategy with the same energy density

Biobutanol is a renewable, less polluting, and potentially viable alternative fuel to conventional gasoline. Biobutanol can be produced from same sources as bioethanol, and it has many advantages over the widespread bioethanol. This paper systematically analyzes biobutanol fuel as an alternative to bioethanol in alcohol–gasoline mixtures and the physicochemical properties. Based on the conducted analyses, it was found that biobutanol mixtures have a more suitable behavior of vapor pressure without the occurrence of azeotrope, do not form a separate phase in lower temperature, it has higher energy density, but slightly reduce the octane number and a have higher viscosity. However, in general, biobutanol has many advantageous properties that could allow its use in gasoline engines instead of the commonly used bioethanol.

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A novel predictive semi-physical feed-forward turbocharging system transient control strategy based on mean-value turbocharger model

International Journal of Engine Research ◽

10.1177/1468087416670052 ◽

2016 ◽

Vol 18 (8) ◽

pp. 765-775 ◽

Cited By ~ 5

Author(s):

Huayin Tang ◽

Colin Copeland ◽

Sam Akehurst ◽

Chris Brace ◽

Peter Davies ◽

...

Keyword(s):

Control Strategy ◽

Control Strategies ◽

Mean Value ◽

Variable Geometry ◽

Gasoline Engines ◽

Engine Model ◽

Turbocharging System ◽

Transient Control ◽

Variable Geometry Turbine ◽

The One

Variable geometry turbine is a technology that has been proven on diesel engines. However, despite the potential to further improve gasoline engines’ fuel economy and transient response using variable geometry turbine, controlling the variable geometry turbine during transients is challenging due to its highly non-linear behaviours especially on gasoline applications. After comparing three potential turbocharger transient control strategies, the one that predicts the turbine performances for a range of possible variable geometry turbine settings in advance was developed and validated using a high-fidelity engine model. The proposed control strategy is able to capture the complex transient behaviours and achieve the optimum variable geometry turbine trajectories. This improved the turbocharger response time by more than 14% compared with a conventional proportional–integral–derivative controller, which cannot achieve target turbocharge speed in all cases. Furthermore, the calibration effort required can be significantly reduced, offering significant benefits for powertrain developers. It is expected that the structure of this transient control strategy can also be applied to complex air-path systems.

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Energy Evolution Pattern and Roof Control Strategy in Non-Pillar Mining Method of Goaf-Side Entry Retaining by Roof Cutting—A Case Study

Sustainability ◽

10.3390/su11247029 ◽

2019 ◽

Vol 11 (24) ◽

pp. 7029 ◽

Cited By ~ 1

Author(s):

Lifeng Li ◽

Gan Li ◽

Weili Gong ◽

Jiong Wang ◽

Huilin Deng

Keyword(s):

Energy Density ◽

Large Deformation ◽

Control Strategy ◽

Calculation Model ◽

Surrounding Rock ◽

Mining Method ◽

Energy Evolution ◽

Working Face ◽

Evolution Pattern ◽

Pillar Mining

This article focuses on the energy density alteration during non-pillar mining method of goaf-side entry retaining by roof cutting (GERRC) and adjacent working face mining. We also studied the support control strategy of goaf-side roadway. Numerical calculation model is established, and the parameters of the model are verified by the measured advance abutment pressure and numerical solution. Based on the numerical model, the energy density during mining is studied. It is found that the whole energy evolution pattern of the goaf side entry during the two adjacent working face mining includes: the original rock energy, the advance energy of the current working face, the dynamic lateral abutment energy caused by strata movement, the lateral abutment energy of the adjacent working face. The support body failure and surrounding rock large deformation phenomenon often occur in goaf side roadway, which is influenced by multiple energy disturbances. Research shows that strong stress disturbance of surrounding rock generates in front of the working face 23 m and behind of working face 60 m in GERRC method. In the second goaf-side entry retaining, the range is in front of the working face 47 m. The evolution law of energy field puts forward the strategy of using the high constant resistance and large deformation (CRLD) anchor cable and procured preferable effect.

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