Long-chain alcohols were considered to be promising alternative fuels and fuel additives. This study was aimed at figuring out the influences of blending long-chain alcohols with jet fuel on the macroscopic spray char...Long-chain alcohols were considered to be promising alternative fuels and fuel additives. This study was aimed at figuring out the influences of blending long-chain alcohols with jet fuel on the macroscopic spray characteristic. n-Butanol and n-pentanol were chosen as tested alternative fuels. A common-rail injection system was used to create high-pressure injection conditions. The Schlieren imaging system was used to capture spray processes. Results showed that with the addition of long-chain alcohols, the spray tip penetration and the peak spray tip velocity increased, whereas the spray cone angle and the spray area decreased. Comparisons between those macroscopic spray characteristics of AKB blends and AKP blends were also conducted. Compared to AKB blends, AKP blends showed similar spray tip penetration, larger peak tip velocity, smaller spray cone angle, and smaller spray area.展开更多
The influence of thermal damage on macroscopic and microscopic characteristics of different rocks has received much attention in the field of rock engineering.When the rocks are subjected to thermal treatment,the chan...The influence of thermal damage on macroscopic and microscopic characteristics of different rocks has received much attention in the field of rock engineering.When the rocks are subjected to thermal treatment,the change of macroscopic characteristics and evolution of micro-structure would be induced,ultimately resulting in different degrees of thermal damage in rocks.To better understand the thermal damage mechanism of different rocks and its effect on the rock performance,this study reviews a large number of test results of rock specimens experiencing heating and cooling treatment in the laboratory.Firstly,the variations of macroscopic behaviors,including physical parameters,mechanical parameters,thermal conductivity and permeability,are examined.The variations of mechanical parameters with thermal treatment variables(i.e.temperature or the number of thermal cycles)are divided into four types.Secondly,several measuring methods for microstructure,such as polarizing microscopy,fluorescent method,scanning electron microscopy(SEM),X-ray computerized tomography(CT),acoustic emission(AE)and ultrasonic technique,are introduced.Furthermore,the effect of thermal damage on the mechanical parameters of rocks in response to different thermal treatments,involving temperature magnitude,cooling method and thermal cycle,are discussed.Finally,the limitations and prospects for the research of rock thermal damage are proposed.展开更多
基金supported by the National Natural Science Foundation of China(No.51376171)
文摘Long-chain alcohols were considered to be promising alternative fuels and fuel additives. This study was aimed at figuring out the influences of blending long-chain alcohols with jet fuel on the macroscopic spray characteristic. n-Butanol and n-pentanol were chosen as tested alternative fuels. A common-rail injection system was used to create high-pressure injection conditions. The Schlieren imaging system was used to capture spray processes. Results showed that with the addition of long-chain alcohols, the spray tip penetration and the peak spray tip velocity increased, whereas the spray cone angle and the spray area decreased. Comparisons between those macroscopic spray characteristics of AKB blends and AKP blends were also conducted. Compared to AKB blends, AKP blends showed similar spray tip penetration, larger peak tip velocity, smaller spray cone angle, and smaller spray area.
基金supported by the National Key Research and Development Plan(Grant No.2022YFC2905700)Natural Science Foundation of Anhui Province(Grant No.2208085ME120)Key Research and Development Plan of Anhui Province(Grant No.2022m07020001).
文摘The influence of thermal damage on macroscopic and microscopic characteristics of different rocks has received much attention in the field of rock engineering.When the rocks are subjected to thermal treatment,the change of macroscopic characteristics and evolution of micro-structure would be induced,ultimately resulting in different degrees of thermal damage in rocks.To better understand the thermal damage mechanism of different rocks and its effect on the rock performance,this study reviews a large number of test results of rock specimens experiencing heating and cooling treatment in the laboratory.Firstly,the variations of macroscopic behaviors,including physical parameters,mechanical parameters,thermal conductivity and permeability,are examined.The variations of mechanical parameters with thermal treatment variables(i.e.temperature or the number of thermal cycles)are divided into four types.Secondly,several measuring methods for microstructure,such as polarizing microscopy,fluorescent method,scanning electron microscopy(SEM),X-ray computerized tomography(CT),acoustic emission(AE)and ultrasonic technique,are introduced.Furthermore,the effect of thermal damage on the mechanical parameters of rocks in response to different thermal treatments,involving temperature magnitude,cooling method and thermal cycle,are discussed.Finally,the limitations and prospects for the research of rock thermal damage are proposed.