An experimental system was set up to measure the temperature, pressure, heat transfer rate and mass flow rate in a semi-open two-phase thermosyphon. The behaviors of a semi-open two-phase thermosyphon during startup, ...An experimental system was set up to measure the temperature, pressure, heat transfer rate and mass flow rate in a semi-open two-phase thermosyphon. The behaviors of a semi-open two-phase thermosyphon during startup, shutdown and lack of water were studied to get complete understanding of its thermal characteristics. The variation of wall temperature, heat-exchange condition and pressure fluctuations of semi-open two-phase thermosyphons showed that the startup of SOTPT needs about 60-70 min; the startup speed of SOTPT is determined by the startup speed of the condensation section; the average pressure in the heat pipe is equal to the environmental pressure usually; the shutdown of SOTPT needs about 30-50min; a semi-open two-phase thermosyphon has good response to lack of water accident.展开更多
Given a mapping f between continua.Let 2f and C(f) mean the induced mappings between hyperspaces.Relations are studied under the conditions:f is semi-open(almost open,respectively),2f is semi-open(almost open,respecti...Given a mapping f between continua.Let 2f and C(f) mean the induced mappings between hyperspaces.Relations are studied under the conditions:f is semi-open(almost open,respectively),2f is semi-open(almost open,respectively) and C(f) is semi-open(almost open,respectively).展开更多
This paper focuses on the heat transfer performance of semi-open heat pipe which is a new type of heat pipe. After analyzing its condensation heat transfer mechanisms theoretically, several semi-open heat pipes in dif...This paper focuses on the heat transfer performance of semi-open heat pipe which is a new type of heat pipe. After analyzing its condensation heat transfer mechanisms theoretically, several semi-open heat pipes in different length ratios and upper hole diameters are studied experimentally and compared with the same dimensions closed heat pipes. Experimental results show that the heat transfer performance of semi-open heat pipe becomes better by increasing heat transfer rate. At the first transitional point, the heat transfer performance of semi-open heat pipe approaches the level of the closed heat pipe. It is suitable to choose upper small hole about 1 mm in diameter and length ratio larger than 0.6 for the semi-open heat pipe.展开更多
In this study, we tried to improve the performance by giving a pre-swirling flow to the radial inflow that occurred in the semi-opened axial fan. In addition, the flow fields of rotor outlet were clarified experimenta...In this study, we tried to improve the performance by giving a pre-swirling flow to the radial inflow that occurred in the semi-opened axial fan. In addition, the flow fields of rotor outlet were clarified experimentally, and the effect of pre-swirling flow was considered. The experiment was carried out using a performance test wind tunnel with a square cross section of 880 mm. Three types of casings were prepared, in which the blade tip protruded 0%, 20%, and 40% of the meridional chord length. They were called R25, R15, and R05, respectively, in the casing bellmouth model code. Guide blades for generating a pre-swirling flow were installed on the vertical wall surface of the casing. In addition, a vertical wall was installed 60% upstream of the meridional chord length as an obstacle to prevent axial inflow. The velocity fields of the rotor outlet were measured using a hot-wire anemometer. From the results, the pre-swirling flow did not significantly affect the fan performance. When there was no obstacles wall upstream, there was a partial increase in efficiency, but the difference was not so large. When there was an obstacle wall upstream, the efficiency increased overall in the case of R15, but in the case of R05, the efficiency increased only in the low flow rate region, and conversely decreased in the high flow rate region. By observing the blade outlet flow fields when the performance was improved, it was confirmed that the influence of the tip leakage vortex was weakened.展开更多
The Jurassic coal-measure source rocks in the Junggar Basin have drawn considerable attention in recent years. In our hydrocarbon thermal simulation experiments of these rocks, we found that the dark mudstone evaluate...The Jurassic coal-measure source rocks in the Junggar Basin have drawn considerable attention in recent years. In our hydrocarbon thermal simulation experiments of these rocks, we found that the dark mudstone evaluated as good source rock, had a much lower hydrocarbon generation capacity than the coal and carbonaceous mudstone, evaluated as poor source rock. Based on this background, we performed Fourier transform infrared spectroscopy(FTIR) and combined the results of semi-open thermal simulation experiments to explore the association between the molecular structure and hydrocarbon production capacity, with the aim of obtaining a new understanding of hydrocarbon potential of Jurassic coal-measure source rocks from the perspective of molecular structure. The results indicate that coals exhibit lower condensation of aromatic structures and higher relative abundance of aliphatic structures with a higher degree of branched chaining than mudstones and carbonaceous mudstones. Apparent aromaticity(f_a), aromatic abundance parameter I, and degree of condensation(DOC) are negatively correlated with organic matter abundance. The aliphatic structural parameter H demonstrates a substantial positive correlation with organic matter abundance. Furthermore, aliphatic relative abundance factor A is associated with the type of organic matter;the better is the type of the organic matter, the larger is the A value. The combination of the molecular structures with the thermal simulation results shows that the aliphatic hydrogen enrichment of selected carbonaceous mudstone is similar to that of coal. However, the relative abundance of the aliphatic group of it is high, and the DOC of the aromatic structure is low, making the hydrocarbon generation base stronger and easier to crack. Thus, the hydrocarbon generation capacity of carbonaceous mudstone is slightly higher than that of coal. Mudstone has low H and I values, and the DOC is high, indicating that its hydrocarbon base is low, so it has low hydrocarbon generation capacity. Therefore, the molecular structure is closely associated with the hydrocarbon potential of coal-measure source rocks. When evaluating the qualities of coal-measure source rocks, the influence of molecular structure on these rocks should be considered.展开更多
为了对鄂尔多斯盆地古生界奥陶系风化壳中天然气的主要来源进行判识,采取盆地内的低熟煤作为石炭系本溪组气源岩的未成熟样品进行了不同恒温条件下的半开放体系热解实验。实验结果表明:①在不恒温时,在每个温度点上样品没有充分反应,到...为了对鄂尔多斯盆地古生界奥陶系风化壳中天然气的主要来源进行判识,采取盆地内的低熟煤作为石炭系本溪组气源岩的未成熟样品进行了不同恒温条件下的半开放体系热解实验。实验结果表明:①在不恒温时,在每个温度点上样品没有充分反应,到更高温度点经过低温范围时样品会再次生烃,在高温度点产出的甲烷包含经历低温阶段时产生的甲烷,这与封闭实验的生烃机制类似;②恒温120 m in时,在每个温度点恒温时间足够长,样品充分反应,到更高温度点经过低温范围时样品不再生烃,在高温度点产出的甲烷是低温度点和高温度点之间产生的甲烷,这与开放实验的生烃机制类似;③乙烷到戊烷的产量远远小于甲烷的产量,在每一个温度点这些烃类均已生成殆尽,到下一个更高温度点经过低温范围时,其不再生成,下一高温度点得到的这些烃类只是下一个低温度点和高温度点之间的产物,这与开放体系的生烃机制类似。展开更多
文摘An experimental system was set up to measure the temperature, pressure, heat transfer rate and mass flow rate in a semi-open two-phase thermosyphon. The behaviors of a semi-open two-phase thermosyphon during startup, shutdown and lack of water were studied to get complete understanding of its thermal characteristics. The variation of wall temperature, heat-exchange condition and pressure fluctuations of semi-open two-phase thermosyphons showed that the startup of SOTPT needs about 60-70 min; the startup speed of SOTPT is determined by the startup speed of the condensation section; the average pressure in the heat pipe is equal to the environmental pressure usually; the shutdown of SOTPT needs about 30-50min; a semi-open two-phase thermosyphon has good response to lack of water accident.
文摘Given a mapping f between continua.Let 2f and C(f) mean the induced mappings between hyperspaces.Relations are studied under the conditions:f is semi-open(almost open,respectively),2f is semi-open(almost open,respectively) and C(f) is semi-open(almost open,respectively).
文摘This paper focuses on the heat transfer performance of semi-open heat pipe which is a new type of heat pipe. After analyzing its condensation heat transfer mechanisms theoretically, several semi-open heat pipes in different length ratios and upper hole diameters are studied experimentally and compared with the same dimensions closed heat pipes. Experimental results show that the heat transfer performance of semi-open heat pipe becomes better by increasing heat transfer rate. At the first transitional point, the heat transfer performance of semi-open heat pipe approaches the level of the closed heat pipe. It is suitable to choose upper small hole about 1 mm in diameter and length ratio larger than 0.6 for the semi-open heat pipe.
文摘In this study, we tried to improve the performance by giving a pre-swirling flow to the radial inflow that occurred in the semi-opened axial fan. In addition, the flow fields of rotor outlet were clarified experimentally, and the effect of pre-swirling flow was considered. The experiment was carried out using a performance test wind tunnel with a square cross section of 880 mm. Three types of casings were prepared, in which the blade tip protruded 0%, 20%, and 40% of the meridional chord length. They were called R25, R15, and R05, respectively, in the casing bellmouth model code. Guide blades for generating a pre-swirling flow were installed on the vertical wall surface of the casing. In addition, a vertical wall was installed 60% upstream of the meridional chord length as an obstacle to prevent axial inflow. The velocity fields of the rotor outlet were measured using a hot-wire anemometer. From the results, the pre-swirling flow did not significantly affect the fan performance. When there was no obstacles wall upstream, there was a partial increase in efficiency, but the difference was not so large. When there was an obstacle wall upstream, the efficiency increased overall in the case of R15, but in the case of R05, the efficiency increased only in the low flow rate region, and conversely decreased in the high flow rate region. By observing the blade outlet flow fields when the performance was improved, it was confirmed that the influence of the tip leakage vortex was weakened.
基金co-funded by the National Natural Science Foundation of China (Grant Nos. 42372160, 42072172)Shandong Province Natural Science Fund for Distinguished Young Scholars (Grant No. JQ201311)the Graduate Scientific and Technological Innovation Project financially supported by Shandong University of Science and Technology (Grant No. SDKDYC190313)。
文摘The Jurassic coal-measure source rocks in the Junggar Basin have drawn considerable attention in recent years. In our hydrocarbon thermal simulation experiments of these rocks, we found that the dark mudstone evaluated as good source rock, had a much lower hydrocarbon generation capacity than the coal and carbonaceous mudstone, evaluated as poor source rock. Based on this background, we performed Fourier transform infrared spectroscopy(FTIR) and combined the results of semi-open thermal simulation experiments to explore the association between the molecular structure and hydrocarbon production capacity, with the aim of obtaining a new understanding of hydrocarbon potential of Jurassic coal-measure source rocks from the perspective of molecular structure. The results indicate that coals exhibit lower condensation of aromatic structures and higher relative abundance of aliphatic structures with a higher degree of branched chaining than mudstones and carbonaceous mudstones. Apparent aromaticity(f_a), aromatic abundance parameter I, and degree of condensation(DOC) are negatively correlated with organic matter abundance. The aliphatic structural parameter H demonstrates a substantial positive correlation with organic matter abundance. Furthermore, aliphatic relative abundance factor A is associated with the type of organic matter;the better is the type of the organic matter, the larger is the A value. The combination of the molecular structures with the thermal simulation results shows that the aliphatic hydrogen enrichment of selected carbonaceous mudstone is similar to that of coal. However, the relative abundance of the aliphatic group of it is high, and the DOC of the aromatic structure is low, making the hydrocarbon generation base stronger and easier to crack. Thus, the hydrocarbon generation capacity of carbonaceous mudstone is slightly higher than that of coal. Mudstone has low H and I values, and the DOC is high, indicating that its hydrocarbon base is low, so it has low hydrocarbon generation capacity. Therefore, the molecular structure is closely associated with the hydrocarbon potential of coal-measure source rocks. When evaluating the qualities of coal-measure source rocks, the influence of molecular structure on these rocks should be considered.
文摘为了对鄂尔多斯盆地古生界奥陶系风化壳中天然气的主要来源进行判识,采取盆地内的低熟煤作为石炭系本溪组气源岩的未成熟样品进行了不同恒温条件下的半开放体系热解实验。实验结果表明:①在不恒温时,在每个温度点上样品没有充分反应,到更高温度点经过低温范围时样品会再次生烃,在高温度点产出的甲烷包含经历低温阶段时产生的甲烷,这与封闭实验的生烃机制类似;②恒温120 m in时,在每个温度点恒温时间足够长,样品充分反应,到更高温度点经过低温范围时样品不再生烃,在高温度点产出的甲烷是低温度点和高温度点之间产生的甲烷,这与开放实验的生烃机制类似;③乙烷到戊烷的产量远远小于甲烷的产量,在每一个温度点这些烃类均已生成殆尽,到下一个更高温度点经过低温范围时,其不再生成,下一高温度点得到的这些烃类只是下一个低温度点和高温度点之间的产物,这与开放体系的生烃机制类似。
