Entropy represents the dissipation rate of energy. Through direct numerical simulation （DNS） of supersonic compression ramp flow, we find the value of entropy is monotonously decreasing along the wall-normal directi...Entropy represents the dissipation rate of energy. Through direct numerical simulation （DNS） of supersonic compression ramp flow, we find the value of entropy is monotonously decreasing along the wall-normal direction no matter in the attached or the separated region. Based on this feature, a new version of Baldwin-Lomax turbulence model （BL-entropy） is proposed in this paper. The supersonic compression ramp and cavity-ramp flows in which the original Baldwin-Lomax model fails to get convergent solutions are chosen to evaluate the performance of this model. Results from one-equation Spalart-Allmaras model （SA） and two-equation Wilcox k-x model are also included to compare with available experimental and DNS data. It is shown that BLentropy could conquer the essential deficiency of the original version by providing a more physically meaningful length scale in the complex flows. Moreover, this method is simple, computationally efficient and general, making it applicable to other models related with the supersonic boundary layer.展开更多
Gardenblue and baldwin rabbiteye blueberry are the alien varieties. The physical and chemical indices of the fresh fruits of the two varieties were analyzed. The results showed that the sugar-acid ratio was higher in ...Gardenblue and baldwin rabbiteye blueberry are the alien varieties. The physical and chemical indices of the fresh fruits of the two varieties were analyzed. The results showed that the sugar-acid ratio was higher in gardenblue than in baldwin, and the content of anthocyanins was also higher in gardenblue than in baldwin, so the quality of gardenblue was better. The gardenblue wine has better quality than the baldwin wine, and the two kinds of wines both have good quality. Therefore, gardenblue and baldwin both are suitable for the brewing red wine as the raw material.展开更多
The authors have studied the effect of a magnetic field on Baldwin＇s rules. The authors have proposed a new mechanism that takes into account the effect of the angle and energy endo- or exo-cyclization. The authors p...The authors have studied the effect of a magnetic field on Baldwin＇s rules. The authors have proposed a new mechanism that takes into account the effect of the angle and energy endo- or exo-cyclization. The authors propose to extend the rule Bouldwin not only for sp^3-, sp^2- and sp- orbits, but and for d^1 - d^10 and f^1 - f^14 elements of I-VIII of the Periodic table.展开更多
1862年，一位名叫鲍德温(Dwight Hamilton Baldwin)的管风琴和小提琴教师在俄亥俄州辛辛那提市开了家乐器店。在接下来的二十五年里，BALDWIN逐渐成为美国中西部最大的钢琴零售商之一。1891年，第一台BALDWIN立式琴面世。l895年，推出...1862年，一位名叫鲍德温(Dwight Hamilton Baldwin)的管风琴和小提琴教师在俄亥俄州辛辛那提市开了家乐器店。在接下来的二十五年里，BALDWIN逐渐成为美国中西部最大的钢琴零售商之一。1891年，第一台BALDWIN立式琴面世。l895年，推出第一台五尺四寸的三角钢琴。展开更多
基金National Basic Research Program of China(No.2009CB724104)the Innovation Foundation of BUAA for Ph.D.Graduates(No.300521)
文摘Entropy represents the dissipation rate of energy. Through direct numerical simulation （DNS） of supersonic compression ramp flow, we find the value of entropy is monotonously decreasing along the wall-normal direction no matter in the attached or the separated region. Based on this feature, a new version of Baldwin-Lomax turbulence model （BL-entropy） is proposed in this paper. The supersonic compression ramp and cavity-ramp flows in which the original Baldwin-Lomax model fails to get convergent solutions are chosen to evaluate the performance of this model. Results from one-equation Spalart-Allmaras model （SA） and two-equation Wilcox k-x model are also included to compare with available experimental and DNS data. It is shown that BLentropy could conquer the essential deficiency of the original version by providing a more physically meaningful length scale in the complex flows. Moreover, this method is simple, computationally efficient and general, making it applicable to other models related with the supersonic boundary layer.
基金Supported by Guizhou Provincial and Municipal Scientific and Technological Cooperation Fund(SSKH[2014]06)
文摘Gardenblue and baldwin rabbiteye blueberry are the alien varieties. The physical and chemical indices of the fresh fruits of the two varieties were analyzed. The results showed that the sugar-acid ratio was higher in gardenblue than in baldwin, and the content of anthocyanins was also higher in gardenblue than in baldwin, so the quality of gardenblue was better. The gardenblue wine has better quality than the baldwin wine, and the two kinds of wines both have good quality. Therefore, gardenblue and baldwin both are suitable for the brewing red wine as the raw material.
文摘The authors have studied the effect of a magnetic field on Baldwin＇s rules. The authors have proposed a new mechanism that takes into account the effect of the angle and energy endo- or exo-cyclization. The authors propose to extend the rule Bouldwin not only for sp^3-, sp^2- and sp- orbits, but and for d^1 - d^10 and f^1 - f^14 elements of I-VIII of the Periodic table.
基金Supported by the National Social Science Foundation of China(04AJL007)the National Natural Science Foundation of China(30470298)+1 种基金the Specialized Research Fund for the Doctoral Program of Higher Education of China(20020730017)the Doctoral Fundation of Guangdong University of Technology(063035)
