Standard test method for low temperature , low shear rate , viscosity temperature dependence of lubricating oils using a temperature - scanning technique 采用温度扫描技术的润滑油的低温低剪切率粘性温度关系的标准试验方法
If the materials are degraded in the event of high temperature and high shearing rate , the melt viscosity will decrease due to the breaking up of the molecular bonds 如果材料因高温或高剪切率加工而降解,熔胶粘度会因分子链断裂而降低
The molecules of soft sections of sebs elastomers are satuated and will not be oxidized . the stability will not be affected by manufacturing in high temperature and high shearing rate Sebs弹体软质段分子饱和,不会被氧化,高温或高剪切率加工不影响稳定性
Due to the structure difference in the molecules of soft sections between sbs and sebs elastomers , the viscosity and shear rate is of significant variation 由于sbs与sebs弹体中间的软质段分子结构不同,其相对剪切率的粘度特性viscosity shear rate也有显著的差异
But , the melt viscosity of the sbs and sebs elastomers is highly affected by the shear rate inside the barrel but it is not sensitive to the temperature inside the barrel 但sbs与sebs弹体的熔胶粘度melt viscosity非常容易被炮筒内剪切率shear rate影响,反而对炮筒内的温度不太敏感
The molecules of soft sections of sbs elastomers are not satuated and is easily to be oxidized . it is highly possible to create degradation by manufacturing in high temperature and high shearing rate Sbs软质段分子段有不饱和键,容易被氧化,高温或高剪切率加工产生材料降解degradation可能性高
The evolutional process of the wall impulses in different reynolds number , grid schemes , and various flows are studied , and the generative and development mechanisms of the turbulent spots in the wall reg ion of a shear flow are analyzed . the results show generation and development of the turbulent spots are closely relative to the reynolds number , initial disturbance and shear rate of the velocity , and are consistent with experiment results 研究在不同雷诺数、网格和不同流动中壁面扰动的演化过程,分析近壁剪切流动中湍斑的形成和发展机理,展示了近壁剪切流动中湍斑的产生和发展与雷诺数、初始扰动和速度剪切率等密切相关。