Division of Advanced Research, University of Science and Technology of China, Senior Associate Professor Ting Ting, associate professor Zhai Zhigang and Professor Luo Xisheng, etc. made a series of new progresses in shock-induced interface instability experiment, and obtained the first shock wave shock The evolutionary images of the multimode interface reveal the laws and mechanisms underlying the instability and complex wave regimes of interfaces. A number of recent studies have been published on J. Fluid Mech. And Phys. Fluids. Shock-induced interface instability is a very complex multi-scale strong non-linear physics problem, which is one of the main directions of compressible turbulence mechanism research. It is also an important content of high energy density physics research. In astrophysics, inertial constraints ICF clean energy, space rocket engines, national defense frontier weapons and other fields have a wide range of applications and research value. Experimental research, laser inertial confinement fusion, electromagnetic sleeve implosion, explosive-driven metal materials and other methods costly, longer cycle, the diagnosis is difficult and difficult to carry out in large quantities. Therefore, under laboratory conditions, the shock wave loading fluid interface experiment has become an important research method. Due to the convergence of shock waves can produce high temperature and pressure, more in line with the actual engineering applications, international research focuses on the convergence of shock and interface interactions. According to Luo Xisheng, the experimental research on the interaction of shock wave and interface in shock tube needs to solve three major problems, namely, the generation of convergent shock wave, the formation of perfect controllable interface and the observation of fine flow field structure. Through long-term research, the research team broke through the two key technologies of "convergence shock generation" and "controllable interface formation", and took the lead in designing and constructing wedge converging shock wave tubes (Phys. Fluids, 2010, 22: 041701; Phys (J. Fluids, 2012, 24: 026101; Rev. Sci. Instrum. 2014, 85: 015107) and a semicircular converging shock tube (Phys. Fluids, 2015, 27: 091702) Fluid Mech. 2014, 757: 800-816; J. Fluid Mech. 2015, 773: 366-394). Using advanced flow field diagnostics, the evolution of a multimode interface under the impact of convergent shocks is first obtained internationally Developmental Rules and Mechanisms (J. Fluid Mech. 2015, 784: 225-251). In a convergent shockwave tube, a smooth arc-shaped shock interacts with the initial gas interface to produce a reflected shock and a transmitted shock, and any initial perturbations at the interface increase due to instability. Secretary Ting said that the shock wave induced by the interface under the instability of the development of plane shock wave are quite different. The results show that the convergence shock reaches the focal point through the interface to generate the local high-pressure and high-energy density region, which is then reflected rapidly and re-interacted with the interface to reverse the interface motion, resulting in a very complex wave structure in the flow field. During the whole process, the intensity of the shock wave constantly changes. The pressure disturbance and vorticity distribution in the flow field make the interface velocity and disturbance growth rate change with time. As a result, the convergence shock induced interface instability will on the one hand undermine the symmetry and uniformity of shock convergence to the aerodynamic focus and, on the other hand, will facilitate mixing between different fluids. The quantitative and evolutionary laws and mechanisms underlying the development of disturbances obtained from the study provide validated data and images for relevant numerical simulation programs and theories as well as reliable theory for practical applications such as the design of ICF pellets and the design of a space rocket engine combustor guide. The above research work has been funded by the National Natural Science Foundation of China and the Central University for basic scientific research. The experimental results of the shock shock multimode interface (left) and the single mode interface (right) are summarized Air Conditioner Spare Parts series mainly including all spare parts of air conditioners which are widely use in the a/c after-sales field, like compressor, remote controller, PCB board, sensor, motor, connecting pipe, copper pipe, capacitors., etc. Heat Protection Pipe,Air Conditioner Spare Parts,Universal Remote Controller,Universal Ac Remote Controller Foshan Dinghan Electrical Technology Co., Ltd , https://www.fsdinghanelectrical.com
February 13, 2024