摘要：The high pressure waves generated due to muzzle blast flow of tank gun during firing is a critical issue to examine. The impulsive noise from the gun has various negative effects such as damage of human bodies, damage of structures, creating an environmental, social problem and also military problems such as exposure of location of troops. This high pressure impulsive sound, generated during the blast flow, was studied and attenuated. An axisymmetric computational domain was constructed by employing Spalart Allmaras turbulence model. Approximately 90% of pressure and 20 dB of sound level are reduced due to the use of the three baffle silencer at the muzzle end of the gun barrel, in comparison with the tank gun without silencer. Also, the sound pressure level at different points in the ambient region shows the same attenuation in results. This study will be helpful to understand the blast wave characteristics and also to get a good idea to design silencer for large caliber weapon system.

摘要：Short suspension system has an indispensable effect on vehicle handling and ride,so,optimization of vehicle suspension system is one of the most effective methods,which could considerably enhance the vehicle stability and *** control,stability maintenance and ride comfort improvement are fundamental issues in design of suspension system of off-road *** this work,a dependent suspension system mostly used in off-road vehicles is modeled using Trucksim ***,geometric parameters of suspension system are optimized using integrated anti-roll bar and coiling spring in a way that ride comfort,handling and stability of vehicle are *** simulation results of suspension system and variations of geometric parameters due to road roughness and different steering angles are presented in Trucksim and effects of optimization of suspension system during various driving maneuvers in both optimized and un-optimized conditions are *** simulation results indicate that the type of suspension system and geometric parameters have significant effect on vehicle performance.

摘要：Biochar is a solid material obtained from the carbonization of biomass. Biochar is used on agricultural lands as a soil amendment to improve the fertility of the soils. Currently the most common method of producing biochar is through biochar stoves. There are two basic stove operations in the production of biochar. The first type of stove produces biochar by direct combustion of biomass. Here biomass is burnt inside a chamber in an oxygen limited environment. The resulting residue is the bio-char. The second type involves burning the biomass in one chamber and housing the biomass to be charred in the annular portion of an outer chamber. Heat is transferred from the burning fuel on the inner chamber to the material to be charred in the outer chamber. While the process of biochar production in these stoves is known, the basic principles of the stove design are not readily available. The design methodology for both the types was developed from first principles. Prototypes of both types were constructed based on the design developed and tested. The paper lists the basic principles in the design of biochar stoves and the test results.

摘要：Cavity resonance noise of passenger car tires is generated by interacting excitation between a tire structure and the fill gas (air), and generally lies in a frequency range of 200?250 Hz. As such, this noise is strongly perceived and may be a serious source of driver annoyance. Thus, many studies regarding the cavity noise mechanism and its reduction have already been conducted. In this work, a vibro-acoustic coupled analysis was conducted between a tire structure and air cavity. Using this analysis, we can more accurately simulate the tire noise performance in the region of the cavity resonance frequency. An analysis of the effects of variation of tire contour design factors was conducted, using design-of-experiments methods. Finally, a multi-objective optimization was performed using in-house codes to reduce the cavity noise level while minimizing the loss of other performances, such as diminished ride comfort and handling caused by the variations of contour. As a result of this optimization, an optimized contour shape was derived, which satisfied the multi-objective performances.

摘要：Layered double hydroxides(LDHs),a class of two-dimensional(2D)brucite-like layers,have been effectively applied in diverse ***,the current synthesis methods restrict the in situ scaling-up and tunable production of LDH-based *** by the growing characteristic of“Bryophyllum pinnatum”,a sacrificial co-sputtered Zn-Al transition layer was introduced for the first time to in situ grow a scalable-manufactured and thickness-controllable LDH film on arbitrary substrate materials with flexible shapes through“partial dissolution”and“solution infiltration”*** LDH films could be tailored by the creative regulation of the component,structure and surface state of the transition *** showed that the as-prepared LDH film had strong mechanical robustness under harsh abrasion conditions due to its large thickness and multi-level ***,a series of galvanic couple model experiments based on Zn/Al single-metal transition layers were designed to solve the real-time monitoring issue in the complex hydrothermal *** work not only develops a new strategy to design and grow in situ LDH films with multifaceted features,but also reveals sophisticated LDH formation ***,the findings of this study may broaden the practical application of LDH-based materials toward advanced and smart devices.

摘要：Tire force and moment testing is a valuable way of quantifying the performance of a tire. The data collected from such testing is also used by many researchers for vehicle dynamic simulation studies as well as chassis control system development. Although various studies have claimed correlation between data from rolling road type machines and road testing trailers, the claim only extends for on-road conditions. Many military vehicles as well as agricultural vehicles operate in an environment which requires new levels of tire test data. This paper will discuss the design and testing of a portable trailer tire test rig. This rig was conceived and constructed for use on both on- and off-road driving surfaces and is also fitted for wet-road testing. The rig will eventually be used to collect tire data on various tire sizes both on and off-road on various road surfaces, such as grass, asphalt, concrete, and gravel for varying speeds, pressures, loads, and slip angles. The data will be used to develop a modified Pacejka Magic Formula Tire Model that can be used for conducting simulation in both on and off-road conditions.