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This paper tracks the latest development of UAV noise certification regulations in various countries, outlines the current airworthiness noise requirements, focuses on the overview of various UAV noise assessment methods, and analyses the characteristics and differences of the existing UAV noise evaluation methods in terms of evaluation indicators, measurement procedures and data correction. Combined with the existing domestic environmental protection requirements and noise pollution prevention requirements, as well as the requirements of the UAV superseding law, it can be expected that the impact of UAV noise on people will be an important part of the future UAV airworthiness certification, which will be an important guiding significance for states’ legislation and standardization.

Coordinated control of mode transition is an important part of the multi-mode hybrid vehicles' control strategy, combined with a vehicle torque distribution strategy to realize an optimal working condition of the power sources, as well as achieve smooth mode switching. This paper builds hybrid electric vehicle driveline dynamics model and depth analyzes drive mode transition process, coordinated control methods were provided to solve three types of mode switching, neural network algorithm was provided to estimate the engine torque. The results show that coordinated control can reduce torque fluctuations and decrease jerk during the transition of different modes to improve the vehicle drivability.

In order to achieve the best shifting performance, the traditional hybrid vehicles shift schedule design based on multi-parameter shift schedule, these shift methods can improve fuel economy and acceleration performance to a certain extent. but it is difficult to obtain the optimal performance because it is a compromise between power and economy shift schedule. This paper provides adaptive shift strategy based on driving style recognition to select the optimal shift schedule, thereby improving the dynamic performance of the vehicle as well as reduced fuel consumption.

The traditional energy management algorithm is mainly based on a single driving cycle, it is obvious that many factors might be often neglected by designer, such as different driving cycles would suit for different control strategies. But they tend to make decisions on the balance of torque distribution and battery power that based on a single driving cycle. Therefore, it is very difficult to achieve the optimal control in each case. In this paper we introduce a new design concept of Multi-operating mode energy management, a mathematical model of the energy management applied to a hybrid vehicle system is presented. Results of simulations using the model with the Multi-operating mode energy management were compared with results of simulations using a model with the single mode energy management, allowing the energy efficiency evaluation of the proposed energy management system.

The mechanical behavior of rubber-like materials is usually characterized by a strain energy density function, w. The parameters defining the density function, w, are considered as material parameters that need to be identified. Traditional experimental techniques, such as strain gauges, require numerous tests in homogeneous deformation modes and cut-out standard samples, to determine the appropriate strain energy form and parameters. In the present paper, the Finite Element (FE)-model updating based techniques is used to reduce the number of experimental tests for the identification of rubbery materials. In order to identity the analytical form of the strain energy, w, it is possible that we use only one single test of the component containing the rubber-like material. The example of an engine mount is used to illustrate the methodology.

Several details of the mechanism of gear lubrication are still in doubt in spite of many decades of study of this subject. The focus of our work is the investigation of the mechanism by which oil† temperature variations affect gear idle rattle, which requires an understanding of the distributions of lubricant and heat within a gearbox. This paper presents the findings of a study of lubricant flow in a simple model gearbox by means of CFD (Computational Fluid Dynamics) and its validation by a series of tests on a spur gear rig. The commercial CFD code Fluent is used to simulate the splash flow of lubricant, using the techniques of dynamic meshing and VOF (Volume of Fluid). Our model takes into account the effects on the distribution of gear lubricant of lubricant level and physical properties as well as rotational speed. The results demonstrate that the flow patterns are strongly influenced by all these variables.

Whole field displacement/strain measurement of automotive components can be done efficiently by digital image correlation based technique. Inverse problems with this kind of input data, such as the identification of damage parameters/effective modulus in different part of a component, can be pursued by either virtual fields method or finite element model updating. In this paper, the two methods are applied to the identification of a tension plate with a circular hole, and different aspects of the two methods are discussed. It is found that the success of virtual fields method relies on the choice of a set of optimal virtual displacement fields; finite element model updating, on the other hand, can be applied to any geometry and any load condition, and can also be applied to problems where only limited number of measurements are available. However, its performance relies on the choice of optimization algorithms.

The Noise, Vibration, Harshness (NVH) behavior is one of the predominant factors for market acceptance of vehicles. As to thin parts in the automobiles, the effect result of rib stiffening can significantly alter noise and vibration character of the plate. In this paper, the location and the dimensions of two cross stamped ribs in a plate have been optimized to minimize the radiated noise power under broad-band excitation. The objective of the study is to determine effective design methods for vibroacoustic optimization of the ribs in a plate. The reconstruction of the finite element model and the boundary model in the optimization iterations is one of key factors. Radiated sound power is calculated using a boundary element method, with a finite element solver ANSYS for the solution of the structural vibration.

The flow structure inside the catalytic converter of gasoline engines is very important for consideration of the catalyst light-off condition, converter durability and conversion efficiency. However, the available experimental data under actual engine exhaust conditions are quite limited due to its complicated configuration, critical operating conditions and difficult optical access. Therefore, an experimental study was performed, using laser Doppler velocimetry technique, to measure the velocity distributions inside two production dual-monolith catalytic converters fitted on a firing gasoline engine over several engine operating conditions. This paper reports the normal velocity characteristics measured in a plane 1 mm away from the front surface of first monolith. A small fraction of titanium (IV) isopropoxide was dissolved in gasoline for generating titanium dioxide seeding particles during the engine combustion.