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To achieve a typical operating mode selection scheme, this paper conducts research on an adaptive cycle engine with fan on blade (FLADE). Based on the principles of aerodynamic thermodynamics of each component, a complete machine calculation model for this configuration with triple bypass mode is established on the MATLAB/Simulink platform. On the basis of this model, the performance of this configuration under different typical operating conditions of two working modes during the throttling process is analyzed by reducing iterative and residual variables. The simulation results show that under ground operating conditions, the triple bypass mode has higher thrust at low speed compared with the single-add-third bypass mode, while at high speed it is the opposite. The single-add-third bypass mode can be used for take off under high-power ground conditions, and for subsonic cruise conditions with low thrust requirements, the mode selection valve (MSV) can be activated to operate the engine in triple bypass mode after the aircraft climbs during the phase. [ABSTRACT FROM AUTHOR]

In order to study the evolution of aircraft wake vortices more deeply and precisely, and to ensure the safe operation of aircraft, the dissipation law of A330‑300 aircraft wake at different temperature vertical decreasing rates is studied in this paper by numerical simulation. The shear stress transport (SST) k‑ω turbulence model is chosen for the numerical simulation. The temperature field under five different temperature vertical decreasing rates is constructed, and the A330‑300 aircraft wake flow field is compiled within the temperature field to realize the calculation under different temperature vertical decreasing rates. The reliability of the numerical simulation method is verified by comparing the numerical simulation results with the radar detection data. The results show that for general turbulence intensities, different rates of vertical decreases in temperature act mainly on the decay phase of the wake, affecting the evolution of the wake by changing the temperature inside and outside the wake.The smaller the temperature vertical decreasing rate is, the larger the rate of decrease of circulation in the wake vortex decay region is. The larger the vertical rate of temperature decreases, the larger the rate of tail vortex sinking is and the larger the distance between vortex cores after rapid dissipations is. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of Nanjing University of Aeronautics & Astronautics is the property of Editorial Department of Journal of Nanjing University of Aeronautics & Astronautics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The thermal environment of maneuvering rudder shaft is a local problem to be considered in the design of thermal protection system of hypersonic missile. The flow structure in rudder shaft gap is complex， and under typical flight conditions， the peak of the local thermal environment of the rudder shaft is more serious than that of in large area. Aiming at the problem of thermal environment of hypersonic maneuvering warhead shaft， combined with numerical calculation and wind tunnel test， the variation of thermal environment of rudder shaft with attack angle， rudder deflection angle and Mach number is studied. Then， a four-parameter interpolation fitting method suitable for predicting the peak heat flow of rudder shaft is established. The results show that， for the rudder like letter“ + ”，the thermal environment of horizontal rudder shaft is the most severe； under the condition of small attack angle， the dimensionless heat flow of the rudder shaft increases gradually with the increase of the rudder deflection angle and Mach number， but under the condition of large attack angle， the influence of Mach number and rudder deflection on the dimensionless heat flow of the rudder shaft is small. The four-parameter fitting method established in this paper can be used to rapidly evaluate the peak thermal environment of the rudder shaft along the trajectory. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Data Acquisition & Processing / Shu Ju Cai Ji Yu Chu Li is the property of Editorial Department of Journal of Nanjing University of Aeronautics & Astronautics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, numerical simulation is used to analyze the effect of the trailing edge of the stationary blade sawtooth on the 3.5-stage compressor, and the influences of shape and positions of the sawtooth on the compressor speed. The results show that the full blade with high opening on the trailing edge of the inlet guide blade can broaden the stable range of the compressor at 90% speed, and barely impact the pressure ratio and efficiency. But it has little effect the compressor at 100% speed. In this study, a sawtooth with a small tooth width is better than that with a large tooth width, and a sawtooth with full high-opening blades is better than that with partial opening tip. This study deepens the understanding of the effect of serrated trailing edge blades on compressor performance, and provides a reference for research on improving compressor stability. [ABSTRACT FROM AUTHOR]

To solve the problem of computation termination， low computational precision and efficiency caused by mesh distortion during simulation, this paper conducts the secondary development of the ABAQUS software through python. A two-dimensional local mesh dynamic refinement algorithm is proposed. The development of the whole algorithm program is completed by studying the algorithm of the mesh refinement criterion and refinement method and the transfer process in the physics field. The algorithm is applied to two¬dimensional cutting simulation to realize dynamic refinement of local mesh. Compared with the model of global encrypted mesh，the computational efficiency of local mesh dynamic refinement is improved by 210% when the simulation accuracy error is within 5%. Finally， the accuracy of the two-dimensional cutting simulation model established by the algorithm is verified by experiments. The simulation results are basically consistent with the experimental results. [ABSTRACT FROM AUTHOR]

In recent years，the rapid development of aerospace industry has put forward an urgent demand for high efficiency and low cost manufacturing of large and high-performance advanced resin matrix composites. Resin transfer molding (RTM) is a technology for manufacturing advanced fiber reinforced resin matrix com¬posites. Compared with the existing hot-pressing technology，RTM has the advantages of simple equipment structure， high production efficiency and low manufacturing cost. In this paper， the research and application status of two typical RTM processes-Vacuum assisted-Resin transfer molding (VA-RTM ) and Light-Resin transfer molding (L-RTM) are reviewed. The existing problems of these two processes in manufacturing large high performance components are pointed out. The research status and technical difficulties of multi-field coupled numerical simulation， new simulation methods and multi-function simulation of RTM process are summarized. Based on above conclusions, the development trend for RTM process is discussed, which is ben¬eficial to provide reference for realizing rapid process optimization and obtaining high efficiency，high perfor¬mance and large components in RTM process. [ABSTRACT FROM AUTHOR]

In order to obtain the properties of anti-icing on the blowing rotating spinner, this paper analyzes the anti-icing principles and effects of the blowing rotating spinner in three aspects of air flow, impaction of water droplets and icing properties, using three-dimensional numerical simulation technology. Meanwhile, the experimental research is carried out using icing wind tunnel. The anti-icing conditions are analyzed from both of the icing thickness and range on the spinner surface, and the anti-icing effects of the blowing rotating spinner are validated in the icing environment. Above analysis shows that the anti-icing structure of the blowing rotating spinner has an excellent effect on anti-icing. [ABSTRACT FROM AUTHOR]