Aerodynamic Loads Induced by Passing Trains on Track Side Objects

Author(s):  
Sabrina Rutschmann ◽  
Klaus Ehrenfried ◽  
Andreas Dillmann
Keyword(s):  
Author(s):  
Yu.Yu. Byalovskiy ◽  
I.S. Rakitina

Cortical mechanisms play an important role in breathing control under increased breathing resistance (resistive loads). Cortical mechanisms determine the level of voluntary motivation, which significantly affects the tolerance of resistive breathing loads. The purpose of the paper is to determine the effect of voluntary motivation on the tolerance of additional breathing resistance. Materials and Methods. The authors formed procedural motivation by means of moral encouragement or financial rewards of the subjects. Simulation of increased breathing resistance was performed using in-creasing values of thresholdless inspiratory aerodynamic loads: 40, 60, 70, and 80 % from the maximum intraoral pressure. Results. The maximum level of tolerance of additional breathing resistance was observed in volunteers with a material and subsidiary procedural motivation of activity. Under respiratory loads, these subjects demonstrated the greatest deviations of the functional state indicators. Undefined motivation based on the mobilization of goal-oriented resources with moral stimulation showed less efficiency. Lack of specially formed procedural motivation led to minimal tolerance of resistive loads. Conclusion. Procedural motivation, aimed at overcoming additional breathing resistance, significantly increases the tolerance of individual protective means of respiratory organs, which maintains health of workers in a polluted technological environment. Keywords: motivation, tolerance, increased breathing resistance. Большую роль в регуляции дыхания при увеличенном сопротивлении дыханию (резистивных нагрузках) играют кортикальные механизмы. Корковые механизмы определяют уровень произвольной мотивации, которая существенно влияет на переносимость резистивных дыхательных нагрузок. Цель исследования – определение влияния произвольной мотивации на переносимость дополнительного респираторного сопротивления. Материалы и методы. Процессуальную мотивацию формировали методом морального или материального поощрения испытуемых. Моделирование увеличенного сопротивления дыханию проводили с помощью предъявления возрастающих значений беспороговых инспираторных аэродинамических нагрузок: 40, 60, 70 и 80 % от максимального внутриротового давления. Результаты. Максимальный уровень переносимости дополнительного респираторного сопротивления наблюдался у добровольцев, у которых была сформирована материально-субсидивная процессуальная мотивация деятельности; у этой категории испытуемых во время действия дыхательных нагрузок отмечались наибольшие отклонения показателей функционального состояния. Произвольная мотивация на основе мобилизации волевых ресурсов при моральном стимулировании характеризовалась меньшей эффективностью, а отсутствие специально сформированной процессуальной мотивации сопровождалось минимальной переносимостью резистивных нагрузок. Выводы. Процессуальная мотивация, сформированная для преодоления дополнительного респираторного сопротивления, существенно повышает переносимость средств индивидуальной защиты органов дыхания, что имеет большое значение для сохранения здоровья работающих в условиях загрязненной производственной среды. Ключевые слова: мотивация, переносимость, увеличенное сопротивление дыханию.


2017 ◽  
Author(s):  
Narayanan Komerath ◽  
Nandeesh Hiremath ◽  
Dhwanil Shukla ◽  
Joseph Robinson ◽  
Ayush Jha ◽  
...  

AIAA Journal ◽  
2002 ◽  
Vol 40 (6) ◽  
pp. 1105-1112 ◽  
Author(s):  
Tianshu Liu ◽  
D. A. Barrows ◽  
A. W. Burner ◽  
R. D. Rhew

2015 ◽  
Vol 764-765 ◽  
pp. 740-746
Author(s):  
Hang Yuan ◽  
Chen Lu ◽  
Ze Tao Xiong ◽  
Hong Mei Liu

Fault detection for aileron actuators mainly involves the enhancement of reliability and fault tolerant capability. Considering the complexity of the working conditions of aileron actuators, a fault detection method for an aileron actuator under variable conditions is proposed in this study. A bi-step neural network is utilized for fault detection. The first neural network, which is employed as the observer, is established to monitor the aileron actuator and generate the residual error. The other neural network generates the corresponding adaptive threshold synchronously. Faults are detected by comparing the residual error and the threshold. In considering of the variable conditions, aerodynamic loads are introduced to the bi-step neural network. The training order spectrums are designed. Finally, the effectiveness of the proposed scheme is demonstrated by a simulation model with different faults.


Author(s):  
Ankit Raj ◽  
K Anandhanarayanan ◽  
R Krishnamurthy ◽  
Debasis Chakraborty

Fairings are provided to cover hypersonic air breathing vehicle to protect it from adverse aerodynamic loading and kinetic heating. Separation dynamics of fairings is an important event in the launch of vehicle. Extensive computational fluid dynamics simulations are carried out for the design of fairings and vehicle and selection of time sequences of various separation events. A ground test of fairing separation is conducted in the sled facility to check the structural integrity and functionality of various separation mechanisms and flight hardware. Simulations have been carried out to study the separation dynamics of fairings at test conditions using grid-free Euler solver to get the aerodynamic loads and the loads are integrated to get the trajectory of fairings. The aerodynamic loads are provided to verify the structural integrity of various components and the trajectory of panels is used in the test planning. The pressure distributions on the vehicle are compared with the test results.


Author(s):  
Armando Alexandre ◽  
Raffaello Antonutti ◽  
Theo Gentils ◽  
Laurent Mutricy ◽  
Pierre Weyne

Abstract Floating wind is now entering a commercial-stage, and there are a significant number of commercial projects in countries like France, Japan, UK and Portugal. A floating wind project is complex and has many interdependencies and interfaces. During all stages of the project several participants are expected to use a numerical model of the whole system and not only the part the participant has to design. Examples of this are the mooring and floater designer requiring a coupled model of the whole system including also the wind turbine, the operations team requiring a model of the system to plan towing and operations. All these stakeholders require a coupled model where the hydrodynamics, aerodynamics and structural physics of the system are captured with different levels of accuracy. In this paper, we will concentrate on a simplified model for the aerodynamic loading of the turbine in idling and standstill conditions that can be easily implemented in a simulation tool used for floater, mooring and marine operations studies. The method consists of using a subset of simulations at constant wind speed (ideally close to the wind speed required for the simulations) run on a detailed turbine model on a rigid tower and fixed foundation — normally run by the turbine designer. A proxy to the aerodynamic loads on the rotor and nacelle (RNA) is to take the horizontal yaw bearing loads. The process is then repeated for a range of nacelle yaw misalignments (for example every 15° for 360°). A look-up table with the horizontal yaw bearing load for the range of wind-rotor misalignments investigated is created. The simplified model of the aerodynamic loads on the RNA consists of a fixed blade (or wing) segment located at the hub, where aerodynamic drag and lift coefficients can be specified. Using the look-up tables created using the detailed turbine model, drag and lift coefficients are estimated as a function of the angle between the rotor and the wind direction. This representation of the aerodynamic loading on the RNA was then verified against full-field turbulent wind simulations in fixed and floating conditions using a multi-megawatt commercial turbine. The results for the parameters concerning the floater, mooring and marine operations design were monitored (e.g. tower bottom loads, offsets, pitch, mooring tensions) for extreme conditions and the errors introduced by this simplified rotor are generally lower than 4%. This illustrates that this simplified representation of the turbine can be used by the various parties of the project during the early stages of the design, particularly when knowing the loading within the RNA and on higher sections of the tower is not important.


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