scholarly journals Innovative doubly-fed freight electric locomotive 2EV120 “Knyaz’ Vladimir”

2018 ◽  
Vol 239 ◽  
pp. 01001
Author(s):  
Kirill Domanov

The paper considers a new doubly-fed freight electric locomotive taking into account the world experience of locomotive construction, the regulatory base and operating conditions on the railways of Russia. Its parameters are presented: the main technical characteristics in comparison with currently used electric locomotives of new series, standard traction characteristics, and the characteristic of electric braking. Features of the design of the units and parts of the undercarriage and brake equipment are given. The studied doubly-fed freight electric locomotive is designed taking into account the optimal combination of equipment backup capabilities and increased operational reliability with minimization of the failure flow causing the withdrawal of two or more traction axles due to the faults. It has promising possibilities for replacing outdated locomotives with alternating and direct current, operated on sections with changing and adjacent stations, electrified on a constant and single-phase alternating current in the places where such sections are joined to the extent of the organization of traffic control according to the principles of working domain technologies. In this case, the joints between the two types of the train current can pass nearly without stopping, their running time is shortened, and the performance indicators are improved.

2021 ◽  
Vol 21 (3) ◽  
pp. 106-114
Author(s):  
P.A. Emelyanov ◽  

Today, automobile and tractor trains with trailers are quite popular vehicles used for transporting agricultural goods in the agro-industrial complex of the Russian Federation. Road trains and trac-tors with trailers are characterized by lower performance indicators (maneuverability, stability of movement) than single vehicles. Accordingly, special requirements for safety and trouble-free op-eration are imposed on motor-tractor trains. The author of the article proposes a technical solution that provides longitudinal stability of the movement of multi-link trackless vehicles, and has, in comparison with known analogues, simplicity of design and increased efficiency in the operating conditions of multi-link tractor trains. Analytical studies have been carried out, which made it possible to justify the rational kinematic and geometric parameters of the proposed technical solu-tion. The strength parameters of the damping device installed at the coupling point of tractors and trailers, and ensuring the operational reliability of trailed dump vehicles, are determined. The re-sults of the conducted research are recommended to both domestic and foreign research institutes, design and production structures of the automotive industry for further study and refinement of the proposed device with a view to its possible introduction into practice.


1961 ◽  
Vol 65 (606) ◽  
pp. 403-407
Author(s):  
J. L. Anast

The application of automatic data processing techniques to air traffic control has been espoused by both operational and research and development groups dealing in air traffic control throughout the world. As far back as 1947, in the U.S.A., the Special Study Group, SC-31 of the Radio Technical Commission for Aeronautics suggested that a high degree of automation be applied—including rigid control of all flights and their times of arrival.


2020 ◽  
Author(s):  
Pieter-Jan Daems ◽  
Y. Guo ◽  
S. Sheng ◽  
C. Peeters ◽  
P. Guillaume ◽  
...  

Abstract Wind energy is one of the largest sources of renewable energy in the world. To further reduce the operations and maintenance (O&M) costs of wind farms, it is essential to be able to accurately pinpoint the root causes of different failure modes of interest. An example of such a failure mode that is not yet fully understood is white etching cracks (WEC). This can cause the bearing lifetime to be reduced to 5–10% of its design value. Multiple hypotheses are available in literature concerning its cause. To be able to validate or disprove these hypotheses, it is essential to have historic high-frequency measurement data (e.g., load and vibration levels) available. In time, this will allow linking to the history of the turbine operating data with failure data. This paper discusses the dynamic loading on the turbine during certain events (e.g., emergency stops, run-ups, and during normal operating conditions). By combining the number of specific events that each turbine has seen with the severity of each event, it becomes possible to assess which turbines are most likely to show signs of damage.


Buildings ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 37
Author(s):  
Zhiwen Xiao ◽  
Yong Qin ◽  
Zeshui Xu ◽  
Jurgita Antucheviciene ◽  
Edmundas Kazimieras Zavadskas

The journal Buildings was launched in 2011 and is dedicated to promoting advancements in building science, building engineering and architecture. Motivated by its 10th anniversary in 2021, this study aims to develop a bibliometric analysis of the publications of the journal between April 2011 and October 2021. This work analyzes bibliometric performance indicators, such as publication and citation structures, the most cited articles and the leading authors, institutions and countries/regions. Science mappings based on indicators such as the most commonly used keywords, citation and co-citation, and collaboration are also developed for further analysis. In doing so, the work uses the Scopus database to collect data and Bibliometrix to conduct the research. The results show the strong growth of Buildings over time and that researchers from all over the world are attracted by the journal.


2021 ◽  
Author(s):  
Edwin Kipchirchir ◽  
Manh Hung Do ◽  
Jackson Githu Njiri ◽  
Dirk Söffker

Abstract. Variability of wind profiles in both space and time is responsible for fatigue loading in wind turbine components. Advanced control methods for mitigating structural loading in these components have been proposed in previous works. These also incorporate other objectives like speed and power regulation for above-rated wind speed operation. In recent years, lifetime control and extension strategies have been proposed to guaranty power supply and operational reliability of wind turbines. These control strategies typically rely on a fatigue load evaluation criteria to determine the consumed lifetime of these components, subsequently varying the control set-point to guaranty a desired lifetime of the components. Most of these methods focus on controlling the lifetime of specific structural components of a wind turbine, typically the rotor blade or tower. Additionally, controllers are often designed to be valid about specific operating points, hence exhibit deteriorating performance in varying operating conditions. Therefore, they are not able to guaranty a desired lifetime in varying wind conditions. In this paper an adaptive lifetime control strategy is proposed for controlled ageing of rotor blades to guaranty a desired lifetime, while considering damage accumulation level in the tower. The method relies on an online structural health monitoring system to vary the lifetime controller gains based on a State of Health (SoH) measure by considering the desired lifetime at every time-step. For demonstration, a 1.5 MW National Renewable Energy Laboratory (NREL) reference wind turbine is used. The proposed adaptive lifetime controller regulates structural loading in the rotor blades to guaranty a predefined damage level at the desired lifetime without sacrificing on the speed regulation performance of the wind turbine. Additionally, significant reduction in the tower fatigue damage is observed.


2020 ◽  
Author(s):  
Paulo Andrade Souza ◽  
Renan R. dos Santos ◽  
Manoelito C. N. Filho ◽  
Daniel Barbosa ◽  
Luciano Sales Barros

Due to the increasing penetration of Renewable Energy Sources (RES) such as wind energy in electrical grids, Wind Energy Conversion Systems (WECS) participation in primary control is becoming required including the Doubly Fed Induction Generator (DFIG)-based WECS. High integration of large scale DFIG-based WECS brings new challenges to their primary control support, and more strongly due to the wind condition and grid parameter uncertainties. One of the most used types of control strategy for DFIG-based WECS primary support is the synthetic inertia, however, robustness of these techniques have not been tested. In this work three synthetic inertia control strategies will be tested under different operating conditions of wind speed, frequency and voltage sag. For testing the DFIG-based WECS, it was modeled on ATP including its control systems and the results quantified the controllers robustness on the tested controllers with respect to transient frequency behavior.


2021 ◽  
Vol 345 ◽  
pp. 00027
Author(s):  
Václav Sláma ◽  
David Šimurda ◽  
Lukáš Mrózek ◽  
Ladislav Tajč ◽  
Jindřich Hála ◽  
...  

Characteristics of a new compact valve design for steam turbines are analysed by measuring pressure losses and oscillations on the valve model. It is the model of an intercept valve of the intermediate-pressure turbine part. This valve is relatively smaller hence cheaper than usual control and intercept valves. Besides, four different valve seat angles were tested in order to investigate the valve seat angle influence. In order to further clarify measured phenomena, the wide range of numerical simulations were also carried out. Measurements were performed in the Aerodynamic laboratory of the Institute of Thermomechanics of the Czech Academy of Sciences in an air test rig installed in a modular aerodynamic tunnel. Numerical simulations were performed in the Doosan Skoda Power Company using a package of ANSYS software tools. Measurement results are compared with numerical and generalized in the form of valve characteristics and pressure oscillation maps. As a result of the pressure loss analysis, pressure losses in similar valve assemblies can be predicted with required accuracy for each new turbine where modern compact valves are used. As a result of the pressure oscillation analysis, operating conditions at which dangerous flow instabilities can occur were identified. Thanks to this, the areas of safe and dangerous operating conditions can be predicted so that the operational reliability of the valve can be guaranteed.


2013 ◽  
Vol 11 (1) ◽  
pp. 225-242 ◽  
Author(s):  
Chunxi Lu ◽  
Yongmin Zhang ◽  
Mingxian Shi

Abstract Fluid catalytic cracking (FCC) is a dominant refining conversion process in China’s most refineries. After decades of development, China has already become one of the major FCC technology licensors in the world. In this review, the research and development (R&D) activities on FCC riser termination device (RTD) technologies in China are reviewed and discussed. Emphasis is put on the R&D of a series of advanced RTD technologies led by China University of Petroleum, Beijing, which initiated in the early 1990s when more and more China’s FCC units chose to process more residue feedstock. Followed by the guideline of three “quick”s and two “high”s, two early types of RTD systems with coupled zones for gas–solids centrifugal separation and pre-stripping were developed and applied successfully in commercial units. Significantly reduced yields of coke and dry gas due to restrained post-riser reactions and satisfactory particle recovery efficiency were achieved. These were the fender-stripper cyclone and vortex quick separator systems designed for external- and internal-riser FCC units, respectively. Later, further improvement efforts led to the development of another two RTD systems, i.e. the circulating-stripper cyclone system for external-riser units and super vortex quick separator system for internal-riser units. By now, nearly 50 applications were commissioned with a sum FCC capacity of 40.0 Mton/a, nearly one-third of China’s total FCC processing capacity. Besides, other research efforts, such as the geometry optimization efforts on LD2 type separator, the studies on RTD for down-flow riser FCC units, and the idea of non-disengager FCC unit are also discussed in this review. To accommodate to degraded feedstock, more stringent environmental regulations and new FCC process technologies, future R&D efforts on RTD technologies should be put on improvements to further satisfy the three-“quick”s and two-“high”s requirements with changing FCC operating conditions and different process requirements.


2018 ◽  
Vol 140 (2) ◽  
Author(s):  
Chirag R. Kharangate ◽  
Ki Wook Jung ◽  
Sangwoo Jung ◽  
Daeyoung Kong ◽  
Joseph Schaadt ◽  
...  

Three-dimensional (3D) stacked integrated circuit (IC) chips offer significant performance improvement, but offer important challenges for thermal management including, for the case of microfluidic cooling, constraints on channel dimensions, and pressure drop. Here, we investigate heat transfer and pressure drop characteristics of a microfluidic cooling device with staggered pin-fin array arrangement with dimensions as follows: diameter D = 46.5 μm; spacing, S ∼ 100 μm; and height, H ∼ 110 μm. Deionized single-phase water with mass flow rates of m˙ = 15.1–64.1 g/min was used as the working fluid, corresponding to values of Re (based on pin fin diameter) from 23 to 135, where heat fluxes up to 141 W/cm2 are removed. The measurements yield local Nusselt numbers that vary little along the heated channel length and values for both the Nu and the friction factor do not agree well with most data for pin fin geometries in the literature. Two new correlations for the average Nusselt number (∼Re1.04) and Fanning friction factor (∼Re−0.52) are proposed that capture the heat transfer and pressure drop behavior for the geometric and operating conditions tested in this study with mean absolute error (MAE) of 4.9% and 1.7%, respectively. The work shows that a more comprehensive investigation is required on thermofluidic characterization of pin fin arrays with channel heights Hf < 150 μm and fin spacing S = 50–500 μm, respectively, with the Reynolds number, Re < 300.


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