Thermal imaging diagnostics in innovative railroad switch heating systems

The article discusses four different options for entering the guide wheels to the guard rail bends: when driving along a straight path of railroad switches with a straight or curved frog, the rolling stock has a free arrangement in a track; the flanges of its wheelsets either fall into the guard rail gutter without hitting the bends, or run into the bend at any point in it; when moving against the direction and along the direction when leaving the frog curve of the same direction with the railroad switch curve, the front axle of each bogie runs along the outer wheel flange onto the outer rail; the rear axle, depending on the insertion mode, is either pressed against the inner rail, or occupies an intermediate position, or pressed against the outer rail; in case of a directly movement from a straight path to a curved frog, the rolling stock is in a track in a free position and a impact is possible either in the working face of the core, or in the guard track bend; when directly entering the railroad switch with a curve, the reverse railroad switch impact with the front axles of the rolling stocks or bogies will occur in the check rails, the wheels of the rear axles can hit the bends of the guard rails. In all variants of the impact on the bends of guard rails when moving on the side track, they are determined by the number of strokes, the mass participating in the impact, the angle of impact, as well as the amount of transverse displacement of the rolling stock when hitting a guard rail, characterizing the work extinguished by the guard rail, and the smoothness of movement in the frog zone, methods calculating the determination of the length of the straight bends of the guard rails with straight frogs, determining the length of the rectilinear bends of the guard rails with curved frogs, determining the length of the curved bends to guard rails having a constant angle of inclination to the roadway with curvilinear frogs. Guard rails of the sideways of railroad switches take significantly greater impacts than guard rails of the forward direction. The only way to reduce the impact on these bends is to reduce the impact angles and collisions. For railroad switches with curved frogs, as well as for railroad switches with straight grogs with a railroad switch curve extending to the guard rails zone, it is best to use guard rails with curved bends that have the smallest length and provide the most secure entry to the bend.

A stochastic model-based approach to analyse reliable energy-saving rail road switch heating systems

Enhancing sustainability of the railway infrastructure: Trading energy saving and unavailability through efficient switch heating policies

When designing railroad switches for high speeds of movement, it is necessary to provide passengers with a comfortable ride when the train moves on a side track by limiting the values of the so-called centrifugal acceleration and increment (change) of centrifugal acceleration per unit time (second). If it is necessary to realize the movement speed of the railroad switch on the side track over 50 km/h, the main factor in determining the radius of the turnout curve according to the conditions of driving comfort is the limitation of the increment (change) value of centrifugal acceleration per unit time (second). Based on this, when designing railroad switches for high speeds of movement, it is advisable to use curves of variable radius as a turnout curve. Curves of variable curvature are considered: cubic parabola; fourth-degree parabola and a sinusoid, recommended as turnout curves, which are given a comparative assessment of the conditions for their use in railroad switches of flat grades. Of the considered curves of variable radius, the curve that varies according to the law of a sinusoid is the most suitable for use as a turnout curve in railroad switches of flat grades for high speeds of movement.

Life Cycle Cost of a Railroad Switch

Rail road switches enable trains to be guided from one track to another, and rail road switches heaters are used to avoid the formation of snow and ice during the cold season in order to guarantee their correct functioning. Managing the energy consumption of these devices is important in order to reduce the costs and minimise the environmental impact. While doing so, it is important to guarantee the reliability of the system.In this work we analyse reliability and energy consumption indicators for a system of (remotely controlled) rail road switch heaters by developing and solving stochastic models based on the Stochastic Activity Networks (SAN) formalism. An on-off policy is considered for heating the switches, with parametric thresholds representing the temperatures activating/deactivating the heating. Initial investigations are carried on to understand the impact of different thresholds on the indicators under analysis (probability of failure and energy consumption).KeywordsEnergy ConsumptionLearn AutomatonHybrid AutomatonLearn AutomatonInput GateThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Railway transport plays a special role in the transportation of oil and petroleum products. Ensuring the speed and reliability of transportation is one of the important issues. The role of railroad switch electric drives in solving this problem is great. Package type «AN» reducer have a number of advantages over traditional ones. The article presents the features and the essence of increasing the technological and exploitational parameters of the transmission mechanism of railroad switches with the help of a new innovative package type «AN» reducer, developed at AzTU. An analysis of the work of friction on plain bearings used in package reducers, instead of keyed connections in traditional gearboxes, is given. The effectiveness of the use of package type «AN» reducers in the transmission mechanisms of railroad switch electric drives has been revealed. Keywords: railroad switch drive; mechanism; innovative; increase; reducer; reliability.

Railway turnouts (railroad switches) are the weakest components of a rail track system. Cracks may occur in the railway turnouts due to cyclic loadings and impact loadings imposed by passing trains. It is of great significance to continuously monitor the health condition of the railway turnouts and promptly detect crack once it initiates. It is well-known that acoustic emission (AE) signals are generated when a crack initiates and propagates. Detecting the high-frequency AE signals by piezoelectric sensors can help identify the crack and its location. This paper reports the design and implementation of a PZT-based system for crack monitoring of railway turnouts. This online monitoring system is activated for signal collection by a trigger system when a train is arriving to pass through the instrumented railway turnout. It mainly detects the AE signals generated when a crack initiates during the train passage or when the initiated crack expands during the passage of a heavy haul wagon. This system has been installed on a railroad line for over one year and has successfully detected the damage occurring at a railroad switch during its service period. This paper also briefs a guided-wave-based system for monitoring of micro-cracks in rail tracks by integrating FBG and PZT sensors.

Synergistic development of heating system decarbonization transition and large-scale renewable energy penetration: A case study of Beijing

The on-spot consumption scheme of new energy can improve the utilization efficiency of energy and provide references for the transformation from the conventional regional coal heating mode to the more efficient electric heating mode. To figure out the economic benefit brought by the new energy heating mode, it’s necessary to evaluate its cost-benefit and construct reasonable model to study the dynamic market response. Therefore, this paper aims to evaluate the comprehensive cost benefit of the investment and operation of new energy heating (NEH) system and find ways to improve the said cost benefit. At first, this paper built an investment and operation model for the said NEH system, and constructed an objective function with the minimization of new energy disuse rate as the objective in the commissioned operation scheme for new energy on-spot consumption system connected with large electric heating boiler and large-capacity heat accumulator. Then, the paper gave the structure of the NEH system, and analyzed the main participants, investment and operation modes, and economic benefit of the NEH system. At last, corresponding experimental results and analysis results of an example case were given, which had verified the effectiveness of the proposed model.

The combined method of generating electric and heat energy at CHP plants has been and remains the most effective way of fuel saving both in housing and communal services and in industry. In Russia, historically, a qualitative method of regulation has been adopted, which consists in changing the temperature of the fluid depending on the change in the temperature of the outside air at a constant flow rate of the fluid. An analysis of the heat supply schemes of a number of Russian cities revealed that central quality regulation at heat sources has practically ceased everywhere. In modern methods of calculating the qualitative and quantitative regulation, the main load is heating, and the load of hot water is taken into account only by increasing the flow rate of network water and the variable modes of joint operation of heating and hot water systems are not calculated. Thus, at present, there are no methods for calculating the qualitative and quantitative regulation, allowing to fully taking into account the effect of the load of hot water on the operation of heating systems. Therefore, in modern conditions, the previously developed methods and technological methods of controlling the combined heat load are characterized by a decrease in efficiency, and, accordingly, the problem of their optimization arises. For different temperatures of outdoor air, the calculation of variable operating modes of the heat supply system was carried out, which showed that the existing schedules of qualitative and quantitative regulation cannot provide a comfortable temperature condition of the premises. Under the conditions of a connected supply of heat, simply adding up the flows of network water for heating and hot water supply fails to achieve optimal thermal conditions for the premises. Therefore, further improvement of the technology of the central qualitative and quantitative regulation of the heat load taking into account hot water supply is required.

“Transform coal heating to electric heating” is an important part of the electric power alternative strategy. The electric heating has an incomparable advantage over other heating systems, which makes it widely recognized. Using ground source heat pump for electric heating brings more social and economic benefits. On the basis of studying the method for calculating the thermal load of users and the principle of chance-constrained programming (CCP), the two-layer operational optimal model of ground source heat pump system is established, which aims to minimize electricity consumption and maximize the thermal comfort. The improved PSO algorithm is used to resolve the model to obtain the optimal control strategy of ground source heat pump system and the load distributive strategy of heat pump units. The analysis of examples-, a campus heating building heating system, shows that the model and the control strategy proposed in this paper can improve the energy efficiency of electric heating system on campus and lower the cost of electricity consumption without reducing the thermal comfort. This approach is instructive and referential for the operation of electric heating system on park buildings.

The study was devoted to solving the issue of creating new electric heating devices that can be used in autonomous heat supply systems. The issues were resolved by developing an original low-pressure electric steam heater. The study was aimed at improving the efficiency of heat supply systems for buildings and structures. Given the current trends in the global striving for energy conservation, it cannot be fully realized without the introduction of high-tech and low-energy-consuming electrical equipment. As a result of theoretical studies of a heat pipe with an electric heater, a design of an electrovacuum heating element has been developed. The low-pressure electric steam heater can be used in heat supply systems of autonomous users. Thermal energy transfer is currently accompanied by substantial energy losses since the heat carrier has to pass considerable distances. Switching of the facility to the heating plant is impossible in some cases because of technical problems or significant material costs for laying pipelines. As a result of the study, the dependence of heating the heat pipe at various volumes of the heat carrier and mass of the pipe itself was established. When a certain mass is reached, the temperature of the heating surfaces can reach 70 °C which is considered acceptable. The experimental data obtained have made it possible to develop an electric heater of new generation with a fundamentally new design of the heating element. It combines the efficiency of an electric spiral and comfortable warmth from a traditional radiator. This heater is an explosion and fire-safe and can be integrated into the Smart Home system

Norwegian households’ perception of wood pellet stove compared to air-to-air heat pump and electric heating

The aim of this study was to map the parameters that have the greatest impact on the environmental impact of heating systems usually used in Nordic single-family dwellings. The study focused on mapping the technical requirements for efficient operation of heating systems in a broader context. The results suggest that the ability of a heating system to be operated with a low-temperature water supply depends to a large extent on the heating demand of a building. It was shown that an increase in the water flow rate in hydronic circuits would significantly increase the thermal efficiency from analyzed heating systems. This increase would not increase the pumping power need, nor would it create noise problems in distribution network if the distribution pipes and thermostatic valves were properly selected. However, this increase in water flow rate improved the efficiency of considered closed-loop heat pump. It was further shown that the efficiency of the heat pump could be additionally improved by halving the energy needs for the domestic hot-water and circulators. The main conclusion from this study is that exergy usage, CO2 emission and thereby environmental impact are significantly lower for heating systems that are operated with small temperature drops.