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Energy efficiency analysis of railway turnout heating system with a melting snow model heated by classic and contactless heating method

Flis Mateusz

Archives of Electrical Engineering

2019

Vol. 68, nr 3

511--520

Maintaining railway turnout operability is crucial for ensuring railway transport safety. Electric heating of railway turnouts is a significant technical and economic issue. The classical heating is characterised by high power consumption. For this reason, research is needed to optimise the current system. This paper presents results of a numerical analysis and of experimental researches. The numerical analysis was carried out using the ANSYS software. There was conducted a numerical comparative analysis of energy loss during heating performed using two different heaters. Including the classical method and a heater thermally insulated from a rail. In the first step, heating of a working space filled with a substitute snow model was considered. The snow-covered surface area was held within the working space of the turnout. It was assumed that the snow substitute material had thermal properties approximately the same as real light snow. It was also assumed that the material is in the solid state which would not undergo a phase change. In the next step, a real snow model that included the phase change process was taken into account. The energy efficiency and heat distribution in the turnout have been analysed and compared. The experimental researches were carried out in a physical model. The results showed that the use of a contactless heater results in creating a larger area over which emitted heat affected snow in the working space. Consequently, more snow was melted around the contactless heater than the classic one. This experimental observation supported the results of the numerical analyses presented previously.

Transient analysis of alloy freezing in finite media with energy generation and convective cooling

Kumar S., Katiyar V. K.

International Journal of Applied Mechanics and Engineering

2010

Vol. 15, no 4

1155-1168

The effects of volumetric energy generation on phase change problems are important for many engineering applications including casting of nuclear waste materials, vivo freezing of biological tissues solar collectors etc. In the present study, a 1-D transient heat transfer analysis is carried out to study the effect of volumetric heat generation on alloy solidification in finite media with convective cooling. Enthalpy method is used to solve the mathematical model. The temperature profile and the motion of freezing interface are calculated for different values of volumetric heat generation and convective cooling. It is found that the motion of freezing interface slows down with an increase in the heat generation rate and for large values of heat generation it is not possible to solidify the whole region. The freezing accelerates with respect to an increasing rate of convective cooling. Further, for large values of heat generation the whole region can solidify by increasing convective cooling.