# Study of Heat Distribution in Railway Switch Using Resistive Heater in Cold Climate Conditions
## 1 Introduction  
The parts of railroad tracks that allow trains to switch between tracks are known as railway switches, turnouts, or points. Based on their operational performance and safety, switches play a critical role in the network. However, ice and snow accumulation on these switches can impede their movement, leading to operational issues and safety concerns. To avoid these problems, the railway industry is using a variety of anti-icing and de-icing techniques. These methods include hot air blowers, chemicals, gas heating, water, and geothermal heating. Among railway switch heating methods, resistive electrical heaters are more common, especially in Europe [1; 2; 3; 4; 5; 6]. Such electrical heaters produce heat when the current passes through a resistive material. The primary component is a flat or oval-shaped resistive heater installed on the stock rail foot (Figure 1). The optimal location of the heater on the rail and the need for extra special equipment can vary depending on the kind of turnout and the environment [6]. Despite its simple design and ease of installation, resistive electrical heaters do not have high electrical and thermal efficiency. These heaters heat the entire rail and use significant electrical energy for the lengthy rail. Also, the heat radiates faster from the rail since it is larger than the heater and has a high volume in contact with the air temperature differential [7]. Over the years, it has been observed that resistive electrical systems are not capable of heating turnouts efficiently. Researchers have examined several design approaches for resistive heater performance improvement. Design changes have been made to the resistive heaters, which include: (1) expanding the contact area betweenthe heater and rail by converting the heating element's shape from cylindrical to flat; (2) modifying the outer sheath material of the heating element to make it resistant to most chemicals, water, and salt; (3) converting the embedded resistance wire's linear shape to a helical one; (4) utilization of insulating material to conceal the heating element on the air-facing surface [8]; and minimizing hot air loss by using covers, which can reduce energy costs and protect switches from harsh weather [9]. Induction heating for railway switches was first introduced and tested in Poland in the year 1978 for some selected switches. In this design, rails were heated with eddy currents induced inside the rails. Heating wires were insulated and were not in contact with the rails in a galvanic way. Through the years, this method has evolved, and researchers have performed several studies on this concept. In 2012, [PERSON] et al. reviewed this concept and developed a 3D simulation model. In this study, they analyzed the electric and magnetic characteristics of rails in the presence of induction heating using the Flux3D [1]. In 2021, another study was published, where researchers compared the melting time of an ice cube, the temperature of the rail, and energy consumption between induction heating at different frequencies and conductive heaters. The results showed that the induction system sends the heat to ice and snow directly, while in the conductive heater, a great amount of heat is stored in the stock rail, which increases the energy consumption of this method. Results did not show that induction heating was an absolutely better method than the conduction system. In some frequencies, it performed better in the melting time and energy consumption, so it is possible to find the optimal situation for induction heating, which can save up to 70% of energy compared to the resistive method [6]. In 2015, [PERSON] conducted a numerical study to compare resistive and inductive heating systems of railway switches. He simulated heat transfer and calculated respective heat losses. In this study, he did not consider phase transformation and melting.