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In recent times, there has been an increased demand for electric vehicles. In this context, the energy management of the electric motor, which are an important constituent of electric vehicles, plays a pivotal role. A lot of research has been conducted on the optimization of heat flow through electric motors, thus reducing the wastage of energy via heat. Futuristic power sources may increasingly rely on cutting-edge innovations like energy harvesting and self-powered induction motors. In this context, effective thermal management techniques are discussed in this paper. Importance was given to the potential energy losses, hotspots, the influence of overheating on the motor efficiency, different cooling strategies, certain experimental approaches, and power control techniques. Two types of thermal analysis computation methods, namely the lumped-parameter circuit method (LPCM) and the finite element method (FEM), are discussed. Also, this paper reviews different cooling strategies. The experimental research showed that the efficiency was greater by 11% with the copper rotor compared to the aluminum rotor. Each rotor type was reviewed based on the temperature rise and efficiency at higher temperatures. The water-cooling method reduced the working temperatures by 39.49% at the end windings, 41.67% at the side windings, and by a huge margin of 56.95% at the yoke of the induction motor compared to the air-cooling method; hence, the water-cooling method is better. Lastly, modern cooling strategies are proposed to provide an effective thermal management solution for squirrel-cage induction motors.

One of the main energy sources utilized to produce power is coal. Due to the lack of combustion enhancement, the main issue with coal-based power plants is that they produce significant amount of pollutants. The major problem of slagging formation within the boiler; it sticks to the water tube walls, superheater, and reheater. Slagging might decrease the heat transferred from the combustion area to the water or steam inside the tubes, increasing the amount of coal and extra air. The abrupt fall of slag on the tube surface into the water-filled seal-trough at the bottom of the furnace might occasionally cause boiler explosions. In order to maximize heat transmission to the water and steam tubes by reducing or eliminating slag formation on the tube surface, the work presented here proposes an appropriate computational fluid dynamics (CFD) technique with a genetic algorithm (GA) integrated with conventional supercritical power plant operation. Coal usage and surplus air demand are both decreased concurrently. By controlling the velocity and temperatures of primary air and secondary air, the devised technique could optimize the flue gas temperature within the furnace to prevent ash from melting and clinging to the water and steam tube surfaces. Heat transmission in the furnace increased from 5945.876 W/m2 to 87,513.9 W/m2 as a result of the regulated slag accumulation. In addition to reducing CO2 emissions by 8.55 tonnes per hour and saving close to nine tonnes of coal per hour, the boiler’s efficiency increased from 82.397% to 85.104%.

Induction motors have gained a renewed interest due to this new shift from conventional power sources to electric power. These motors are known for their high commencing torque, adequate speed control and reasonable overload capacity. However, induction motors have an innate thermal issue wherein their lifespan and performance are strongly temperature dependent. Hence, it is highly essential to focus on the thermal management aspect of these motors to ensure reliability and enhance performance. Thus, the major purpose of the paper is to comprehensively review various approaches and methods for thermal analysis, including finite element analysis, lumped parameter thermal network and computational fluid dynamics tools. Moreover, it also presents various cooling strategies commonly adopted in induction motors. Furthermore, this study also suggests an integrated approach with two or more cooling strategies to be the need of the hour. These will combine the benefits of the individual system while helping to counter their drawbacks. This study will help to serve members of the scientific community, manufacturers or motors users who are interested in the thermal management of induction motors.

Nowadays, air conditioning consumes, on average, around one-fifth of the total power used in buildings globally. The present paper aims to provide the present status on the employment of Earth-to-Air Heat eXchangers (EAHX) to contain the consumption of energy and to reduce the effect on the environment in response to the Montreal and Kyoto protocols in a way to achieve cleaner energy production with a low Global Warming Potential (GWP) and a low ozone depletion potential (ODP). Different peculiarities and applications (direct or hybrid) are critically analyzed and reviewed. Specifically, in this paper, the different hybrid applications presented in the literature, where the Earth-to-Air Heat eXchangers are coupled to advanced systems, are reviewed. Finally, an IoT-based EAHX control system plan is reported and discussed to optimize energy efficiency and thermal comfort to suit operating conditions under different time zones.

Electric motors are utilitarian devices of great potential as they can limit the amount of pollution by drastically reducing the release of harmful gases. The implementation of the right type of advanced materials plays a vital role in the amelioration of modern automobiles while maintaining and/or improving the performance and efficiency of the electric motor. The use of lightweight materials could result in a better-performing vehicle that can be much less heavy. The replacement of regular cast iron, steel, and aluminum with lightweight materials such as fiber-reinforced polymer, carbon fiber, and polymer composites can reduce the weight of the motor without impacting its performance and improve its energy-saving capacity. This paper explores a way to reduce motor weight by employing a PA6GF30 30% glass fiber-reinforced polymer casing to reduce the weight of the motor while making cooling system modifications. This material was applied to the motor casing, which resulted in a significant reduction in weight compared to the water-cooled electric motor of aluminum (Alloy 195 cast) casing.

In the frame of the circular economy, welding of Ni-based superalloys has gained increasing importance when applied, for instance, to repairing highly expensive components widely used in strategical sectors, such as the defense and aerospace industries. However, correct process parameters avoiding metallurgical defects and premature failures need to be known. To reach this goal, Inconel 625 butt-welded joints were produced by CO2 laser beam welding and different combinations of process parameters. The experimental investigation was carried out with three parameters in two levels with an L4 orthogonal array. Laser power, welding speed, and shielding gas flow rate were varied, and the results were reported in terms of mechanical properties, such as microhardness, tensile strength, distortion, residual stress, and weld bead geometry, and metallurgy. At a lower welding speed of 1 m/min, the full penetration was observed for 3.0 kW and 3.3 kW laser powers. However, sound welds (porosity-free) were produced with a laser power of 3.3 kW. Overall, the obtained full-penetration specimens showed a tensile strength comparable with that of the parent material with residual stresses and distortions increasing with the increase in heat input.

This paper gives a comprehensive review of advanced cooling schemes and their applications to the permanent magnet synchronous motors (PMSMs), as well as investigating the electrical motor’s topologies its thermal design issues, materials and performances. Particularly, the electromagnetic and electric performances, machine sizing, together with the structural design, are given. In addition, the work addresses the motor’s material design and properties along with its insulation performance, which is the main goal of optimization. Mainly, thermal mapping with analysis is provided according to the different cooling methods, including air-cooling, water-cooling, oil-cooling, heat-pipe-cooling, potting silicon gelatin cooling, and as well as cooling strategies for tubes and microchannels. The most common special features and demands of the PMSMs are described in the appearance of the motor’s failures caused by uncontrolled temperature rise. In addition, heat sources and energy losses, including copper loss, core loss versus motor speed, and output power, are analyzed. The review of the proposed cooling methods that will achieve the required heat transfer of the PMSM is presented with numerical simulations and measurements data. A review of numerical methods and results, including the finite element methods (FEM), such as the Ansys CFD software, to obtain a high-accuracy thermal mapping model of the PMSM system is given. The revived methods and design requirements due to PMSM temperature profile and cooling flow at different rotor speeds and torque loads are investigated. Finally, the motor design recommendations, including the newly developed cooling solutions, which enable it to effectively redistribute the temperature and heat transfer, increasing the efficiency of the PMSM machine, are laid out.