This comprehensive review critically examines recent research concerning the application of nanofluids in heat exchangers. The utilization of nanofluids, which are colloidal suspensions of nanoparticles in a base fluid, has garnered significant attention in enhancing heat transfer performance. Various studies have explored the potential benefits and challenges associated with incorporating nanofluids into heat exchanger systems. Through a systematic analysis of recent literature, this review assesses the effectiveness of nanofluids in improving heat transfer efficiency and overall performance of heat exchangers. Key parameters such as nanoparticle concentration, size, and type are thoroughly evaluated to understand their influence on heat transfer characteristics. Additionally, factors such as stability, flow behavior, and thermal conductivity enhancement are scrutinized to provide a comprehensive understanding of nanofluid behavior in heat exchangers. The review also addresses potential limitations and areas requiring further investigation to optimize the utilization of nanofluids in heat exchanger applications. By synthesizing recent findings, this review aims to contribute to the advancement of knowledge in the field of heat exchanger technology and nanofluid applications. Ultimately, the insights provided in this review offer valuable guidance for researchers and engineers seeking to enhance heat transfer processes through the implementation of nanofluid-based heat exchangers. Nanofluids offer advantages like enhanced thermal conductivity and tailored properties, promising optimized heat exchanger designs, leading to energy efficiency and reduced costs. However, challenges remain, such as nanoparticle dispersion and cost-effectiveness, necessitating further research for refinement. Interdisciplinary collaboration is crucial for advancing nanofluid applications, fostering innovation to meet demands for sustainable heat transfer solutions.

This paper investigates heat transfer in a horizontally oriented tubular heat exchanger through a comprehensive examination of both numerical simulations and experimental analyses. The primary focus is on copper as the material of interest, specifically examining an inner tube with a 14 mm internal diameter and 1 mm thickness, as well as an outer tube with a 29 mm external diameter and 1 mm thickness. In addition to these components, two perforated pipes with internal diameters of 11 mm and 20 mm are incorporated; contributing to an overall length of the heat exchanger measuring 281 mm. Notably, the perforation pipe features a 5 mm diameter hole on its periphery. A comprehensive assessment was conducted to appraise heat transfer and coefficients within a straightforward tubular heat exchanger. The mass flow rate of chilled water in the annular space fluctuated between 0.01 kg/sec and 0.11 kg/sec, while the steady flow rate of hot water within the inner tube remained constant at 0.11 kg/sec. Inlet temperatures for the hot water were established at 55 °C, 75 °C, and 85 °C, with the cold water maintaining a consistent inlet temperature of 29 °C throughout the experiment.

In this research, numerical modelling is used to explore the heat transfer through natural convection capabilities of nine aluminum integrated circuit chips that are installed on substrate board. The goal is to figure out where on the substrate board these IC chips would be best placed if they were arranged differently. The dimensionless parameter (λ) plays a very essential role, and by applying a hybrid technique consisting of ANN and GA. ANSYS Icepack calculates IC chip temperature distributions in 3D steady state numerical simulations. It has been shown that the form, dimensions, and IC chips' substrate board positioning affects their operating temperature. In comparison to the strategies that have been used in the past, hybrid optimization is the strategy that has shown to be the most reliable in properly predicting how the IC chips would be arranged on the substrate board. It has been observed that higher values of one of these parameters lead to a reduction in the maximum temperature surplus. A correlation has been established to illustrate this relationship as it increases. The most favorable simulation outcomes are utilized to drive a genetic algorithm (GA), which identifies the optimal configuration ensuring that the temperatures of the heat sources remain well below their specified maximum operating conditions, as outlined in the data sheets. The maximum temperature variation between the lowest and highest extreme configurations ranges between 4 - 8%. The smallest size IC chip, U2 with high heat dissipation rate attains the maximum temperature in the configuration, however, the temperature variation for the low powered IC chips U3, U4 and U7 are very small. Found good agreement of both the data with an error band of 10%, and thus confirms the accuracy of the network.

This study highlights the crucial role of flat plate collectors in solar dryer applications for drying agricultural produce. The aim is to develop a solar collector from discarded aluminium beverage cans, following the IS 1933, 2003 standard. The performance is evaluated at three different mass flow rates to dry 12 kg of green chillies. The cylindrical curved surfaces of the tubes are coated with a mixture of activated charcoal and blackboard paint to meet insulation standards. The total efficiency of the collector is determined by measuring the incoming and outgoing air temperatures at various mass flow rates. Additionally, the weight and moisture content removed from the 12 kg green chillies is monitored every 30 minutes throughout the day. The results show that efficiency decreases with increasing mass flow rates, with the solar collector achieving its highest efficiency of 67.89% at a mass flow rate of 0.005 kg/s, effectively removing 88% of the moisture content from the green chillies. This underscores the importance of optimising mass flow rates to maximize the efficiency of solar dryers using recycled materials. The use of activated charcoal and blackboard paint coatings on the aluminium cans enhances heat absorption and retention, contributing to the overall efficiency of the solar dryer. Future research could explore the application of this technology to other types of agricultural produce and further refine the coating materials to improve thermal performance.

This study presents a detailed numerical analysis of substrate boards made from various materials (FR-4, Si cladding, and Cu cladding) with nine electronic components mounted on them. Each component is subjected to different heat fluxes, and the analysis covers both natural convection (NC) and forced convection (FC) modes of heat transfer at air velocities of 4m/s and 6m/s. The findings reveal that at an air velocity of 6m/s, using a copper cladding board significantly lowers the temperatures of the electronic components by 340C to 540C compared to FR-4 and Si cladding boards. Additionally, the copper cladding reduces the required air-cooling velocity by 2m/s and achieves a temperature reduction for the IC chips ranging from 3.500C to 13.120C. It is recommended to use an air velocity of 4m/s with copper cladding to minimize fan power consumption while maintaining component temperatures below 1250C. These results provide crucial insights for thermal design engineers, aiding in the selection of appropriate substrate boards for effective thermal management of electronic components. The study emphasizes the benefits of copper cladding in distributing heat more uniformly, reducing energy consumption, and maintaining optimal operating temperatures. Furthermore, it suggests that placing high heat-dissipating components at inlet or outlet points can minimize thermal interactions and overall configuration temperatures. The research offers valuable guidance to the heat transfer community, particularly electronic thermal designers, by highlighting the importance of substrate material choice and component placement in enhancing the reliability and lifespan of integrated circuits (ICs). The comprehensive analysis and recommendations serve as a vital resource for optimizing thermal control strategies in electronic devices, ultimately contributing to improved performance and durability.

In the present study the experiments were conducted on steady-state that incorporated nine symmetric and asymmetric separate discrete integrated circuits (ICs), strategically positioned at different locations on a substrate board, both with and without phase-change material (PCM). These ICs were subjected to varying levels of heat flux. It has been noted that the temperature is highly influenced by variables such as the size and positions of integrated circuits (ICs), the heat flux applied to the ICs. Furthermore, the non-dimensional geometric distance parameter, λ, is notably affected by both the size and positioning of the ICs. It's observed that at a higher value of λ (0.19), the temperature decreases by 18.79% at a velocity of 3 m/s and by 26.48% at a velocity of 5 m/s without PCM. With PCM, the temperature drop is 23.58% at 3 m/s and 32.47% at 5 m/s. The correlation shows a regression of 0.97 and an RMS error of 0.012%. A proposed correlation establishes a connection between θ (non-dimensional temperature) and λ, suggesting that the maximum non-dimensional temperature (θ) decreases with an increase in λ. This implies that the maximum temperature of the integrated circuits (ICs) is reduced at higher λ values. These findings provide valuable insights for thermal design engineers, aiding them in optimizing the placement of integrated circuits (ICs) to improve the reliability and lifespan of the ICs.