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Energy efficiency of electrical infrared heating elements
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... UAVs equipped with infrared heaters emit infrared radiation to heat target surfaces, effectively melting ice layers without physical contact. This noncontact de-icing method ensures uniform heat distribution and penetrates the ice layer, reducing the risk of reformation, as illustrated in Figure 18; the infrared heater can be a quar halogen dichroic mirror lamp, FTE ceramic heater, or similar device [98,99]. ...
... Optimizing these radiative properties significantly enhances energy efficiency, improving system performance under various conditions [98]. Advanced measurement systems for evaluating radiation efficiency and heat flux distribution provide key data to refine infrared de-icing designs and improve overall performance [99]. These advancements support the development of UAV-based infrared de-icing systems for extreme environments, offering considerable potential for wider applications in challenging operational scenarios. ...
... Figure 18. Schematic of an infrared heating de-icing system [98,99]. ...
In cold environments, ice formation poses significant risks to infrastructure such as transportation systems and power transmission. Yet, traditional de-icing methods are often time-consuming, hazardous, and inefficient. In this regard, unmanned aerial vehicles (UAVs) have shown great potential in environmental ice detection and de-icing applications. This study comprehensively reviews the application of UAVs in ice detection and de-icing operations in external environments, emphasizing their potential to replace traditional manual methods. Firstly, the latest developments in UAV-based external ice detection technology are examined, with a focus on the unique capabilities of sensors such as multispectral cameras, infrared imagers, and LiDAR in capturing specific ice features. Subsequently, the implementation and effectiveness of chemical, mechanical, and thermal de-icing methods delivered via UAV platforms are evaluated, focusing on their operational efficiency and adaptability. In addition, key operational requirements are reviewed, including environmental adaptability, mission planning and execution, and command transmission, as well as system design and manufacturing. Finally, the practical challenges involved in deploying UAVs under complex weather conditions are examined and solutions are proposed. These are aimed at promoting future research and ultimately driving the adoption of UAV technology in de-icing applications.
... The comfort of working conditions in local working areas of large-sized premises [1][2][3][4] when using gas infrared heaters (GIH) as heating sources [5,6] is assessed based on air temperature and concentration of harmful substances [7,8]. The formation of temperature and gas concentration fields is carried out as a result of three interrelated processes that determine the transfer of heat [4] and anthropogenic oxides [9,10] formed during the GIH operation. ...
... The comfort of working conditions in local working areas of large-sized premises [1][2][3][4] when using gas infrared heaters (GIH) as heating sources [5,6] is assessed based on air temperature and concentration of harmful substances [7,8]. The formation of temperature and gas concentration fields is carried out as a result of three interrelated processes that determine the transfer of heat [4] and anthropogenic oxides [9,10] formed during the GIH operation. These processes include the heat transfer by radiation from the radiating surface of the GIH to the surfaces of enclosing structures and equipment, mixed convection in unevenly heated air and forced convection as a result of the air exchange system operation, the transfer of heat and contaminants as a result of mixed convection and FHMT, 2024 diffusion. ...
... The room under consideration was a closed rectangular area with an air atmosphere (Fig. 1). A gas infrared heater (1), a horizontal panel (simulating equipment, 2) and air inlet and outlet areas of the air exchange system (3,4) were located in the considered room. The solution area of the problem is selected based on possible practical applications of the modeling results. ...
... Modeling of mass transfer revealed a notable increase in the effective diffusion coefficient with rising surface temperature and thickness, with higher activation energy for thinner samples, indicating a pronounced dependence on irradiation temperature as thickness decreased [38]. A measurement system was developed to evaluate the radiant energy efficiency and heat flux distribution of infrared heaters, revealing that efficiency is strongly influenced by input power and, for in-plane efficiencies, by heater distance [39]. Airflow within the drying chamber is a particularly critical parameter in IR drying. ...
... Integration with smart control systems further enables precise regulation of heat output, adapting to specific processes and reducing energy consumption. These advancements collectively enhance the performance and reliability of infrared heaters in industrial applications, including drying and heating processes [30,39]. Hybrid drying systems, often referred to as IR-assisted drying, integrate infrared (IR) radiation with complementary drying methods to enhance both efficiency and product quality. ...
Infrared drying marks a revolutionary advancement in food processing, offering significant improvements in both operational efficiency and product integrity. By utilizing specific wavelengths of radiation, this approach achieves rapid, uniform heat transfer and effective moisture removal across a diverse range of food products. Its versatility spans applications in grains, fruits, vegetables, meats, seafood, and snack foods, adapting to the distinct requirements of each category. In addition to preserving the nutritional profile of food, this technique enhances rehydration properties and sensory attributes, ensuring superior consumer acceptance. It provides precise control over processing conditions, which helps retain texture, flavor, and bioactive compounds, even for delicate products. Practical insights underscore this method’s ability to reduce processing times and improve energy use, leading to cost-effective operations without compromising output quality. As an advanced drying technique, it surpasses traditional methods by addressing modern food production challenges. Compliance with regulatory standards ensures food safety and consistent quality, meeting stringent requirements. Infrared drying serves as a foundation for developing hybrid technologies, offering advanced strategies for specialized processing needs. This transformative innovation is poised to shape the future of food manufacturing, enabling progress while meeting evolving consumer and technological demands.
... Traditionally, with regard to efficiency, electric IR heaters have efficiencies ranging from 40% to 70%, whereas IR gas heaters have efficiencies ranging from 30% to 50% [43]. However, more recent studies have recorded efficiency as high as 85% [44], with efficiency not only dependent on the type of heater but on several other factors including reflectors, heating medium, air velocity, and, in the case of electric heaters, the type of filament [24,44]. ...
... Traditionally, with regard to efficiency, electric IR heaters have efficiencies ranging from 40% to 70%, whereas IR gas heaters have efficiencies ranging from 30% to 50% [43]. However, more recent studies have recorded efficiency as high as 85% [44], with efficiency not only dependent on the type of heater but on several other factors including reflectors, heating medium, air velocity, and, in the case of electric heaters, the type of filament [24,44]. ...
Food processing is a fundamental requirement for extending the shelf life of food products, but it often involves heat treatment, which can compromise organoleptic quality while improving food safety. Infrared (IR) radiation has emerged as a transformative technology in food processing, offering a rapid, energy-efficient method for inactivating microbial cells and spores while preserving the nutritional and sensory attributes of food. Unlike traditional heating methods, IR technology enhances heating homogeneity, shortens processing time, and reduces energy consumption, making it an environmentally friendly alternative. Additionally, IR processing minimizes water usage, prevents undesirable solute migration, and maintains product quality, as evidenced by its effectiveness in applications ranging from drying fruits and vegetables to decontaminating meat and grains. The advantages of IR heating, including its precise and even heat diffusion, ability to retain color and nutrient content, and capacity to improve the microbial safety of food, position it as a promising tool in modern food preservation. Nevertheless, there are gaps in knowledge with respect to optimal application of IR in foods, especially in the maintenance product quality and the impact of factors such as IR power level, temperature, wavelength (λ), food depth, and target microorganisms on the applicability of this novel technology in food systems. Recent research has attempted to address challenges to the application of IR in food processing such as its limited penetration depth and the potential for surface burns due to high energy which has delayed the widespread utilization of this technology in food processing. Thus, this review critically evaluates the application of IR in food safety and quality, focusing on factors that affect its effectiveness and its use to moderate food quality and safety while comparing its advantages/disadvantages over traditional thermal processing methods.
... Electric and exothermic methods, relying on conduction and convection, suffer from heat loss, unlike radiation heat transfer, which minimises such losses. A study found that the Net Frontal Radiant Efficiency (NFRE) of infrared heaters increased significantly compared to space heaters [5]. NFRE is a concept used to measure the effectiveness of a heating system, particularly radiant heating systems. ...
The heating pad was a mechanism for heating elements using steam as a heat source and heating the liquid inside a flexitank to liquidise for easy discharge completely. Alternative heat sources such as infrared, electric, and exothermic reactions may improve thermal performance for the heating process. Infrared heating is chosen for this study due to its efficient radiation heat transfer compared to conduction and convection. This study aims to determine the optimal infrared heater configuration to improve the time to liquidify fluid on the flexitank for easier discharge. Nine flexitank and infrared heater geometries were made using SolidWorks with different heater positions and heating element thicknesses. Each geometry was simulated using Ansys Mechanical to study the thermal performance of radiation heat transfer with three different heating element materials. The heat output and energy input obtained from the simulation were used to calculate heating time and energy efficiency, respectively. The effects of each parameter were studied to determine the best configuration of the infrared heater in terms of heating time, energy consumption and both. The results showed that the position of the heater plays the most crucial role in determining the heating time and energy consumption, as a heater position that produces a larger heated surface area on the flexitank can reduce heating time. The thickness of the heating element and its material contributes a minor impact on heating time and energy consumption. Increasing thickness would lower the heating time and increase energy efficiency if the thickness improves heat retention capabilities. Increasing material emissivity will increase the heating time. Higher conductive materials would use more energy compared to lower conductive materials. The heating time was improved by about 30% compared to a steam heating pad. Energy consumption was reduced by about 85% compared to a small steam generator. In conclusion, the infrared heater was a promising alternative as a heat source for flexitank applications.
... Brown et al. [4] calculated the efficiency of an industrial ceramic infrared heater by increasing its power up to 600 W and obtained a heat flux map in a volume of 500mm x 500mm x 500mm in front of the heater. As a similar study, Butturini HTFF 171-2 and Ngo [5] produced the heat flux distribution of 4 different types of infrared heaters on a plane (along the x and y axis) with measurements taken from the heaters with the help of a liquid-cooled heat flux sensor. ...
Unit heaters are self-contained heating units that burn natural gas or oil, or use electric-resistance to heat spaces in buildings. These heater types transfer heat to spaces via forced convection. An alternative to unit heaters are radiant infrared heaters. These heater types transfer heat to spaces via a mix of radiant and natural convection heat transfer. In essence, radiant infrared heaters directly radiate heat to the occupants and also warm the floor and other surfaces near the floor, which re-radiate heat to the occupants and warm the air near the floor. In contrast, unit heaters tend to heat spaces unevenly and much of the warm air output buoyantly rises to the ceiling in spaces with high ceilings. In general, radiant infrared heaters do not transfer heat to the overall space more efficiently than unit heaters but usually direct that heat more effectively to the occupants.
Radiant burners are used in drying, preheating, curing, and baking processes in the manufacturing industry. High radiation efficiency is one of the most important performance criteria for these burners. A wide range of radiation efficiencies (varying by more than 200% ) has been reported in the past for similar burners under similar operating conditions. The wide variation in reported radiation efficiencies appears to be due partly to the differences in the measurement techniques. If appropriate calibration source and procedures are used, the differences in data result from (1) nondiffuse emission from the burner and (2) nonuniform burner surface. The present article reports a technique for radiation efficiency measurements of diffuse and directional radiant burner surfaces. The technique is not sensitive to surface nonuniformities, which are common in commercial radiant burners. A calorimetric approach is used as a consistency check on the efficiency data obtained using the present technique. Companion measurements highlight the high degree of variability in the radiation efficiency results deduced from single-point radiation efficiency data, since they are based on the location of the sight tube with respect to the burner surface.
A project focusing on industrial infrared technology was carried out at Hydro-Québec's LTEE laboratory [1], The project required the optimization and use of a special test facility. Seven electric emitters and seven radiant gas burners typically used in the textile and pulp and paper industries were evaluated. Three types of experiments were carried out, providing four types of information: radiant flux maps, radiant efficiency evaluation, transient behavior characterization, and spectral emission characterization. The apparatus and the experimental procedures are described. Results are discussed and are presented in the form of tables and graphs. As the procedure and instruments used within each test were identical, this work furnishes rigorous data and objective information on both electric and gas IR technologies.
Direct fired heaters are used considerably in the energy related industries and petroleum industries for heating crude oil in the petroleum refining and petrochemical sectors. The aim of the current study is to formulate simple-to-use correlations to design the radiant and convective sections of direct fired heaters. The developed tools are easier than currently available models and involves a fewer number of parameters, requiring less complicated and shorter computations. Firstly, a simple correlation is developed to provide an accurate and rapid prediction of the absorbed heat in the radiant section of a fired heater, expressed as a fraction of the total net heat liberation, in terms of the average heat flux to the tubes, the arrangement of the tubes (circumferential), and the air to fuel mass ratio. Secondly, another simple correlation is developed to approximate external heat transfer coefficients for 75, 100, and 150Â mm nominal pipe size (NPS) steel pipes arranged in staggered rows and surrounded by combustion gases. Finally, a simple correlation is presented to predict the gross thermal efficiency as a function of percent excess air and stack gas temperature. This study shows that the proposed method has a good agreement with the available reliable data in the literature. The average absolute deviations between reported data and the proposed correlations are found to be around 1.5% demonstrating the excellent performance of proposed predictive tool. The proposed simple-to-use method can be of significant practical value for the engineers and scientists to have a quick check on the design of radiant and convective sections of direct fired heater. In particular, mechanical and process engineers would find the proposed approach to be user-friendly involving no complex expressions with transparent and easy to understand calculations.
Gas-fired radiant burners are used to convert fuel chemical energy into radiation energy for various applications. The radiation output of a radiant burner largely depends on the temperature of the combustion flame. In fact, the radiation output and, thus, the radiant efficiency increase to a great extent with flame temperature. Oxygen-enriched combustion can increase the flame temperature without increasing fuel cost. However, it has not been widely applied because of the high cost of oxygen production. In the present work, oxygen-enriched combustion of natural gas in porous radiant burners was studied. The oxygen-enriched air was produced passively, using polymer membranes. The membranes were shown to be an effective means of obtaining an oxygen-enriched environment for gas combustion in the radiant burners. Two different porous radiant burners were used in this study. One is a reticulated ceramic burner and the other is a ceramic fibre burner. The experimental results showed that the radiation output and the radiant efficiency of these burners increased markedly with rising oxygen concentrations in the combustion air. Also investigated were the effects of oxygen enrichment on combustion mode, and flame stability on the porous media.
Efficient radiant heating and cooling systems are promising technologies in slashing energy bills and improving occupant thermal comfort in buildings with low-energy demands such as houses and residential buildings. However, the thermal performance of radiant systems in buildings has not been fully understood and accounted for in currently available building energy simulation software. The challenging tasks to improve the applicability of radiant systems are the development of an accurate prediction model and its integration in the energy simulation software. This paper addresses the development of a semi-analytical model for radiant heating and cooling systems for integration in energy simulation software that use the one-dimensional numerical modeling to calculate the heat transfer within the building construction assemblies. The model combines the one-dimensional numerical model of the energy simulation software with a two-dimensional analytical model. The advantage of this model over the one-dimensional one is that it accurately predict the contact surface temperature of the circuit-tubing and the adjacent medium, required to compute the boiler/chiller power, and the minimum and maximum ceiling/floor temperatures, required for moisture condensation (ceiling cooling systems), thermal comfort (heating floor systems) and controls. The model predictions for slab-on-grade heating systems compared very well with the results from a full two-dimensional numerical model.
Thermoforming consists of warming a plastic sheet and forming it into a cavity or over a tool using vacuum, air pressure and mechanical means. The process begins by heating a thermoplastic sheet slightly above the glass transition temperature, for amorphous polymers, or slightly below the melting point, for semi-crystalline materials. As the final thickness distribution of the part is drastically controlled by the initial temperature distribution inside the sheet, it is very important to optimise the heating stage. In most of the thermoforming machine, this step is performed using an infrared oven constituted of long waves infrared emitters. The goal of this study is to determine the efficiency of short waves infrared emitters (halogen lamps) for the heating step. The infrared heating of thermoplastic sheets will be modelled following two steps: an experimental set-up developed in our laboratory permits to measure the influence of parameters such as heaters temperature, incidence of the radiation, heat transfer coefficient, etc. An 880 LW AGEMA infrared camera is used to evaluate the surface distribution of the transmitted heat flux by measuring the temperature distribution on the surface of the thermoplastic sheet. In addition, a numerical model using control volume method (software called PLASTIRAD) has been developed to simulate the heating stage. In particular, it takes into account the spectral properties of both heaters and plastic sheet as well as the heaters directivity. Comparisons between experimental data and numerical simulations allow validating the numerical model using different types of emitters and polystyrene (PS).