Journal articles: 'Design of heating surfaces'

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Smith, Jeremy R., Jérôme Leveneur, and John V. Kennedy. "Design of intelligent surfaces for energy intensive processing industry." MATEC Web of Conferences 185 (2018): 00001. http://dx.doi.org/10.1051/matecconf/201818500001.

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There are three different factors that can affect adhesion: the process fluid, the processing conditions and the surface of the processing equipment. Of these three factors, the surface properties of the processing equipment are the factor that offers the greatest opportunity for manipulation. The two key surface properties that have been identified to reduce adhesion are the surface energy and the surface topography. The surface energy of a material determines its degree of wettability and, a surface's affinity for water. In previous studies the surface energy of materials have been leveraged in order to create a surface with reduced levels of fouling through surface modification or the addition of polymer coatings with varying degrees of hydrophobicity. In addition, the topography of surfaces has been modified to reduce the level of particle adhesion. These modifications involve creating either a structured or random porous microstructure on the surface. Additional methods identified to reduce fouling include the application of liquid infused porous surfaces at low shear conditions and the use of non-contact heating through techniques such as microwave processing.

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Huo, Lin, and Tao Yang. "The Rapid Engineering Aero-Heating Calculation Method for Hypersonic Vehicles." Applied Mechanics and Materials 775 (July 2015): 59–67. http://dx.doi.org/10.4028/www.scientific.net/amm.775.59.

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The rapid engineering aero-heating calculation method for hypersonic vehicles is established for the question of computational efficiency during conceptual design stage. First the pressure distribution along vehicle’s surface is calculated by modified Newtonian theory. Secondly, the streamline along the surface is calculated with Newtonian steepest decent concept. Then by using reference enthalpy method, the heat flux on the surface is given. Finally, the heat flux on the surfaces of blunted cone, lifting body and wave-rider vehicle is calculated The analysis result shows the method used in this paper is fit for hypersonic vehicles, and can satisfies the aero-heating calculation during conceptual design stage in both efficiency and accuracy.

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Li, Jiquan, Taidong Li, Xiang Peng, Feng Liu, Hangchao Zhou, and Shaofei Jiang. "Optimal design of heating system for electrical rapid heat cycle mold based on multi-objective optimization, multiple-attribute decision-making, and conformal design theory." Advances in Mechanical Engineering 10, no. 8 (August 2018): 168781401878950. http://dx.doi.org/10.1177/1687814018789504.

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To improve the heating efficiency and cavity surface temperature uniformity, an optimal design method was developed for the heating system in electrical rapid heat cycle molding mold. First, an electrical rapid heat cycle molding mold was simplified as a single heating cell unit for thermal response analysis based on conformal design theory. Second, a response surface using back propagation neural network was constructed on the ground of initial finite element experiments. Then, a non-dominated sorting genetic algorithm-II combined with the polynomial back propagation neural network model was proposed to capture the Pareto-optimal solutions. Subsequently, the technique for order preference by similarity to ideal solution based on entropy-based weight was adopted as a multi-attribute decision-making method to choose the trade-off optimal design point from the Pareto-optimal set. To gain the optimal design of heating system, the optimized heating cell unit for electrical rapid heat cycle molding mold was calculated and finally mapped into the entire mold. Cavity surface temperature uniformity increased by 17.1%, and heating efficiency increased by 26%. The results show that the temperature distribution uniformity on the mold cavity surface was obviously improved and using this optimization strategy ensured high heating efficiency.

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Roland, Ulf, Frank Holzer, Ulf Trommler, Björn Höhlig, Markus Kraus, and Christian Hoyer. "Arrangements for radio-frequency heating of building structures." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 37, no. 6 (November 5, 2018): 1933–42. http://dx.doi.org/10.1108/compel-03-2017-0145.

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Purpose The aim of this study was to prove that radio-frequency (RF) energy with 13.56 MHz can be used for heating building structures in a controlled manner exploiting the advantage that homogeneous heating with sufficient penetration depths can be achieved. Design/methodology/approach Because parallel electrodes on both sides of the heated structure cannot be used in many practical applications, two special electrode designs have been developed by modeling the field distribution and energy absorption and by carrying out test experiments to validate the simulation results. Findings One solution is based on a two-dimensional surface capacitor providing certain penetration depths and being especially suitable for treating thin structures such as wooden parquet floor. Such an arrangement can be particularly used for pest control even when sensitive surfaces have to be protected. The other solution uses a capacitive coupling between the grounded shielding and an electrode or an equivalent structure (e.g. moist soil) at the other side of the masonry to establish a sufficiently strong electrical field between a “hot” electrode on the side of the shielding and the coupled rear electrode. Originality/value Both solutions significantly enhance the application potential of RF heating.

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Kula, P., T. Liskiewicz, and T. Pacyniak. "Surface Heat Treatment Design Methodology of Large-Scale Castings." Materials Science Forum 513 (May 2006): 61–68. http://dx.doi.org/10.4028/www.scientific.net/msf.513.61.

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The process of induction heating followed by forced cooling of large-scale castings is considered. The main goal of this study is to develop a reliable design methodology of surface heat treatment process to provide high quality of the treated component. It is assured by determination of the material constants and convection coefficient during heating and cooling experiments carried out on the specimens made of material adequate to the considered large-scale casting. The main part of the investigations was preceded by wide analyses of the mechanical and chemical properties of the tested specimens. The presented global design methodology of large-scale castings gives a possibility to predict the temperature distribution on the hardened surface during induction heating and forced cooling. This allows to select the most adequate parameters and apply them in a real specific process. The obtained results have been analyzed and discussed.

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Boiko, E. A., and I. V. Zagorodnii. "Integrated research of slaging intensityof the boilerunit heating surfaceswhen burning non-project fuels." Power engineering: research, equipment, technology 22, no. 6 (March 26, 2021): 101–16. http://dx.doi.org/10.30724/1998-9903-2020-22-6-101-116.

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THE PURPOSE. Comprehensive research of the slagging intensity is the heating surfaces of the BKZ-420-140 boiler unit with solid slag removal at the Abakan CHP when burning non-project fuels. The relevance of the work is due to the technical necessity and economic feasibility of conversion boiler units to combustion of non-design coals. METHODS. The problem has been analyzed by methodology for conducting complex tests, measurements and processing of experimental data, as well as the results of experimental and computational studies of a boiler unit when operating on coals of various qualities. RESULTS. Qualitative and quantitative parameters for assessing the properties of off-design coals and their behavior in real operating conditions of radiation, semi-radiation and convective conditions, taking into account their modes and design functions, have been obtained. CONCLUSION: A computational analysis of the operating modes of boiler units when burning non-design fuels showed that a promising technology for involving non-design coals in the fuel and energy balance of a thermal power plant is providing a scientifically based mixture of design and nondesign fuels.Analysis of the slagging and polluting properties of non-design coals makes it possible to predict changes in the characteristics of the thermal efficiency of heating surfaces and to develop many practical recommendations for optimizing the parameters of the cleaning equipment installed on the boiler.Also, mixtures of fuels were determined for which the wall temperatures of the metal of the outlet stack of the superheater increase, which significantly reduces the strength characteristics of the surface.The assessment and prediction of the reliability of the heating surface is carried out by calculating the temperature of the metal wall in the most heat-stressed place.

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Collazo-Davila, C., E. Landree, D. Grozea, G. Jayaram, R. Plass, P. C. Stair, and L. D. Marks. "Design and Initial Performance of an Ultrahigh Vacuum Sample Preparation Evaluation Analysis and Reaction (SPEAR) System." Microscopy and Microanalysis 1, no. 6 (December 1995): 267–79. http://dx.doi.org/10.1017/s1431927695112672.

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Results concerning the calibration and use of a new ultrahigh vacuum (UHV) surface preparation and analysis system are reported. This Sample Preparation Evaluation Analysis and Reaction (SPEAR) side chamber system replaces an older surface side chamber that was attached to a Hitachi UHV H-9000 microscope. The system combines the ability to prepare clean surfaces using sample heating, cooling, ion milling, or thin film growth with surface analytical tools such as Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM), along with atomic surface structure information available from high-resolution transmission electron microscopy (HREM). The chemical sensitivity of the XPS and AES are demonstrated in preliminary studies of catalytic and semiconductor samples. In addition, the surface preparation capabilities are also demonstrated for the Si(100) and Ge(100) surfaces, including the ability to acquire secondary electron images during milling. During operation, the entire system is capable of maintaining the UHV conditions necessary for surface studies.

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Koptev, A. ""THEORETICAL ASPECTS OF STRENGTH AND THERMAL CONTROL OF HYPERSONIC AIRCRAFT"." National Association of Scientists 1, no. 66 (May 14, 2021): 54–60. http://dx.doi.org/10.31618/nas.2413-5291.2021.1.66.403.

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This article analyzes the theoretical aspects of controlling the strength and thermal modes of hypersonic aircraft. The conditions for the functioning of hypersonic aircraft were also investigated, and problematic situations for their design were identified. The parameters of aerodynamic heating of surfaces and heating of thermal protection of hypersonic aircraft were estimated with an assessment of the parameters of thermal protection of hypersonic aircraft and the magnitude of the heat flux supplied to the surface, with the determination of the parameters of their thermal protection, taking into account the thermophysical characteristics of materials from thermal parameters.

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Peng, Zhiwei, Jiann-Yang Hwang, and Matthew Andriese. "Design of double-layer ceramic absorbers for microwave heating." Ceramics International 39, no. 6 (August 2013): 6721–25. http://dx.doi.org/10.1016/j.ceramint.2013.01.114.

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Ren, Xian Hong, Kang Tao Hu, Jian Chun Zhang, Ai Cheng Liu, and Hai Rui Yang. "Design and Development of 850t/h CFB Boiler with Energy Saving Technology." Applied Mechanics and Materials 492 (January 2014): 13–18. http://dx.doi.org/10.4028/www.scientific.net/amm.492.13.

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Taiyuan Boiler Group Co. Ltd. designed and developed an 850t/h CFB boiler with energy saving technology on the principle of “State Specification Design Theory”. By measuring the ash formation and attrition characteristic of the design coal, with the one dimension mass balance model developed by Tsinghua University, the bed quality of the bed inventory and the pressure drop were modified. Based on the particle density calculated, the heating transfer coefficients were chosen and the arrangements of the heating surfaces were modified. According to the special operation conditions of the user, the practical working conditions for the boiler are determined so as to assure the technical characteristics and structural properties in 850t/h CFB boiler.

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Kaczorek, Dobrosława, and Halina Koczyk. "STRUCTURAL SOLUTIONS IMPACT ON THERMAL ENERGY EFFICIENCY OF HEATING SURFACE AT AN OPEN SPACE." Journal of Civil Engineering and Management 19, no. 6 (December 24, 2013): 883–93. http://dx.doi.org/10.3846/13923730.2013.840333.

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This paper presents studies on thermal energy efficiency of heating surface at an open space according to structural solutions and climatic conditions. Numerical simulation research was conducted to assess three different types of heating surfaces at an open space over chosen period of time in real weather conditions. Performance parameters such as surface temperature, supply temperature and efficiency of heating surface relative to constructional designs and model of control strategy used were analysed. The number, thickness and type of material layers beneath ground level were modified. The distance between heating pipes and their diameters were kept constant. The carried out analyses show that the used solutions can lead to significant differences in the performance and consequently in the energy efficiency of the heating system for open spaces.

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Bui, Huy-Tien, and Sheng-Jye Hwang. "Design of an induction heating coil coupled with magnetic flux concentrators for barrel heating of an injection molding machine." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 229, no. 3 (June 5, 2014): 518–27. http://dx.doi.org/10.1177/0954406214537806.

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In an injection molding machine, the conventional barrel heating system which uses resistance heating method (RH) has some drawbacks such as low heating rate, long heating time, and energy loss. With induction heating (IH) technique, the barrel can better handle almost all of these disadvantages. However, non-uniform temperature distribution on inside surface of a barrel is the main drawback of induction heaters. A working coil coupled with magnetic flux concentrators via adjustment of magnetic flux concentrator spacing to achieve uniformity of magnetic flux and temperature distribution on the inside surface of a barrel was proposed and experimented. Results showed that, when barrel was heated by induction heating method with the proposed induction heating coil, heating time to reach a specific temperature could be reduced, and heating rate increased compared to resistance heating method. With 8 mm pitch of magnetic flux concentrators on a coil, the temperature distribution was the most uniform.

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Watschke, Hagen, Karl Hilbig, and Thomas Vietor. "Design and Characterization of Electrically Conductive Structures Additively Manufactured by Material Extrusion." Applied Sciences 9, no. 4 (February 22, 2019): 779. http://dx.doi.org/10.3390/app9040779.

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Multi-material additive manufacturing offers new design freedom for functional integration and opens new possibilities in innovative part design, for instance, a local integration of electrically conductive structures or heat radiant surfaces. Detailed experimental investigations on materials with three different fillers (carbon black (CB), carbon nanotubes (CNT) and nano copper wires) were conducted to identify process-specific influencing factors on electrical conductivity and resistive heating. In this regard, raster angle orientation, extrusion temperature, speed and flow rate were investigated. A variation of the raster angle (0°, ±45°, and 90°) shows the highest influence on resistivity. An angle of 0° had the lowest electrical resistance and the highest temperature increase due to resistive heating. The material filled with nano copper wires showed the highest electrical conductivity followed by the CNT filled material and materials filled with CB. Both current–voltage characteristics and voltage-dependent heat distribution of the surface temperature were determined by using a thermographic camera. The highest temperature increase was achieved by the CNT filled material. The materials filled with CB and nano copper wires showed increased electrical resistance depending on temperature. Based on the experiments, solution principles and design rules for additively manufactured electrically conductive structures are derived.

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14

Forcucci, S. J., and T. H. Kwon. "A Computer Aided Design System for Three-Dimensional Compression Mold Heating." Journal of Engineering for Industry 111, no. 4 (November 1, 1989): 361–68. http://dx.doi.org/10.1115/1.3188773.

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Compression mold processing of composites involves taking the charge through a material dependent temperature and pressure path, inducing thermochemical reactions to cure the charge. While curing, specific uniform temperatures are required for a time, and spatial variation of the cavity surface temperature can lengthen time needed to cure and also cause voids and residual stresses, reducing the quality of the finished part. Towards mold heating design goal of uniform cavity surface temperature, an interactive CAD system for compression mold heating design has been developed. The system accepts a previously defined three dimensional, discretized goemetry and uses a Boundary Element Method (BEM) analysis which includes the effects of long, thin electric resistor heating rods, and is coupled with the CONMIN algorithm for constrained minimization of an objective error function to obtain uniform temperature over the cavity surface. Realistic constraints are featured to insure design feasibility. The problem is organized with design in mind to allow fast, easy redesign and a sensitivity study along with the optimization. The approach used is unique and is the first application of this type of optimization to three dimensional mold heating design. An example of the whole design process including creation, reviewing, optimization, and redesign of curved mold example is presented for results.

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Li, Jian, Tiecheng Luo, Hantao Wen, Jiajia Deng, Mingyang Wu, Ya Li, Gang Wang, and Yanli Pei. "Design and regularity research of MOCVD heating plate based on experiments and simulations." Vacuum 174 (April 2020): 109174. http://dx.doi.org/10.1016/j.vacuum.2020.109174.

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Cairncross, R. A., S. Jeyadev, R. F. Dunham, K. Evans, L. F. Francis, and L. E. Scriven. "Modeling and design of an industrial dryer with convective and radiant heating." Journal of Applied Polymer Science 58, no. 8 (November 21, 1995): 1279–90. http://dx.doi.org/10.1002/app.1995.070580809.

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Yadav, Vipin, and Keshav Kant. "Convective Cooling of a PCB Like Surface With Mixed Heating Conditions in a Vertical Channel." Journal of Electronic Packaging 129, no. 2 (July 23, 2006): 129–43. http://dx.doi.org/10.1115/1.2721084.

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Printed circuit boards (PCBs) with uniform surface temperature and uniform wall heat flux are ideal to study. However, in reality, the heating conditions existing on the PCB surfaces are much different from the ideal ones. Present attempts have been made to study different combinations of uniform heat flux (UHF) and uniform wall temperature (UWT) heating conditions on a single surface and to develop more realistic relationships between various flow and thermal parameters for evaluating the local and averaged Nusselt number. Both the numerical and experimental investigations were undertaken to study partial and mixed UHF and UWT heating conditions on a buoyancy assisted convection cooling of simulated PCB forming one wall of the vertical channel while, the other wall was kept insulated. The current work considers moderate to high flow Reynolds number (14.1×103≤Re≤2.35×105) in the channel and range of heat fluxes near that occurring in electronic cooling applications using air as a coolant (0.0<q≤5.0W∕cm2). Data for heat flux and Nusselt number occurring at various locations of the plate surface under different heating conditions are presented to analyze variation patterns; and an empirical relation is put forward which is capable of predicting Nu under the heating conditions mentioned. The empirical expression obtained can be used for getting an optimized layout of the PCBs inside the equipment cabinet, thus resulting in better design for more reliable and safe operation under potentially harsh environment and/or maximum load condition.

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Barber, J. R., T. W. Beamond, J. R. Waring, and C. Pritchard. "Implications of Thermoelastic Instability for the Design of Brakes." Journal of Tribology 107, no. 2 (April 1, 1985): 206–10. http://dx.doi.org/10.1115/1.3261021.

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Thermal distortion in brakes due to frictional heating causes localized contact and high temperatures (hot spots) with consequent thermal damage to the sliding components. This paper examines the effect of brake design and operating parameters on the maximum temperature reached. Previous solutions for steady-state sliding are reviewed and the effects of hot spots being in intermittent contact due to the geometric design of the brake are discussed. Approximate solutions for transient thermoelastic contact are extended to the case of uniform deceleration to determine the duration of the stop for which thermoelastic effects will be significant. If the stop is sufficiently slow for hot spots to develop, the temperatures will generally be high. However, high temperatures are also reached in sufficiently rapid stops due to the high rate of energy dissipation. An optimum is found between these extremes.

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Schmatloch, V., and S. Rauch. "Design and characterisation of an electrostatic precipitator for small heating appliances." Journal of Electrostatics 63, no. 2 (February 2005): 85–100. http://dx.doi.org/10.1016/j.elstat.2004.08.001.

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Wen, Mao Yu, Ching Yen Ho, and Kang Jang Jang. "Characteristics of Pool Boiling Heat Transfer from Sintered Surfaces." Advanced Materials Research 566 (September 2012): 382–85. http://dx.doi.org/10.4028/www.scientific.net/amr.566.382.

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This study investigated the effect of design parameters on pool boiling heat transfer on the sintered surfaces of a tube. The pool boiling experiments were conducted in saturated, deionized and degassed water. Data were taken at an atmospherical pressure and a fixed heat flux of 41,000 . In the experimentation, the effects of the sintering pressure, sintering time, sintering temperature, heating rate, and particle size on the boiling heat-transfer coefficient of the sintered surface were investigated using the Taguchi method, and an orthogonal array table was selected as an experimental plan for some parameters mentioned above. Based on the results of SN (signal/noise) ratio and ANOVA (Analysis of Variance), the optimal conditions of specifications of parameters will be provided. It was found that all the chosen sintering factors have significant effects on the pool boiling heat transfer coefficient. Optimum pool boiling heat transfer coefficient of 5.29 was achieved with a sintering pressure of 2 atmospheres, a sintering time of 2 hr, a sintering temperature of 900 °C, a heating rate of 5 °C/min and a particle size of 0.35 mm in a nitrogen container.

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Yum, Sang-Guk, Huiming Yin, and Sung-Hwan Jang. "Toward Multi-Functional Road Surface Design with the Nanocomposite Coating of Carbon Nanotube Modified Polyurethane: Lab-Scale Experiments." Nanomaterials 10, no. 10 (September 24, 2020): 1905. http://dx.doi.org/10.3390/nano10101905.

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A novel multi-functional road surface system is designed to improve safety, the efficiency of traffic flow, and environmental sustainability for future transportation systems. The surface coating, preforming temperature detection with heating element and hydrophobic features, were fabricated with a nanocomposite consisting of carbon nanotube (CNT) modified polyurethane (PU). The CNT/PU coating showed higher electrical conductivity as well as enhanced hydrophobic properties as the CNT concentration increased. The multifunctional properties of CNT/PU coatings were investigated for use in freezing temperature sensing and heating. The CNT/PU coatings showed high temperature sensitivity in the freezing temperature range with a negative temperature coefficient of resistance. In addition, the CNT/PU coatings had excellent heating performance due to the Joule heating effect. Therefore, the proposed CNT/PU coatings are promising for use as multifunctional road coating materials for detection of freezing temperature and deicing by self-heating.

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Liu, Bernard Haochih, Fang-Yi Liao, and Jian-Hong Chen. "Design, fabrication, and characterization of electroless Ni–P alloy films for micro heating devices." Thin Solid Films 537 (June 2013): 263–68. http://dx.doi.org/10.1016/j.tsf.2013.04.136.

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He, Zhiqiang, Heping Xie, Mingzhong Gao, Ling Chen, Bo Yu, Yunqi Hu, and Jianping Yang. "Design and Verification of a Deep Rock Corer with Retaining the In Situ Temperature." Advances in Civil Engineering 2020 (September 15, 2020): 1–13. http://dx.doi.org/10.1155/2020/8894286.

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Deep rock is always under high-temperature conditions. However, traditional coring methods generally have no thermal insulation design, which introduces large deviations in the guidance required for resource mining. Thus, a thermal insulation design that utilizes active and passive thermal insulation was proposed for deep rock corers. The rationale behind the active thermal insulation scheme was to maintain the in situ core temperature through electric heating that was controlled by using a proportional-integral-derivative (PID) chip. Graphene heating material could be used as a heating material for active thermal insulation through testing. In regard to the passive thermal insulation scheme, we conducted insulation and microscopic and insulation effectiveness tests for hollow glass microsphere (HGM) composites and SiO2 aerogels. Results showed that the #1 HGM composite (C1) had an excellent thermal insulation performance (3 mm thick C1 can insulate to 82.6°C), high reflectivity (90.02%), and wide applicability. Therefore, C1 could be used as a passive insulation material in deep rock corers. Moreover, a heat transfer model that considered multiple heat dissipation surfaces was established, which can provide theoretical guidance for engineering applications. Finally, a verification test of the integrated active and passive thermal insulation system (graphene heating material and C1) was carried out. Results showed that the insulating effect could be increased by 13.3%; thus, the feasibility of the integrated thermal insulation system was verified. The abovementioned design scheme and test results provide research basis and guidance for the development of thermally insulated deep rock coring equipment.

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Li, Xi-Ping, Guo-Qun Zhao, Yan-Jin Guan, and Ming-Xing Ma. "Optimal design of heating channels for rapid heating cycle injection mold based on response surface and genetic algorithm." Materials & Design 30, no. 10 (December 2009): 4317–23. http://dx.doi.org/10.1016/j.matdes.2009.04.016.

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Jiang, Pengfei, Danlei Zhang, Bin Li, and Chao Song. "Design and Numerical Simulation of In-Situ Pyrolysis of Oil Shale Through Horizontal Well Fracturing with Nitrogen Injection." International Journal of Heat and Technology 39, no. 2 (April 30, 2021): 417–23. http://dx.doi.org/10.18280/ijht.390210.

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An in-situ pyrolysis technology was proposed for shallow oil shale: drilling horizontal wells to the oil shale formation, connecting the horizontal well sections through hydraulic fracturing, injecting nitrogen from the surface to bottomhole, heating up the nitrogen to a high temperature at the bottom, and directly using the high-temperature nitrogen for oil shale pyrolysis. Then, a mathematical model was established for the heat transfer within the oil shale, and a simplified physical model was created for in-situ pyrolysis of oil shale, and used to simulate the heat transfer process. The simulation results show that, with the extension of heating time, the area of effectively pyrolyzed oil shale formation took up an increasingly large proportion of the total cross-sectional area of the formation; however, the increase of the pyrolysis area ratio was rather slow, and the temperature was unevenly distributed in the formation after a long duration of heating. Therefore, the 300d in-situ heating was split into two stages: 250d of heating in the heating well and 50d of heating in the production well. The two-stage heating maximized the heating area of oil shale, and heated 57% of the cross-sectional area up to 400℃, ensuring the effectiveness of pyrolysis. Moreover, this heating scheme ensured an even distribution of temperature in oil shale formation, a high energy utilization, and a desirable heating effect.

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Rasmussen, C., R. E. Gallery, and J. S. Fehmi. "Passive soil heating using an inexpensive infrared mirror design – a proof of concept." SOIL Discussions 2, no. 1 (May 11, 2015): 427–48. http://dx.doi.org/10.5194/soild-2-427-2015.

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Abstract. There is need to understand the response of soil systems to predicted climate warming for modeling soil process response to climate warming. Current methods for soil warming include expensive and difficult to implement active and passive techniques. Here we test a simple, inexpensive in situ passive soil heating approach, based on easy to construct infrared mirrors that do not require automation or enclosures. The infrared mirrors consisted of 61 × 61 cm glass panels coated with infrared reflecting film. The mirrors as constructed are effective for soil heating in environments typified by open canopy and low canopy vegetation. Mirror tests were performed on several soils in a warm semiarid environment. Results indicated that the infrared mirrors yielded significant heating and drying of soil surface and shallow subsurface relative to un-warmed control treatments, and that warming and drying effects was soil specific with greater potential warming on soils with lower volumetric heat capacity. Atmospheric and soil moisture attenuated mirror induced soil warming. The results demonstrate proof-of-concept that the infrared mirrors may be used to passively heat the near soil surface, providing an inexpensive, low-maintenance alternative to other passive and active soil heating technologies.

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Li, Jian, and Zhi Xiong Huang. "Design of Thermal Transferring of Plane Mould for Low Pressure Sheet Molding Compound." Applied Mechanics and Materials 44-47 (December 2010): 2607–11. http://dx.doi.org/10.4028/www.scientific.net/amm.44-47.2607.

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Mathematical simulation of mold flow of glass fibers and design of heat transferring of plane mould for low pressure sheet molding compound were analyzed and optimized by MATLAB software in this article. The flexural properties of specimens molded in conventional and thermal-deign optimized mould were compared. The fracture surfaces of specimens were carefully investigated by SEM, too. The results show that the surface temperature of the mould was highly uniform during the process of curing when the distribution of the heating pipes in the plane mould was optimized. The flexural strengths of the specimens, cut from the center and the corner of the parts molded by thermal optimized mould, are almost the same and can reach about 170MPa. And the distribution of glass fiber with high weight content adhering well with resin is uniform in the fracture area.

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Luo, Xuan, Tianzhen Hong, and Yu-Hang Tang. "Modeling Thermal Interactions between Buildings in an Urban Context." Energies 13, no. 9 (May 9, 2020): 2382. http://dx.doi.org/10.3390/en13092382.

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Thermal interactions through longwave radiation exchange between buildings, especially in a dense urban environment, can strongly influence a building’s energy use and environmental impact. However, these interactions are either neglected or oversimplified in urban building energy modeling. We developed a new feature in EnergyPlus to explicitly consider this term in the surface heat balance calculations and developed an algorithm to batch calculating the surrounding surfaces’ view factors using a ray-tracing technique. We conducted a case study with a district in the Chicago downtown area to evaluate the longwave radiant heat exchange effects between urban buildings. Results show that the impact of the longwave radiant effects on annual energy use ranges from 0.1% to 3.3% increase for cooling and 0.3% to 3.6% decrease for heating, varying among individual buildings. At the district level, the total energy demand increases by 1.39% for cooling and decreases 0.45% for heating. We also observe the longwave radiation can increase the exterior surface temperature by up to 10 °C for certain exterior surfaces. These findings justify a detailed and accurate way to consider the thermal interactions between buildings in an urban context to inform urban planning and design.

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Ivanova, Tatyana N. "Design and technological methods of reducing of thermal stress in grinding process." MATEC Web of Conferences 224 (2018): 01006. http://dx.doi.org/10.1051/matecconf/201822401006.

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When grinding wheel comes in contact with machined surface thermal coupling occurs between the detail, shavings and cooling lubrication fluid. Depending on machining conditions, heat passes into detail machined from 50 to 83% which results in steel defects. Using results of carried research of thermal fields, thermal processes in grinding operations may be controlled. Through these processes we control quality of upper layer. As the result of carried research the next data are obtained: functional dependence, which allows calculating of rate of heating and cooling for every part of detail to be machined according to machining mode, time and intensity of heating source; dependence of stress calculation on operating time and temperature of heating source while grinding process is carried

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Puzanov, O. "Employment of electric torch discharge and a steam-gas generator in surface schooping of materials." RADIOFIZIKA I ELEKTRONIKA 25, no. 4 (2020): 66–79. http://dx.doi.org/10.15407/rej2020.04.066.

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Subject and Purpose. The present paper is concerned with the method of surface schooping of materials using high-frequency torch discharge (HFTD) and glycerol vapor as a base for dissolving activating additives to the working gas. To approach the problem, a steam generator is employed in an effort to improve the HFTD catalytic performance in the activation of surfaces and deposition of coatings on them. The purpose is to develop a design technique of a steam generator intended for making a proper gas environment in the HFTD burning area. The discussed design techniques seek to enhance efficiency of the self-contained steam generator with allowance for its small size compared to the wavelength. Methods and Methodology. The analysis of the glycerol vapor behavior in the HFTD plasma depends on the knowledge of glycerol molecule ionization potential in the electron impact case. To find out about the measure to which the glycerol vapor affects the HFTD current, a known calcium ionization potential is used as a defined point. The heating elements as part of the steam generator are designed in terms of thermal design methodology adopted in the electroheating machine making. The calculation formulas of the running time ratios of the steam generator with various heating elements and energy efficiencies have been obtained in terms of galvanic cell theory. Results. It has been shown that glycerol vapor itself cannot affect the HFTD current. For the HFTD excitation, the microwave region has been chosen. In cooperation with activating additives to the discharge plasma, this factor also adds to the HFTD current increase. Hence, the HFTD catalytic performance depends not only on the HFTD energy and its excitation field frequency but on the glycerol-dissolved additives as well. A special design has been developed for the heating element as part of a small-size steam generator. Reference tables have been composed, enabling one to pick up a prpoper diameter and number of parallel connected wires in the spiral coil. Conclusion. A good use of glycerol vapor as a base for vaporous fluxes and activating additives to the HFTD working gas has been shown. The developed design technique concerning the heating element of the steam generator optimizes its heating circuit. Specifically, it enhances the steam generation and reduces the power consumption of the steam generator running on the galvanic cell. Second, it makes it possible to use stainless-steel spiral heating coils in regime of automatic temperature control.

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Betancourt Astete, Robinson, Nicolás Gutiérrez-Cáceres, Marcela Muñoz-Catalán, and Tomas Mora-Chandia. "Direct Improvement in the Combustion Chamber and the Radiant Surface to Reduce the Emission of Particles in Biomass Cooking Stoves Used in Araucanía, Chile." Sustainability 13, no. 13 (June 27, 2021): 7205. http://dx.doi.org/10.3390/su13137205.

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Solid particle emissions from burning wood in three internal combustion biomass cooking stoves commonly used in southern Chile were compared. Each stove was used to show differences in sealing systems, combustion chamber shape, and heating surfaces in order to optimize biomass combustion and the energy produced at a low manufacturing cost. The influence of cooking stove design along with particle and gas emissions that resulted from the biomass combustion within the cooking stove was investigated in this study. Levels of diverse atmospheric contaminants, such as particulate matter, emission factor, NOx, CO2, and CO, and the temperature of the flue gases were determined with the Ch-28 method and UNE-EN 12815. The average emission of particulate matter was significantly reduced by modifying the geometry of the combustion chamber and heating surface of each stove, resulting in 5 g/h particle emissions in conventional equipment and 2 g/h in the improved equipment. In relation to gas emissions, there was a 25% maximum decrease in NOx gases and 35% in CO after modifying the heating surface of each stove. This background supports the evidence of technological improvement with high environmental impact and low economic cost for local manufacturers.

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Zhang, Ying, Thomas Olofsson, Gireesh Nair, Chenbo Zhao, Bin Yang, and Angui Li. "Cold windows induced airflow effects on the thermal environment for a large single-zone building." E3S Web of Conferences 172 (2020): 06003. http://dx.doi.org/10.1051/e3sconf/202017206003.

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With access to modern building technologies and HVAC-systems, it is possible to obtain low energy use and good thermal comfort for complex design, such as large building volumes. However, the situation is different for large single zone buildings with large volumes. They often have insufficient thermal comfort. The problem could be partially attributed to the unwanted airflows due to the cold surfaces, especially the windows. With increased knowledge of the airflow, it is possible to identify suitable renovation strategies in such buildings. In this work, we study a church building with mechanical air change system and floor heating. CFD-simulations with dynamic airflow was conducted based on building geometries and technical data. The validation was based on data from the ventilation control and the space-heating system. The results show how the window-to-wall ratios and the positions of windows affect the thermal comfort. It contributes with knowledge of advantages and disadvantages of different envelope design in the existing environment with floor heating.

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Wang, Guilong, Guoqun Zhao, and Yanjin Guan. "Research on optimum heating system design for rapid thermal response mold with electric heating based on response surface methodology and particle swarm optimization." Journal of Applied Polymer Science 119, no. 2 (July 29, 2010): 902–21. http://dx.doi.org/10.1002/app.32771.

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Shin, Mi Su, Kyu Nam Rhee, Seong Ryong Ryu, Myoung Souk Yeo, and Kwang Woo Kim. "Design of radiant floor heating panel in view of floor surface temperatures." Building and Environment 92 (October 2015): 559–77. http://dx.doi.org/10.1016/j.buildenv.2015.05.006.

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Techawanitchai, Prapatsorn, Kazuya Yamamoto, Mitsuhiro Ebara, and Takao Aoyagi. "Surface design with self-heating smart polymers for on–off switchable traps." Science and Technology of Advanced Materials 12, no. 4 (August 2011): 044609. http://dx.doi.org/10.1088/1468-6996/12/4/044609.

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Pitonak, Anton, Martin Lopusniak, and Miloslav Bagona. "Case Study of the Straw Bale House." Applied Mechanics and Materials 861 (December 2016): 577–84. http://dx.doi.org/10.4028/www.scientific.net/amm.861.577.

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Straw is renewable material both from the ecological and environmental point of view. It is almost always available at construction sites. Straw is used mainly as filling thermal insulation in structures. This paper deals with design of a two-generation family house. The family house is located in the eastern Slovakia. There is the temperature zone -14 °C. The first goal of this project was to specify the optimal ratio between solid and glazed surfaces in distribution of the specific heat use for space heating. The second goal was to achieve the specific heat use for space heating lower than 15 kWh·m-2·a-1. The specific heat use for space heating has been calculated according to STN EN ISO 13 790 Energy performance of buildings. The project analysed forced ventilation with the heat recovery unit, orientation towards cardinal points, optimal ratio of glazed and solid surfaces of the designed house and their impact on energy performance of buildings. Individual parameters were mutually combined and required goal has been achieved. The specific heat use for space heating was less than 15 kWh·m-2·a-1 in 13 of the evaluated combinations.

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Bambara, James, and Andreas K. Athienitis. "Energy and Economic Analysis for Greenhouse Envelope Design." Transactions of the ASABE 61, no. 6 (2018): 1795–810. http://dx.doi.org/10.13031/trans.13025.

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Abstract. The energy consumption of a building is significantly impacted by its envelope design, particularly for greenhouses where coverings typically provide high heat and daylight transmission. Energy and life cycle cost (LCC) analysis were used to identify the most cost-effective cladding design for a greenhouse located in Ottawa, Ontario, Canada (45.4° N) that employs supplemental lighting. The base case envelope design uses single glazing, whereas the two alternative designs consist of replacing the glass with twin-wall polycarbonate and adding foil-faced rigid insulation (permanent or movable) on the interior surface of the glass. All the alternative envelope designs increased electricity consumption for lighting and decreased heating energy use except when permanent or movable insulation was applied to the north wall and in the case of permanent insulation on the north wall plus polycarbonate on the east wall. This demonstrates how the use of reflective opaque insulation on the north wall can be beneficial for redirecting light onto the crops to achieve simultaneous reductions in electricity and heating energy costs. A maximum reduction in LCC of 5.5% (net savings of approximately $130,000) was achieved when permanent insulation was applied to the north and east walls plus polycarbonate on the west wall. This alternative envelope design increased electricity consumption for horticultural lighting by 4.3%, reduced heating energy use by 15.6%, and caused greenhouse gas emissions related to energy consumption to decrease by 14.7%. This analysis demonstrates how energy and economic analysis can be employed to determine the most suitable envelope design based on local climate and economic conditions. Keywords: Artificial lighting, Consistent daily light integral, Energy modeling, Envelope design, Greenhouse, Life cycle cost analysis, Light emitting diode, Local agriculture.

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Kornienko, Victoria, Mykola Radchenko, Roman Radchenko, Dmytro Konovalov, Andrii Andreev, and Maxim Pyrysunko. "Improving the efficiency of heat recovery circuits of cogeneration plants with combustion of water-fuel emulsions." Thermal Science, no. 00 (2020): 154. http://dx.doi.org/10.2298/tsci200116154k.

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When using modern highly efficient internal combustion engines with lowered potential of exhaust heat the heat recovery systems receive increasing attention. The efficiency of combustion exhaust heat recovery at the low potential level can be enhanced by deep cooling the combustion products below a dew point temperature, which is practically the only possibility for reducing the temperature of boiler exhaust gas, while ensuring the reliability, environmental friendliness and economy of power plant. The aim of research is to investigate the influence of multiplicity of circulation and temperature difference at the exit of exhaust gas boiler heating surfaces, which values are varying as 20, 15, 10?C, on exhaust gas boiler characteristics. The calculations were performed to compare the constructive and thermal characteristics of the various waste heat recovery circuits and exhaust gas boiler of ship power plant. Their results showed that due to application of condensing heating surfaces in exhaust gas boiler the total heat capacity and steam capacity of exhaust gas boiler increases. The increase of exhaust gas boiler heat capacity is proportional to the growth of its overall dimensions. A direct-flow design of the boiler provides a significant increase in heat efficiency and decrease in dimensions. In addition, a direct-flow boiler circuit does not need steam separator, circulation pump, the capital cost of which is about half (or even more) of heating surface cost.

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Rasmussen, C., R. E. Gallery, and J. S. Fehmi. "Passive soil heating using an inexpensive infrared mirror design – a proof of concept." SOIL 1, no. 2 (September 21, 2015): 631–39. http://dx.doi.org/10.5194/soil-1-631-2015.

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Abstract. There is a need to understand the soil system response to warming in order to model the soil process response to predicted climate change. Current methods for soil warming include expensive and difficult to implement active and passive techniques. Here we test a simple, inexpensive in situ passive soil heating approach, based on easy to construct infrared mirrors that do not require automation or enclosures. The infrared mirrors consisted of 61 × 61 cm glass panels coated with infrared reflecting film. The mirrors as constructed are effective for soil heating in environments typified by an open vegetation canopy. Mirror tests were performed on three soils of varying texture, organic matter content, and heat capacity in a warm semi-arid environment. Results indicated that the infrared mirrors yielded significant heating and drying of soil surface and shallow subsurface relative to unwarmed control treatments, and that warming and drying effects were soil specific with greater potential warming on soils with lower volumetric heat capacity. Partial shading from the mirror frame did produce periods of relative cooling at specific times of the day but overall the mirrors yielded a net soil warming. The results demonstrate proof of concept that the infrared mirrors may be used to passively heat the near soil surface, providing an inexpensive, low-maintenance alternative to other passive and active soil heating technologies.

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Kindra, V. O., E. M. Lisin, G. N. Kurdukova, and E. V. Zhigulina. "DESIGN SOLUTIONS ON THE LOW TEMPERATURE CORROSION PROBLEM FOR HEATING SURFACES OF HEAT EXCHANGERS AT GAS TURBINE CHP." Safety and Reliability of Power Industry 10, no. 4 (January 1, 2017): 316–21. http://dx.doi.org/10.24223/1999-5555-2017-10-4-316-321.

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Li, Jin Yang, Jian Li, Qing Yu Liu, and Hao Zheng. "Design of the Solar Energy-Heated Biogas Digester." Advanced Materials Research 953-954 (June 2014): 103–6. http://dx.doi.org/10.4028/www.scientific.net/amr.953-954.103.

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Heating biogas digester is essential in northern China, especially during the winter. Solar energy-heated biogas digester is a facility that radiates heat by the solar thermal, which maintains the temperature of the biogas digester. The working principle behind this facility is the division of the traditional biogas digester into three parts, namely, raw material storage section, biogas slurry storage section, and anaerobic digestion section. We only heat the anaerobic digestion section to decrease the heating volume and reduce the heat dissipating surface, thereby saving energy. Solar energy is unstable, and the anaerobic digestion section needs to be maintained at its best temperature, thus, we control the raw material inlet at its optimum temperature. This biogas digester improves the anaerobic digestion condition and enhances gas production rate, which enables the efficient function of the digester during winter.

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Li, Yipeng, Ningning Gong, Yaohui Wang, Yuntao Chen, Bowen Wang, and Xiping Li. "Advances in Polymer Technology Application of Pareto-Based Genetic Algorithm in Determining Layout of Heating Rods for a Plastic Injection Mold." Advances in Polymer Technology 2020 (March 21, 2020): 1–7. http://dx.doi.org/10.1155/2020/7573693.

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The Pareto-based genetic algorithm is an effective way to solve complex optimization design problems in engineering. In this study, first, the principles of Pareto optimal solutions and multiobjective genetic algorithm were presented. Second, to investigate the influence of the mold temperature on the products’ performances, a multicavity experiment injection mold was designed whose temperature could be controlled by the heating rods. To obtain a homogeneous temperature distribution across the multicavity surfaces after the heating stage, multiobjective optimization models for the heating rods layout were established based on the heat transfer process of the mold. Finally, the Pareto-based genetic algorithm and finite element method were combined to solve the optimized models to obtain the optimal solution. After a finite element analysis and experimental injection, it is proved that the optimized distribution of the heating rods in the mold is necessary for the experiment and production.

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Shtuts, Andrii, and Maxim Sluzalyuk. "RESEARCH OF PUNCHING PROCESSES BY PACKING WITH USE OF SURFACE HEATING OF PREPARATIONS." Vibrations in engineering and technology, no. 2(97) (August 27, 2020): 138–48. http://dx.doi.org/10.37128/2306-8744-2020-2-15.

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Despite the fact that stamping processes have been around for a relatively long time and have significant advantages compared to traditional approaches, as well as high technical and economic indicators, this process is not widespread. The machine-building industry needs mass production and use of sophisticated parts of various designs. The need of Ukraine for the details of such a design varies significantly and can reach tens of millions of pieces. The need for ring blanks of type flanges (gear) of the total amount is more than 50% [1]. According to foreign enterprises, when cutting, the material utilization ratio is 40-50%, and when using stamping, it is pumped through using surface heating of workpieces - 75-80% [5]. If we take into account the use of energy for the production of steel and its processing per unit weight of the finished part, then it is 70–84 MJ / kg when machined, and 41–49 MJ / kg for plastic deformation. To improve the ductility and deformability of the material, it is advisable to use induction plants for heating carbon steel preforms before pressure treatment. Two types of fundamentally different heating options are used: pass-through, when the workpiece warms up to its entire thickness with a temperature difference between the surface and the core of 50-100 °, and surface, when you need to heat only a relatively small layer of metal to a certain depth. Before stamping, wetting requires the use of surface induction heating, which provides greater surface plasticity of the workpiece material without changing its structure [3]. In this regard, surface and end-to-end inductive heating installations are widely used in stamping processes for wetting. The absence of theoretically justified parameters of the regime leads to the use in practice of induction heating of systems with unsuccessful design solutions and relatively low technical and economic indicators. Thus, there is a need for relevant research aimed at determining the rational parameters of the heating mode, providing on this basis effective processing of workpieces.

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Fong, K. F., T. T. Chow, and V. I. Hanby. "Development of Optimal Design of Solar Water Heating System by Using Evolutionary Algorithm." Journal of Solar Energy Engineering 129, no. 4 (September 27, 2006): 499–501. http://dx.doi.org/10.1115/1.2770758.

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There are growing initiatives to promote renewable energy in Hong Kong, particularly for solar energy. In order to encourage wider application of centralized solar water heating system for high-rise residential buildings, it is important to pursue an optimal design to get significant energy-savings potential. In this regard, system optimization would be useful because it can relate to a number of design variables of the solar water heating system. The objective function is to maximize the year-round energy savings by using the solar heating against the conventional domestic electric heating. For the methodology of optimization, evolutionary programming, one of the paradigms of the evolutionary algorithm, was applied. From the optimization results, it is suggested that the solar collectors can be installed onto the external shading devices as an integrated architectural feature, since the optimal tilt angle is 21 deg and relatively flat. The optimal surface azimuth is southwest 16 deg, instead of due south. For the engineering design, both the optimal values of calorifier storage capacity and pump flow rate show that the calculations from normal design practice may not achieve an optimal performance.

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Aksenov, Andrey. "Heat transfer from the collective finning of pipes in heat exchangers under asymmetric boundary conditions." E3S Web of Conferences 91 (2019): 02009. http://dx.doi.org/10.1051/e3sconf/20199102009.

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The solution of the problem of the heat flux from the surface of collective finning at various temperatures of its ends is given. The obtained analytical formulas allow giving a quantitative estimate of the influence of the asymmetry of the boundary conditions on the heat transfer through the finned heat exchange surface. Calculated dependencies can be used in the design of high-efficiency heat exchangers for air conditioning, ventilation, and heating systems. The presented results can be especially useful under real operating conditions of heat exchange surfaces. This, in turn, ensures the safe and reliable operation of the building’s engineering systems as a whole.

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Tovar, Santiago, Cesar A. Hernández, and Johann F. Osma. "Design, Simulation, and Fabrication of a Copper–Chrome-Based Glass Heater Integrated into a PMMA Microfluidic System." Micromachines 12, no. 9 (September 2, 2021): 1067. http://dx.doi.org/10.3390/mi12091067.

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In this paper, the development of a copper–chrome-based glass microheater and its integration into a Polymethylmethacrylate (PMMA) microfluidic system are presented. The process highlights the importance of an appropriate characterization, taking advantage of computer-simulated physical methods in the heat transfer process. The presented system architecture allows the integration for the development of a thermal flow sensor, in which the fluid flows through a 1 mm width × 1 mm length microchannel across a 5 mm width × 13 mm length heating surface. Using an electrothermal analysis, based on a simulation and design process, the surface heating behavior curve was analyzed to choose a heating reference point, primarily used to control the temperature point within the fluidic microsystem. The heater was characterized using the theory of electrical instrumentation, with a 7.22% error for the heating characterization and a 5.42% error for the power consumption, measured at 0.69 W at a temperature of 70 °C. Further tests, at a temperature of 115 °C, were used to observe the effects of the heat transfer through convection on the fluid and the heater surface for different flow rates, which can be used for the development of thermal flowmeters using the configuration presented in this work.

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Khan, Pathan Fayaz, S. Sengottuvel, Rajesh Patel, K. Gireesan, R. Baskaran, and Awadhesh Mani. "Design and Implementation of a Discrete-Time Proportional Integral (PI) Controller for the Temperature Control of a Heating Pad." SLAS TECHNOLOGY: Translating Life Sciences Innovation 23, no. 6 (May 10, 2018): 614–23. http://dx.doi.org/10.1177/2472630318773697.

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Contact heat evoked potentials (CHEPs) are recorded from the brain by giving thermal stimulations through heating pads kept on the surface of the skin. CHEP signals have crucial diagnostic implications in human pain activation studies. This work proposes a novel design of a digital proportional integral (PI) controller based on Arduino microcontroller with a view to explore the suitability of an electric heating pad for use as a thermode in a custom-made, cost-effective CHEP stimulator. The purpose of PI controller is to set, regulate, and deliver desired temperatures on the surface of the heating pad in a user-defined pattern. The transfer function of the heating system has been deduced using the parametric system identification method, and the design parameters of the controller have been identified using the root locus technique. The efficiency of the proposed PI controller in circumventing the well-known integrator windup problem (error in the integral term builds excessively, leading to large transients in the controller output) in tracking the reference input and the controller effort (CE) in rejecting output disturbances to maintain the set temperature of the heating pad have been found to be superior compared with the conventional PI controller and two of the existing anti-windup models.

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Kria, Fatma, Moez Hammami, and Mounir Baccar. "A modeling study on the effect of operating parameters on RHCM process using split flow channels design." Mechanics & Industry 20, no. 5 (2019): 503. http://dx.doi.org/10.1051/meca/2019024.

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In this work, a three-dimensional numerical study of thermal behavior of RHCM mold for automotive parts production was undertaken. Particularly, simulation of several heating/cooling cycles was conducted to determine, at the regular cyclic regime, thermal behaviors at cavity/core plates and polymer as well as thermal and hydrodynamic behaviors at cooling water. It was demonstrated that heating/cooling channels with split flow design are suitable for RHCM regulation. Besides, to further promote part quality, process productivity, and profitability, the effect of cooling parameters, such as the coolant temperature and flow velocity in channels, on the RHCM process efficiency was analyzed. To highlight the influence of these parameters on the productivity and profitability of the process, the cycle time and the consumed energy were used. Temperature gap at the cavity plate surfaces after the heating phase as well as the maximum temperature difference (MTD) in the polymer part after the cooling phase were used as criteria to evaluate the automotive part quality. The results show that the coolant temperature increase in the range between 30 and 60 °C reduces the energy consumption and improves the finished product quality with almost the same cycle time obtained by low coolant temperature. As regards to coolant flow velocity effect, an optimum value of about 1 m.s−1 improves part quality and provides a compromise between the cycle time and process profitability.

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Timans, Paul J. "A Short History of Pattern Effects in Thermal Processing." Materials Science Forum 573-574 (March 2008): 355–74. http://dx.doi.org/10.4028/www.scientific.net/msf.573-574.355.

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Radiant energy sources enable rapid and controllable thermal processing of wafers with closed-loop control of wafer temperature. However the use of energy sources that are not in thermal equilibrium with the wafers makes the heating process sensitive to the optical properties of the wafers. In particular, patterns on wafer surfaces can cause temperature non-uniformity at length scales where lateral thermal conduction cannot smooth out the effect. Such “pattern effects” are even more significant for advanced processing techniques like millisecond annealing and pulsed laser annealing, because of the extremely large heating powers employed. The issue of pattern effects was recognized early on in the development of radiant heating technology, but has recently become a critical issue for process control. Despite the challenges, many counter-measures can be deployed to minimize pattern effects, including modifications to the wafer design, changes in processing recipe and equipment configuration. Such solutions have enabled the use of radiant heating for even the most demanding device fabrication applications.

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Li, M., R. Z. Wang, F. Yun, F. Shi, L. L. Wang, and H. L. Luo. "An Effective Flat Plate Solar Heating and Cooling Hybrid System." Adsorption Science & Technology 21, no. 5 (June 2003): 487–99. http://dx.doi.org/10.1260/026361703769645816.

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Based on the achievements of solar solid adsorption refrigeration research, a new hybrid heating and cooling system, related to the solar water heater technique, has been proposed. The conversion and utilization of solar energy for cooling and heating are also analyzed. Experiments on a prototype have shown that both the available (residual) and adsorption heats of the adsorbent bed can be recovered efficiently and simply. The results of some simulations of this new flat plate under real solar radiation are given, as well as comparisons with our previous research work. The successful design and assessment of this new flat plate hybrid system should accelerate the practical application of solid adsorption refrigeration driven by solar energy.

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Journal articles on the topic 'Design of heating surfaces'

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