Journal articles: 'Passive thermal control'

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TSUTSUI, Fumiya, Toshiyuki SHISHIDO, Tatsuya SATO, Hiroyoshi ONO, and Kentaro SHOJI. "Passive Thermal Control of Pressurized Modules of JEM." Proceedings of the JSME annual meeting 2000.4 (2000): 543–44. http://dx.doi.org/10.1299/jsmemecjo.2000.4.0_543.

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Venneri, Paolo F., Michael Eades, and Yonghee Kim. "Passive Reactivity Control of Nuclear Thermal Propulsion Reactors." Nuclear Technology 197, no. 1 (January 2, 2017): 64–74. http://dx.doi.org/10.13182/nt16-80.

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Omar, M., and Y. Zhou. "Automotive Production Control, Using Thermal Vision Systems – A Passive Thermal Imagery for Process Control." SAE International Journal of Materials and Manufacturing 1, no. 1 (April 14, 2008): 279–84. http://dx.doi.org/10.4271/2008-01-0681.

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Aggogeri, Francesco, Alberto Borboni, Angelo Merlo, and Nicola Pellegrini. "Machine Tools Thermostabilization Using Passive Control Strategies." Advanced Materials Research 590 (November 2012): 252–57. http://dx.doi.org/10.4028/www.scientific.net/amr.590.252.

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The aim of this study is to investigate passive control strategies using Phase Change Materials in Machine Tools (MTs) thermostabilization. By considering the main issues related to the thermal stability, authors presented the application of novel multifunctional materials to Machine Tools structures. A set of advanced materials are considered: aluminium foams, corrugate-core sandwich panels and polymeric concrete beds. The adopted solutions have been infiltrated by phase change materials (PCMs) in order to maintain the thermal stability of MTs when the environmental temperature is perturbed. The paper shows the results of simulative and experimental tests.

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Bivolarova, Mariya, Arsen Melikov, Tereza Snaselova, and Chong Shen. "Passive Control Of The Bed Micro-Environment By Quilts." E3S Web of Conferences 111 (2019): 02064. http://dx.doi.org/10.1051/e3sconf/201911102064.

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An easy method to passively control the bed micro-environment and thus thermal comfort of people is to use a cover with appropriate thermal insulation. The purpose of this study was to find out the potential of generating uniform and non-uniform bed thermal micro-environment with quilts. The effect of the thermal resistance of quilts on the temperature field in the bed and dry heat loss of a human body was studied. Thermal manikin was used to resemble person in bed. Four quilts with different properties such as weight and non-uniform filling and type of filling material (Muscovy down and polyester fibre) were studied. Full-scale experiments were conducted in a ventilated climate chamber under four thermal conditions including two levels of relative humidity (50% and 70%) and two air temperatures (15ᵒC and 20ᵒC). The dry heat loss of the thermal manikin was higher with polyester fibre quilt than with quilt having the same weight but with Muscovy down filling. This was obtained under all tested room conditions. The studied non-uniformity in down distribution of the quilt provided similar thermal insulation on the feet and chest.

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Budnik, S. A., A. N. Nenarokomov, and D. M. Titov. "Investigation of Passive Systems for Thermal Control of Spacecraft." Journal of Engineering Physics and Thermophysics 91, no. 6 (November 2018): 1565–72. http://dx.doi.org/10.1007/s10891-018-1894-9.

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Kenisarin, Murat, and Khamid Mahkamov. "Passive thermal control in residential buildings using phase change materials." Renewable and Sustainable Energy Reviews 55 (March 2016): 371–98. http://dx.doi.org/10.1016/j.rser.2015.10.128.

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Cheng, Sun, Liu, Liu, Li, Li, and Hu. "Engineering Design of an Active–Passive Combined Thermal Control Technology for an Aerial Optoelectronic Platform." Sensors 19, no. 23 (November 28, 2019): 5241. http://dx.doi.org/10.3390/s19235241.

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: In order to ensure the imaging performance of the aerial optoelectronic platform system in low temperature environment, an active-passive combined thermal control technology was studied. A thermal control finite element model of the aerial optoelectronic platform was established. Additionally, thermal control simulation analysis and experiments under extreme conditions were carried out respectively. The simulation and experimental results showed that the temperature level of the primary mirror is improved above 25 ℃ by the proposed thermal control technology effectively, meanwhile the temperature gradient of the primary and secondary mirrors are less than 5 ℃. The successful implementation of this active-passive combined thermal control technology provides a technical support for the precision thermal control of aerial optoelectronic platforms.

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Fořt, Jan, Jan Kočí, Jaroslav Pokorný, Luboš Podolka, Michal Kraus, and Robert Černý. "Characterization of Responsive Plasters for Passive Moisture and Temperature Control." Applied Sciences 10, no. 24 (December 20, 2020): 9116. http://dx.doi.org/10.3390/app10249116.

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Ambient comfort maintenance accompanied by excessive energy consumption is hugely criticized concerning the limited sustainability of the building sector in the long-term. In this sense, the energy reduction strategies based on the employment of passive air-control techniques are viewed as a prospective solution for improved energy performance. In order to contribute to this significant issue, this paper is aimed at the design and material characterization of novel plaster with an improved thermal and humidity control performance. For this purpose, a form-stable diatomite/dodecanol-based phase change material together with superabsorbent polymer are used as admixtures for the passive moderation of indoor air quality by newly designed modified plasters. The experimental assessment of the functional properties by means of mechanical strength, thermal conductivity, and hygric properties is performed. Considering the goal of the paper, particular attention is paid to the characterization of water vapor storage and moisture buffering according to the Nordtest method. Differential scanning calorimetry is employed for the description of phase change intervals as well as the specific enthalpy of phase change. The obtained results point to significant improvements in the hygroscopic performance and increased thermal energy storage that can be used for passive moderation of the indoor temperature and reduction of the relative humidity swings.

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YOSHINO, Hiroshi, and Ken AOZASA. "MEASUREMENT ON THERMAL ENVIRONMENT OF THE ATRIUM WITH PASSIVE CONTROL SYSTEM." AIJ Journal of Technology and Design 2, no. 3 (1996): 207–10. http://dx.doi.org/10.3130/aijt.2.207.

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Han, Yanlong, Weiling Luan, Yifeng Jiang, and Xiaoni Zhang. "Protection of electronic devices on nuclear rescue robot: Passive thermal control." Applied Thermal Engineering 101 (May 2016): 224–30. http://dx.doi.org/10.1016/j.applthermaleng.2016.02.116.

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Henze, Gregor P., Clemens Felsmann, and Gottfried Knabe. "Evaluation of optimal control for active and passive building thermal storage." International Journal of Thermal Sciences 43, no. 2 (February 2004): 173–83. http://dx.doi.org/10.1016/j.ijthermalsci.2003.06.001.

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Massaguer Colomer, Albert, Eduard Massaguer, Toni Pujol, Martí Comamala, Lino Montoro, and J. R. González. "Electrically tunable thermal conductivity in thermoelectric materials: Active and passive control." Applied Energy 154 (September 2015): 709–17. http://dx.doi.org/10.1016/j.apenergy.2015.05.067.

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Snášelová, Tereza, Mariya Petrova Bivolarova, and Arsen Krikor Melikov. "Passive control of the bed micro-environment by using naturally ventilated mattress." E3S Web of Conferences 111 (2019): 02042. http://dx.doi.org/10.1051/e3sconf/201911102042.

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Proper sleep is of a big importance considering that people spend one third of their lives sleeping. Thermal conditions and indoor air quality have an impact on sleep and thus must be optimized and controlled to enhance sleep quality. However, changing the thermal environment in the whole bedroom is not efficient, because of unnecessary use of energy and slow response of the HVAC system. Control of the bed microclimate is a quick and efficient way to obtain optimal conditions. Passive methods of control may, in a simple and inexpensive way, create comfortable and beneficial conditions for sleep. The performance of a porous mattress from highly-breathable material was investigated to validate the hypothesis that the natural ventilation it generates improves thermal and humidity conditions in bed. A simple method using a wet cloth was used to simulate sweating on the surface of a thermal manikin resembling a person in bed. The results showed promising effect of the breathable material on improving thermal and humidity conditions in bed, especially when it was used without textile cover. However, the mattress together with its original textile cover did not provide any significant ventilation effect, neither on humidity conditions in the bed, nor on cooling of the manikin’s body.

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Карпов, Д., and Denis Karpov. "THE ACTIVE METHOD OF CONTROL THE THERMAL CONDUCTIVITY OF BUILDING MATERIALS AND PRODUCTS." Bulletin of Belgorod State Technological University named after. V. G. Shukhov 4, no. 7 (July 21, 2019): 57–62. http://dx.doi.org/10.34031/article_5d35d0b79c34c5.75173950.

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Thermal control refers to non-destructive testing methods. There are passive and active thermal non-destructive testing. With passive thermal control, the test object is characterized by a temperature field formed during its operation. With active thermal control, an additional source of thermal stimulation of the controlled object is used. Thermal control is widely used in various sectors of construction, energy, engineering and transport. The paper proposes a variant of active thermal non-destructive control of thermal conductivity coefficient of building materials and products on the example of a fragment of a building structure made of silicate bricks. The controlled object is subjected to thermal stimulation by an external source of thermal energy until the fixed thermal regime. Thermography of the test object surfaces is performed. The average values of surfaces temperature or individual sections of controlled object are calculated. The heat equation determines a controlled parameter - the heat coefficient of the object under control. The thermal resistance (heat transfer resistance) of the controlled object is calculated with a known coefficient of thermal conductivity. The heat transfer coefficient is calculated with a known coefficient of thermal resistance (heat transfer resistance). The method is implemented in the laboratory. It can be used in field and operating conditions for accurate and rapid determination of the key thermal properties of building materials and products.

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Henze, Gregor P. "Energy and Cost Minimal Control of Active and Passive Building Thermal Storage Inventory." Journal of Solar Energy Engineering 127, no. 3 (January 21, 2005): 343–51. http://dx.doi.org/10.1115/1.1877513.

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In contrast to building energy conversion equipment, less improvement has been achieved in thermal energy distribution, storage and control systems in terms of energy efficiency and peak load reduction potential. Cooling of commercial buildings contributes significantly to the peak demand placed on an electrical utility grid and time-of-use electricity rates are designed to encourage shifting of electrical loads to off-peak periods at night and on weekends. Buildings can respond to these pricing signals by shifting cooling-related thermal loads either by precooling the building’s massive structure (passive storage) or by using active thermal energy storage systems such as ice storage. Recent theoretical and experimental work showed that the simultaneous utilization of active and passive building thermal storage inventory can save significant amounts of utility costs to the building operator, yet increased electrical energy consumption may result. The article investigates the relationship between cost savings and energy consumption associated with conventional control, minimal cost and minimal energy control, while accounting for variations in fan power consumption, chiller capacity, chiller coefficient-of-performance, and part-load performance. The model-based predictive building controller is employed to either minimize electricity cost including a target demand charge or electrical energy consumption. This work shows that buildings can be operated in a demand-responsive fashion to substantially reduce utility costs with marginal increases in overall energy consumption. In the case of energy optimal control, the reference control was replicated, i.e., if only energy consumption is of concern, neither active nor passive building thermal storage should be utilized. On the other hand, cost optimal control suggests strongly utilizing both thermal storage inventories.

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Thanarasi, Karthigesu. "Thermal Analysis of CUBESAT in Worse Case Hot and Cold Environment Using FEA Method." Applied Mechanics and Materials 225 (November 2012): 497–502. http://dx.doi.org/10.4028/www.scientific.net/amm.225.497.

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One of the necessary parts of CubeSat’s design is the thermal analysis. It will provide the operating temperatures and their distribution for all devices inside the CubeSat. For decision, which temperature standard can be used for components it is necessary to know the maximum and the minimum value of the temperature. In virtue of these results the position of the all devices must be also optimized. Some methods of the thermal control are also proposed. Contrary to most subsystems the thermal subsystem is not independent of the others. All elements in the spacecraft have an influence on the thermal housekeeping by either emitting or absorbing energy or both respectively. The objective of thermal subsystem is to ensure that the spacecraft operate within the spacecraft operating temperature range. There are two types of thermal control technique; passive and active. Due to the size and power constraint of CubeSat, passive thermal control will be more suitable but analysis must be done in order to know that passive control is sufficient. The FEA methodology would be utilized in order to determine the spacecraft operating temperature within the range. To accomplish this, MSC Nastran Patran software will be used as the FEA modeling tool. The MD Patran will act as preprocessing tool whereas MD Nastran will act as post processing tool. If the simulated thermal range is deviates, temperature sensors and heaters will be mounted on the CubeSat to monitor the deviation. Alternatively, mounting Kapton tape onto the CubeSat structure and laying gold coating would be another method to maintain the desired temperature range. The design of the thermal system shall be based on passive methods. This approach is vital to avoid power consumption in cases where it would not be necessary. As conclusion the thermal subsystem is designed to operate the spacecraft throughout its mission phases without any failure.

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Zhou, Guo, Moncef Krarti, and Gregor P. Henze. "Parametric Analysis of Active and Passive Building Thermal Storage Utilization*." Journal of Solar Energy Engineering 127, no. 1 (February 1, 2005): 37–46. http://dx.doi.org/10.1115/1.1824110.

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Cooling of commercial buildings contributes significantly to the peak demand placed on an electrical utility grid. Time-of-use electricity rates encourage shifting of electrical loads to off-peak periods at night and on weekends. Buildings can respond to these pricing signals by shifting cooling-related thermal loads either by precooling the building’s massive structure or by using active thermal energy storage systems such as ice storage. While these two thermal batteries have been engaged separately in the past, this paper investigates the merits of harnessing both storage media concurrently in the context of optimal control for a range of selected parameters. A parametric analysis was conducted utilizing an EnergyPlus-based simulation environment to assess the effects of building mass, electrical utility rates, season and location, economizer operation, central plant size, and thermal comfort. The findings reveal that the cooling-related on-peak electrical demand and utility cost of commercial buildings can be substantially reduced by harnessing both thermal storage inventories using optimal control for a wide range of conditions.

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Riehl, Roger R. "UTILIZATION OF PASSIVE THERMAL CONTROL TECHNOLOGIES IN COOLING ELECTRONICS: A BRIEF REVIEW." Heat Pipe Science and Technology, An International Journal 7, no. 3-4 (2016): 161–83. http://dx.doi.org/10.1615/heatpipescietech.2017017791.

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Scherbakov, Alexander, Daria Monastyreva, and Vitaly Smirnov. "Passive fluxgate control of structural transformations in structural steels during thermal cycling." E3S Web of Conferences 135 (2019): 03022. http://dx.doi.org/10.1051/e3sconf/201913503022.

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Thermocycler processing (TCO) of metals and alloys belongs to one of the most effective ways to obtain the structure of structural steels with a given degree of dispersion. However, the development of thermocycler processing modes in each case is individual in nature and cannot be mechanically transferred from one material to another. Therefore, it is necessary to consider the structural changes in metals during TCO using examples of steels belonging to different groups so that from the whole variety of processes, dissolution and precipitation of phases, stresses and strains, only those that allow you to obtain a given optimal fine-grained structure are selected. Based on the obtained data, we plotted the dependence of the magnetic field strength Hp on the number of cycles during thermal cycling. A comparative analysis of the obtained results is made and conclusions are drawn on the relationship between the magnetic parameter Hp and structural changes in steels during TCO.

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Krishnan, Shankar, Jayathi Y. Murthy, and Suresh V. Garimella. "A Two-Temperature Model for the Analysis of Passive Thermal Control Systems." Journal of Heat Transfer 126, no. 4 (2004): 628. http://dx.doi.org/10.1115/1.1773194.

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Appourchaux, Thierry P. "Passive thermal control of a multilayer filter for space-based solar observations." Optical Engineering 31, no. 8 (1992): 1715. http://dx.doi.org/10.1117/12.58714.

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Tauber, Shachar, John Bowman, Joe Bango, and Randall Fuerst. "Precise Temperature Control of Donor Cornea Tissue With Reusable Passive Thermal Container." Cornea 30, no. 9 (September 2011): 977–82. http://dx.doi.org/10.1097/ico.0b013e318206862a.

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Jones, C. A., K. E. David, R. J. LeVesque, and H. W. Babel. "Environmental effects on passive thermal control materials of the space station freedom." Acta Astronautica 34 (October 1994): 91–100. http://dx.doi.org/10.1016/0094-5765(94)90247-x.

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Tiwari, G. N., M. Upadhyay, and S. N. Rai. "Thermal control of a passive solar apartment under active mode of operation." Energy Conversion and Management 34, no. 1 (January 1993): 51–61. http://dx.doi.org/10.1016/0196-8904(93)90007-w.

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Wu, Xueyu, Le Yuan, Xiaolong Weng, Lun Qi, Biao Wei, and Wentao He. "Passive Smart Thermal Control Coatings Incorporating CaF2/VO2 Core–Shell Microsphere Structures." Nano Letters 21, no. 9 (April 29, 2021): 3908–14. http://dx.doi.org/10.1021/acs.nanolett.1c00454.

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Ullah, Ikram, Sayed Shah, Gul Zaman, Taseer Muhammad, and Zakir Hussain. "Passive control of magneto-nanomaterials transient flow subject to non-linear thermal radiation." Thermal Science, no. 00 (2021): 169. http://dx.doi.org/10.2298/tsci201015169u.

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Present investigation is concerned with mixed convection flow of Williamson nanoliquid over an unsteady slandering stretching sheet. Aspects of non-linear thermal radiation, Brownian diffusion and thermophoresis effects are addressed. Non-linear stretching surface of varying thickness induce the flow. Novel features of combined zero mass flux and convective conditions are accounted. Use of appropriate transformations results into the non-linear ODEs. Computations for the convergent solutions are provided. Graphs are designed for interpretations to quantities. Nusselt number and surface drag are computationally inspected. Our computed results indicate that attributes of nanoparticles and non-linear thermal radiation enhance the temperature distribution.

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Karpov, Denis, Mikhail Pavlov, Liliya Mukhametova, and Anton A. Mikhin. "Features and results of assessment the thermal conductivity of building materials and products by the active method of thermal non-destructive testing." E3S Web of Conferences 220 (2020): 01053. http://dx.doi.org/10.1051/e3sconf/202022001053.

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Thermal control (passive and active) is a non-destructive testing method. During passive thermal control, the test object is characterized by a temperature field formed during its operation. In active thermal control, the test object is additionally thermally stimulated. This technique is widely used in various areas of construction, energy, mechanical engineering, transport. This paper proposes a variant of active thermal non-destructive assessment of the thermal conductivity coefficient of building materials and products on the example of a fragment of a building structure made of silicate bricks. The test object is subjected to thermal stimulation by an external source of thermal energy before reaching a steady-state thermal regime. Thermography of the test object surfaces is carried out. The average integral temperatures of surfaces or individual sections of the test object are calculated. The coefficient of thermal conductivity of the test object is determined, which is used to calculate its thermal resistance (resistance to heat transfer). After that, the coefficient of heat transfer is calculated. The method was implemented in laboratory conditions. It can be used in natural and operational conditions for accurate and quick determination of the key thermophysical properties of building materials and products.

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Weng, Kui, Fanlin Meng, and Monjur Mourshed. "Model-Based Optimal Control of Window Openings for Thermal Comfort." Proceedings 2, no. 15 (August 27, 2018): 1134. http://dx.doi.org/10.3390/proceedings2151134.

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Passive cooling via natural ventilation through window openings is a low-carbon strategy to minimize cooling demand and to adapt to the rising ambient temperatures due to climate change. However, relying on the manual control of windows by occupants is not always optimal for maintaining indoor thermal comfort. In this study, a model-based approach using dynamic thermal simulation program EnergyPlus is used for the optimal control of window openings to maintain indoor thermal comfort. Based on the day-ahead weather forecast, the window opening schedule for the next 24 h is optimized through iteration. Results indicate that the proposed optimal control method significantly improves indoor thermal comfort than using some most commonly used manual control and automated control based on hourly set-point and outdoor temperatures.

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Riehl, Roger R. "ADVANCED TWO-PHASE PASSIVE THERMAL CONTROL DEVICES: LOOP HEAT PIPES AND PULSATING HEAT PIPES." Revista de Engenharia Térmica 5, no. 1 (July 31, 2006): 54. http://dx.doi.org/10.5380/reterm.v5i1.61661.

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This paper presents the development of two-phase passive thermal control devices that can be used at both ground and space applications. These devices operate by acquiring heat through their evaporation section and rejecting through their condensation section, keeping a tight control on the heat source temperature without the presence of moving parts. Recent researches with loop heat pipes (LHPs) have showed the great capability of such a device in managing high levels of heat while keeping the source temperature within certain levels. For this case, experimental tests of a LHP are presented, where the behavior related to its operation with power cycles can be evaluated and its performance can be verified. This paper also presents an investigation of a two-phase thermal control device called pulsating heat pipe (PHP) configured as an open loop. Experimental tests with different working fluids are presented, which shows the great capability of the PHP in operating at both horizontal and vertical orientations and promoting the thermal control, which is highly affected by the working fluid and geometric parameters. The experimental results presented for both devices are intended to contribute for the continuous development of these two passive thermal control devices.

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Yang, Lin, Qiang Li, Lin Kong, Song Gu, and Lei Zhang. "Quasi-All-Passive Thermal Control System Design and On-Orbit Validation of Luojia 1-01 Satellite." Sensors 19, no. 4 (February 17, 2019): 827. http://dx.doi.org/10.3390/s19040827.

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In order to resolve the large fluctuations in temperature range problem of Luojia 1-01 satellite caused by low heat inertia and poor thermal conductivity of structure, a quasi-all-passive thermal control system (TCS) design is presented under the conditions of limited resources including mass and power consumption. The effectiveness of the TCS design is verified by both ground thermal balanced test and related telemetry data of on-orbit performance. Firstly, according to the structural features and working modes of the satellite, isothermal design was implemented and the effectiveness was verified by thermal analysis using finite element method. Secondly, based on the results of the thermal analysis, thermal design was optimized and verified by the thermal balanced test. Finally, the thermal design was proved to be effective by temperature data acquired from telemetry data of on-orbit performance, and the thermal analysis model was improved and updated based on the results of thermal balanced test and temperature data of on-orbit performance. The on-orbit data indicates that temperature of optical camera stables at about 12 °C, temperature of battery stables at 19 °C, temperature of instruments inside and outside the satellite cabin is ranging from 10 °C to 25 °C. Temperature fluctuation range of optical camera is less than 2 °C when it is not imaging. Temperature fluctuation range of instruments not facing the sun is less than 4 °C. The data suggests that the temperature level of the satellite meets general design requirements, and the quasi-all-passive TCS design of the satellite is practicable.

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Liu, Simeng, and Gregor P. Henze. "Evaluation of Reinforcement Learning for Optimal Control of Building Active and Passive Thermal Storage Inventory." Journal of Solar Energy Engineering 129, no. 2 (October 31, 2006): 215–25. http://dx.doi.org/10.1115/1.2710491.

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This paper describes an investigation of machine learning for supervisory control of active and passive thermal storage capacity in buildings. Previous studies show that the utilization of active or passive thermal storage, or both, can yield significant peak cooling load reduction and associated electrical demand and operational cost savings. In this study, a model-free learning control is investigated for the operation of electrically driven chilled water systems in heavy-mass commercial buildings. The reinforcement learning controller learns to operate the building and cooling plant based on the reinforcement feedback (monetary cost of each action, in this study) it receives for past control actions. The learning agent interacts with its environment by commanding the global zone temperature setpoints and thermal energy storage charging∕discharging rate. The controller extracts information about the environment based solely on the reinforcement signal; the controller does not contain a predictive or system model. Over time and by exploring the environment, the reinforcement learning controller establishes a statistical summary of plant operation, which is continuously updated as operation continues. The present analysis shows that learning control is a feasible methodology to find a near-optimal control strategy for exploiting the active and passive building thermal storage capacity, and also shows that the learning performance is affected by the dimensionality of the action and state space, the learning rate and several other factors. It is found that it takes a long time to learn control strategies for tasks associated with large state and action spaces.

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Mason, P. V. "Long-term performance of the passive thermal control systems of the IRAS spacecraft." Cryogenics 28, no. 2 (February 1988): 137–41. http://dx.doi.org/10.1016/0011-2275(88)90060-4.

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Orosa, José A., and Armando C. Oliveira. "Hourly indoor thermal comfort and air quality acceptance with passive climate control methods." Renewable Energy 34, no. 12 (December 2009): 2735–42. http://dx.doi.org/10.1016/j.renene.2009.04.021.

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Edelmann, Martin, Walter Baumann, Alfred Bertram, Günter Kussmaul, and Walter Väth. "Enhanced Thermal Expansion Control Rod Drive Lines for Passive Shutdown of Fast Reactors." Nuclear Technology 107, no. 1 (July 1994): 3–14. http://dx.doi.org/10.13182/nt94-a34993.

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Sun, C., Z. Y. Wang, X. Chen, and X. L. Xia. "A passive thermal control method by radiative shield with multi-parameter adjustment capacity." Applied Thermal Engineering 94 (February 2016): 600–606. http://dx.doi.org/10.1016/j.applthermaleng.2015.10.124.

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Dounis, A. I., M. J. Santamouris, and C. C. Lefas. "Implementation of artificial intelligence techniques in thermal comfort control for passive solar buildings." Energy Conversion and Management 33, no. 3 (March 1992): 175–82. http://dx.doi.org/10.1016/0196-8904(92)90123-e.

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Kim, Kyung Mo, and In Cheol Bang. "Thermal-hydraulic phenomena inside hybrid heat pipe-control rod for passive heat removal." International Journal of Heat and Mass Transfer 119 (April 2018): 472–83. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2017.11.138.

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Liu, Tao, Chong Wang, Yi Yu, Zhenyu Liu, and Fengyun He. "Passive Athermal Optical Design Method Considering Thermal-Induced Surface Deformation." Photonics 8, no. 9 (September 16, 2021): 396. http://dx.doi.org/10.3390/photonics8090396.

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Temperature variation not only results in changes in refractive index, radius, thickness, and air space, but also leads to surface deformation due to the mismatch in thermal expansion coefficients between glass and mechanical materials. However, existing passive athermal optical design methods cannot optimize thermal-induced surface deformation, and optimization methods usually focus on structural optimization or thermal control rather than optical optimization. Here, we investigate the deterioration in image quality caused by thermal-induced surface deformation and propose a passive athermal optical design method to reduce deterioration. To this end, MATLAB was utilized to jointly call finite element analysis (FEA) software (COMSOL) and optical design software (Code V) to realize the data exchange of an optical–mechanical–thermal integrated analysis for iterative optical optimization. This process makes automatic iterative optimization possible by transforming parametric FEA results into Zernike coefficients in each iteration of optimization. The theoretical and design examples indicate that our method can effectively reduce the degradation in image quality with surface deformation. Our method provides an optical optimization approach for optical designers to work on a passive athermal optical design by considering thermal-induced surface deformation.

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Almao de Herrera, Nastia, and Jose Rincon. "Alternative Designs for Passive Cooling of Homes for Venezuela." Journal of Solar Energy Engineering 115, no. 3 (August 1, 1993): 161–68. http://dx.doi.org/10.1115/1.2930044.

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A two-dimensional model has been applied to predict the indoor temperature fluctuations of a building using a finite difference technique based on the control volume approach and the “SIMPLE” algorithm. The model simulates thermal performance of a rectangular section where inside air motion by free convection and unsteady heat conduction through walls and roof, are allowed. Since it is a two-dimensional model and only the thermal load through external surfaces is considered, numerical results allow one first to study qualitative performance of a rectangular building section and, secondly, to make quantitative comparisons among alternative designs. In order to show the usefulness of the model, eight design cases were simulated under the transient climatic conditions of Maracaibo (latitude = 10° 30′; longitude = 71° 36′), a hot and humid region in Venezuela. Numerical results show how thermal load through external surfaces can be reduced 60 percent and over in relation to the highest thermal load case.

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Behi, Hamidreza, Danial Karimi, Rekabra Youssef, Mahesh Suresh Patil, Joeri Van Mierlo, and Maitane Berecibar. "Comprehensive Passive Thermal Management Systems for Electric Vehicles." Energies 14, no. 13 (June 28, 2021): 3881. http://dx.doi.org/10.3390/en14133881.

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Lithium-ion (Li-ion) batteries have emerged as a promising energy source for electric vehicle (EV) applications owing to the solution offered by their high power, high specific energy, no memory effect, and their excellent durability. However, they generate a large amount of heat, particularly during the fast discharge process. Therefore, a suitable thermal management system (TMS) is necessary to guarantee their performance, efficiency, capacity, safety, and lifetime. This study investigates the thermal performance of different passive cooling systems for the LTO Li-ion battery cell/module with the application of natural convection, aluminum (Al) mesh, copper (Cu) mesh, phase change material (PCM), and PCM-graphite. Experimental results show the average temperature of the cell, due to natural convection, Al mesh, Cu mesh, PCM, and PCM-graphite compared with the lack of natural convection decrease by 6.4%, 7.4%, 8.8%, 30%, and 39.3%, respectively. In addition, some numerical simulations and investigations are solved by COMSOL Multiphysics®, for the battery module consisting of 30 cells, which is cooled by PCM and PCM-graphite. The maximum temperature of the battery module compared with the natural convection case study is reduced by 15.1% and 17.3%, respectively. Moreover, increasing the cell spacing in the battery module has a direct effect on temperature reduction.

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Henze, Gregor P., Thoi H. Le, Anthony R. Florita, and Clemens Felsmann. "Sensitivity Analysis of Optimal Building Thermal Mass Control." Journal of Solar Energy Engineering 129, no. 4 (May 19, 2006): 473–85. http://dx.doi.org/10.1115/1.2770755.

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In order to avoid high utility demand charges from cooling during the summer and to level a building’s electrical demand profile, precooling of the building’s massive structure can be applied to shift cooling-related thermal loads in response to utility pricing signals. Several previous simulation and experimental studies have shown that proper precooling can attain considerable reduction of operating cost in buildings. This paper systematically evaluates the merits of the passive building thermal capacitance to minimize energy cost for a design day using optimal control. The evaluation is conducted by means of a sensitivity analysis utilizing a dynamic building energy simulation program coupled to a popular technical computing environment. The optimal controller predicts the required extent of precooling (zone temperature set-point depression), depending on the utility rate structure, occupancy and on-peak period duration and onset, internal gains, building mass, occupancy period temperature set-point range, and weather as characterized by diurnal temperature and relative humidity swings. In addition to quantifying the building response, energy consumption, and utility cost, this paper extracts the dominant features of the optimal precooling strategies for each of the investigated cases so that guidelines for near-optimal building thermal mass savings may be developed in the future.

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Karpov, Denis, Daniya Zaripova, and Mikhail Pavlov. "Feasibility of active and passive thermal control application for defect identification of building materials and products, enclosures of construction objects." E3S Web of Conferences 288 (2021): 01101. http://dx.doi.org/10.1051/e3sconf/202128801101.

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This paper considers one of the most promising and modern methods of non-destructive testing - thermal control. The possibilities and advantages of thermal control for identifying defects of various building materials and products, enclosures of buildings and structures are presented. Brief characteristics of the main defects of building materials, products, and structures are presented. The basic principles of identifying hidden (invisible) and explicit (visible) defects are briefly considered and the practical results of construction defect identification of objects for various purposes using thermal imaging equipment are presented. The zones of thermal temperature anomalies are localized during qualitative analysis of thermograms (the method of active thermal control). The considered example is a fragment of a building enclosure made ceramic bricks with artificially created technical defects. For some enclosures of building structures and constructions, explicit thermal defects were identified from thermal imaging, their qualitative analysis was carried out, and recommendations for their elimination were proposed (method of passive thermal control).

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Greensfelder, Erik M., Gregor P. Henze, and Clemens Felsmann. "An investigation of optimal control of passive building thermal storage with real time pricing." Journal of Building Performance Simulation 4, no. 2 (June 2011): 91–104. http://dx.doi.org/10.1080/19401493.2010.494735.

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Walimbe, Pratik, and Shubham Padekar. "Evolutionary Insights into the State-of-the-Art Passive Thermal Control Systems for Thermodynamic Stability of Smallsats." Advanced Engineering Forum 35 (February 2020): 29–45. http://dx.doi.org/10.4028/www.scientific.net/aef.35.29.

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‘Smallsats,’ originated in the 1990s and popularized again since 2005, is a newly emerging miniaturized form of conventional satellites. Characterized by low mass (usually under 500 kg) and compact dimensions, Smallsats are one of the most sought-after forms of satellites, thanks to the ease offered by the lightweight. However, this privilege brings with itself the significant impediments such as excessive heat generation arising from the compact stature during peak hours of operation, external heat load as a result of radiation. These heat loads manifest themselves as the direct solar flux, earth’s albedo, and earth’s infrared radiation. Sudden temperature drop within the eclipse region results in the permanent-equipmental damage of the electronic circuitry involved, the direct consequence of which is the out-of-tolerance performance of the satellite. Thermal Control Systems (TCS) is the most plausible solution in this regard whose chief objective in any spacecraft or a satellite is to maintain all the subsystems along with the payload components within the stipulated temperature limits for each mission phase. This paper presents the passive thermal control systems (PTCS) in cube-sats. Starting with the discussion of the thermal environment, typical concepts like albedo, earth IR are shed light on. Subsequent discussions follow the study of thermal surface finishes and multi-layer insulations (MLI). Finally, the applications of phase-change materials (PCM) in thermal control systems of cube-sats are introduced. The constant trade-offs between the optimal thermal finish and the overall performance, arising due to incurrence of contamination during synthesis, SLI-MLI thickness and cost associated with increasing thickness and the phase-change materials (PCM’s) and their compatibility, have always been at the pin-point of the research. The widespread importance of thermal control systems is attributed to its ability to ensure the meetings of the gradient requirements, a parameter playing a crucial role in spacecraft dynamics.

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Karpov, D. "APPLICATION OF ACTIVE AND PASSIVE THERMAL CONTROL IN DEFECTOSCOPY OF CONSTRUCTION MATERIALS AND PRODUCTS, FILLER STRUCTURES OF BUILDINGS AND CONSTRUCTIONS." Construction Materials and Products 2, no. 4 (June 27, 2020): 39–44. http://dx.doi.org/10.34031/2618-7183-2019-2-4-39-44.

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one of the perspective and modern methods of nondestructive testing – thermal control is considered. The possibilities and advantages of thermal control in the identification of defects in various building materials and products, enclosing structures of buildings and structures are given. The short characteristics of the main defects of building materials and products, buildings and structures are proposed. The basic principles of identification of hidden (invisible) and obvious (visible) defects are briefly considered and practical results of construction flaw detection of objects for various purposes with the use of thermal imaging equipment are presented. On the example of a fragment of the enclosing building structure of piece building products in the form of ceramic bricks with artificially created technical defects in the process of qualitative analysis of thermograms zone of thermal temperature anomalies (method of active thermal control) are localized. For some enclosing structures of buildings and structures based on the results of thermal imaging identified obvious thermal defects, their qualitative analysis and recommendations for elimination (method of passive thermal control) are made.

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Algieri, Angelo, Mario Amelio, and Pietropaolo Morrone. "A Comparative Energetic Analysis of Active and Passive Emission Control Systems Adopting Standard Emission Test Cycles." Modelling and Simulation in Engineering 2012 (2012): 1–8. http://dx.doi.org/10.1155/2012/786252.

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The present work aims at analysing and comparing the thermal performances of active and passive aftertreatment systems. A one-dimensional transient model has been developed in order to evaluate the heat exchange between the solid and the exhaust gas and to estimate the energy effectiveness of the apparatus. Furthermore, the effect of the engine operating conditions on the performances of emission control systems has been investigated considering standard emission test cycles. The analysis has demonstrated that the active flow control presents the higher thermal inertia and it appears more suitable to maintain the converter initial temperature level for a longer time after variations in engine load. Conversely, the traditional passive flow control is preferable when rapid “cooling” or “heating” of the solid phase is requested. Moreover, the investigation has highlighted the significant influence of the cycle time and converter length on the energetic performances of the aftertreatment apparatus.

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Hayashi, Motoya, Hoon kim, Yoshinori Honma, and Junichiro Matsunaga. "Feasibility of a Passive Ventilation System with a Thermal Damper - Simulations and measurement results of an experimental house in a mild region of Japan -." E3S Web of Conferences 111 (2019): 06047. http://dx.doi.org/10.1051/e3sconf/201911106047.

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In order to retain good indoor air quality through the year in detached houses with passive ventilation systems, the authors investigated a mechanical control air-supply method. Firstly, indoor environments in houses with passive ventilation systems with thermal dampers, were examined using a simulation program (Fresh). Secondly, a passive ventilation system with a thermal damper, an under-floorheating system with a heat pump and were installed in an airtight house at Maebashi in Japan and measurements on its ventilation characteristics and indoor air quality were made. The simulation results showed that if the thermal damper is well tuned, this mechanically controlled air-supply opening keeps ventilation rates adequate through the year especially in airtight houses. The measurement results showed that the ventilation rates were kept above the required level through the year and the TVOC concentration decreases from 3000 to 200 μg/m3 in 5 months after the construction.

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Gamage, Sampath, Debashree Banerjee, Md Mehebub Alam, Tomas Hallberg, Christina Åkerlind, Ayesha Sultana, Ravi Shanker, et al. "Reflective and transparent cellulose-based passive radiative coolers." Cellulose 28, no. 14 (August 7, 2021): 9383–93. http://dx.doi.org/10.1007/s10570-021-04112-1.

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AbstractRadiative cooling passively removes heat from objects via emission of thermal radiation to cold space. Suitable radiative cooling materials absorb infrared light while they avoid solar heating by either reflecting or transmitting solar radiation, depending on the application. Here, we demonstrate a reflective radiative cooler and a transparent radiative cooler solely based on cellulose derivatives manufactured via electrospinning and casting, respectively. By modifying the microstructure of cellulose materials, we control the solar light interaction from highly reflective (> 90%, porous structure) to highly transparent (≈ 90%, homogenous structure). Both cellulose materials show high thermal emissivity and minimal solar absorption, making them suitable for daytime radiative cooling. Used as coatings on silicon samples exposed to sun light at daytime, the reflective and transparent cellulose coolers could passively reduce sample temperatures by up to 15 °C and 5 °C, respectively.

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Fořt, Jan, Magdaléna Doleželová, Václav Kočí, and Robert Černý. "Functional Properties of SAP-Based Humidity Control Plasters." Polymers 13, no. 14 (July 12, 2021): 2279. http://dx.doi.org/10.3390/polym13142279.

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The application of materials with high moisture storage capacity close to the interior surface presents a prospective passive method for improving indoor relative humidity conditions. In this paper, lime-cement plasters containing three different types of superabsorbent polymers (SAPs) in varying dosages are introduced and their mechanical, hygric, and thermal characteristics are analyzed in a relation to microstructure. The experimental results show a significant effect of both SAP amount and chemical composition on all functional properties of studied plasters. The incorporation of 1.5% of SAP may induce up to 2.5 better moisture buffering, thus significantly improving the passive humidity control capability. Considering overall functional parameters of SAP-modified plasters, the dosage of 1 wt.% can thus be viewed as a rational compromise between the moisture storage capability and mechanical properties. The obtained wide sets of parameters can be utilized directly as input data of computational models suitable for the assessment of the interior microclimate of residential and administrative buildings.

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Journal articles on the topic 'Passive thermal control'

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