Academic literature on the topic 'Cooling approaches'

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Journal articles on the topic "Cooling approaches"

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Mazzei, Lorenzo, Antonio Andreini, and Bruno Facchini. "Assessment of modelling strategies for film cooling." International Journal of Numerical Methods for Heat & Fluid Flow 27, no. 5 (May 2, 2017): 1118–27. http://dx.doi.org/10.1108/hff-03-2016-0086.

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Purpose Effusion cooling represents one the most innovative techniques for the thermal management of aero-engine combustors liners. The huge amount of micro-perforations implies a significant computational cost if cooling holes are included in computational fluid dynamics (CFD) simulations; therefore, many efforts are reported in literature to develop lower-order approaches aiming at limiting the number of mesh elements. This paper aims to report a numerical investigation for validating two approaches for modelling film cooling, distinguished according to the way coolant is injected (i.e. through either point or distributed mass sources). Design/methodology/approach The approaches are validated against experimental data in terms of adiabatic effectiveness and heat transfer coefficient distributions obtained for effusion cooled flat plates. Additional reynolds-averaged naver stokes (RANS) simulations were performed meshing also the perforation, so as to distinguish the contribution of injection modelling with respect to intrinsic limitations of turbulence model modelling. Findings Despite the simplified strategies for coolant injection, this work clearly shows the feasibility of obtaining a sufficiently accurate reproduction of coolant protection in conjunction with a significant saving in terms of computational cost. Practical/implications The proposed methodologies allow to take into account the presence of film cooling in simulations of devices characterized by a huge number of holes. Originality/value This activity represents the first thorough and quantitative comparison between two approaches for film cooling modelling, highlighting the advantages involved in their application.
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El-Bealy, M. "Monotonic and Fluctuated Cooling Approaches in Secondary Cooling Zones During Continuous Casting." Canadian Metallurgical Quarterly 36, no. 1 (January 1997): 49–56. http://dx.doi.org/10.1179/cmq.1997.36.1.49.

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ELBEALY, M. "Monotonic and fluctuated cooling approaches in secondary cooling zones during continuous casting." Canadian Metallurgical Quarterly 36, no. 1 (January 1997): 49–56. http://dx.doi.org/10.1016/s0008-4433(96)00034-1.

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Li, Yang, Zhifu Zhou, Jian Zhao, Liang Hao, Minli Bai, Yulong Li, Xuanyu Liu, Yubai Li, and Yongchen Song. "Three-Dimensional Thermal Simulations of 18650 Lithium-Ion Batteries Cooled by Different Schemes under High Rate Discharging and External Shorting Conditions." Energies 14, no. 21 (October 25, 2021): 6986. http://dx.doi.org/10.3390/en14216986.

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In this work, three-dimensional thermal simulations of single 18650 lithium-ion battery cell and 75 V lithium-ion battery pack composed of 21 18650 battery cells are performed based on a multi-scale multi-domain (MSMD) battery modeling approach. Different cooling approaches’ effects on 18650 lithium-ion battery and battery pack thermal management under fast discharging and external shorting conditions are investigated and compared. It is found that for the natural convection, forced air cooling, and/or mini-channel liquid cooling approaches, the temperature of battery cell easily exceeds 40 °C under 3C rate discharging condition. While under external shorting condition, the temperature of cell rises sharply and reaches the 80 °C in a short period of time, which can trigger thermal runaway and may even lead to catastrophic battery fire. On the other hand, when the cooling method is single-phase direct cooling with FC-72 as coolant or two-phase immersed cooling by HFE-7000, the cell temperature is effectively limited to a tolerable level under both high C rate discharging and external shorting conditions. In addition, two-phase immersed cooling scheme is found to lead to better temperature uniformity according to the 75 V battery pack simulations.
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Parkinson, Thomas, and Marcel Schweiker. "New Approaches to Modelling Occupant Comfort." Buildings 12, no. 7 (July 11, 2022): 985. http://dx.doi.org/10.3390/buildings12070985.

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Madani, Seyed Saeed, Erik Schaltz, and Søren Knudsen Kær. "Design and Simulation of Internal Flowing Twisted Conduits for Cooling of Lithium-Ion Batteries through Thermal Characterization." Batteries 6, no. 2 (May 26, 2020): 31. http://dx.doi.org/10.3390/batteries6020031.

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Lithium-ion batteries are extensively used for electric vehicles, owing to their great power and energy density. A battery thermal management system is essential for lithium-ion batteries. With the extensive utilization of liquid-cooling approaches for lithium-ion batteries’ thermal management, temperature homogeneity is considerably influenced by coolant distribution. A lower temperature of the cooling fluid brings about a lower temperature of the cell, but the relation and the amount are important to be analyzed. The cooling efficiency is considerably influenced by the flowing conduit arrangement in the cooling plate. Different parameters are affected by the cooling performance of the battery pack. Consequently, the effect of entrance temperature of coolant fluid, current rate, environment temperature, entrance velocity of the coolant fluid, and plate material on the performance and efficiency of a battery thermal management system were investigated. In this investigation, the program ANSYS/FLUENT was employed as the numerical solver to solve the problem. The simulation was accomplished after the end of the discharge. It was seen that the temperature distributions were the most sensitive to the entrance velocity of coolant fluid. It was concluded that the entrance velocity of coolant fluid has the greatest impact on the cooling efficiency and performance of the cold plate.
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Paredes, S., Y. Madhour, G. Schlottig, C. L. Ong, and T. Brunschwiler. "(Invited) Wafer-Level Integration of Embedded Cooling Approaches." ECS Transactions 64, no. 5 (August 14, 2014): 253–65. http://dx.doi.org/10.1149/06405.0253ecst.

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Abedrabboh, Omer, Muammer Koç, and Yusuf Biçer. "Sustainability performance of space-cooling technologies and approaches." Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 44, no. 4 (October 4, 2022): 9017–42. http://dx.doi.org/10.1080/15567036.2022.2127979.

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Nebot, Àngela, and Francisco Mugica. "Energy Performance Forecasting of Residential Buildings Using Fuzzy Approaches." Applied Sciences 10, no. 2 (January 20, 2020): 720. http://dx.doi.org/10.3390/app10020720.

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The energy consumption used for domestic purposes in Europe is, to a considerable extent, due to heating and cooling. This energy is produced mostly by burning fossil fuels, which has a high negative environmental impact. The characteristics of a building are an important factor to determine the necessities of heating and cooling loads. Therefore, the study of the relevant characteristics of the buildings, regarding the heating and cooling needed to maintain comfortable indoor air conditions, could be very useful in order to design and construct energy-efficient buildings. In previous studies, different machine-learning approaches have been used to predict heating and cooling loads from the set of variables: relative compactness, surface area, wall area, roof area, overall height, orientation, glazing area and glazing area distribution. However, none of these methods are based on fuzzy logic. In this research, we study two fuzzy logic approaches, i.e., fuzzy inductive reasoning (FIR) and adaptive neuro fuzzy inference system (ANFIS), to deal with the same problem. Fuzzy approaches obtain very good results, outperforming all the methods described in previous studies except one. In this work, we also study the feature selection process of FIR methodology as a pre-processing tool to select the more relevant variables before the use of any predictive modelling methodology. It is proven that FIR feature selection provides interesting insights into the main building variables causally related to heating and cooling loads. This allows better decision making and design strategies, since accurate cooling and heating load estimations and correct identification of parameters that affect building energy demands are of high importance to optimize building designs and equipment specifications.
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Dzhedzhula, V. "MODERN APPROACHES TO FORMATION HYDRAULIC MODES OF COOLING SUPPLY SYSTEMS." Modern technology, materials and design in construction 30, no. 1 (2021): 126–31. http://dx.doi.org/10.31649/2311-1429-2021-1-126-131.

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In modern conditions, the practice of building multi-storey office buildings, shopping centers and catering establishments where the installation of air conditioning systems is necessary is becoming widespread. In addition to regulatory requirements, the need for air conditioning systems is dictated by market conditions: a building in which optimal microclimatic conditions are created has significant competitive advantages in terms of renting, selling and operating compared to a building without ventilation and air conditioning systems. The main approaches to the installation of air conditioning systems are as follows: central air conditioning combined with ventilation and air heating; the use of local closers where the coolant is water - climate beams, fan coils; use of freon local systems - local and multizonal. Given the frequent inconsistency of planning and operational decisions of these buildings, due to the fact that different tenants may have different needs for the installation of air conditioning systems, different heat surpluses and other hazards, the installation of water cooling systems is one of the best solutions. within the limits of modernization of the system in accordance with the new operational features. Water cooling systems require the creation of an optimal hydraulic regime, which will not only allow optimal operation of refrigeration equipment, but also save energy. A significant difference in the formation of the hydraulic environment with constant and variable mode has formed the objectives of the study and confirms their relevance. The article considers the approaches to the formation of hydraulic modes of the refrigeration system. The results of the research were implemented during the construction of a real public facility. On the example of this object, the economic indicators of the formation of different hydraulic modes of the refrigeration system are determined. The use of the correct schemes for the formation of hydraulic modes of water cooling systems will significantly increase the energy efficiency of the process of forming the internal microclimate of these premises.
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Dissertations / Theses on the topic "Cooling approaches"

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Gupta, Vishal. "Experimental investigations into rotary ultrasonic drilling of bones - an in vitro study." Thesis, IIT Delhi, 2017. http://localhost:8080/iit/handle/2074/7249.

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Bouzoukas, Asterios. "New approaches for cooling photovoltaic/thermal (PV/T) systems." Thesis, University of Nottingham, 2008. http://eprints.nottingham.ac.uk/11148/.

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Today the majority of UK's energy needs are met by fossil fuels. An energy sector that uses 30% of this energy and generates 28% of the total emissions is domestic sector. To reduce the emissions generated by fossil fuels UK government decided to increase the energy coming from renewable sources by 2020. A renewable energy that can contribute is solar energy. Solar thermal collectors and photovoltaics are two means of transforming solar energy to thermal and electrical energy. The limited space in the roofs and the cost of the technologies will prevent families to use both systems together in their roof A hybrid energy system combine the use of two or more alternative power sources will help to increase the system's total efficiency. The photovoltaic/thermal (PV/T) system is a hybrid structure that converts part of the sun's radiation to electricity and part to thermal energy. This research work focuses on the production of new approaches on hybrid PV/T systems. PV/T systems using water and air have been introduced and a literature review conducted in order to identify positives and negatives of these systems. Experiments also conducted by using water and air as heat transfer medium, and the results helped to work as a benchmark performance to the new approaches. These technologies were heat pipes, phase change materials and micro encapsulated phase change materials. The technologies exist for years but their use in the specific application is new. A literature review was undertaken to provide an understanding of these technologies and identified findings that have contributed to the design of the systems. Experimental work was carried out incorporating these technologies in the rear of a PV and the results indicated comparable performance with PV/T-water and PV/Tair. Five performance indicators were employed to help with the comparison of the systems. These were electrical and thermal efficiency, the total energy efficiency, the primary energy saving efficiency and the exergy efficiency. From these five indicators the primary energy saving efficiency that shows how much fossil fuel is saved and the exergy efficiency that could give the optimum working conditions of each system was the most valuable ratings. For the PV/PCM model a new simulation program was developed to help validate the experimental work. Also an environmental and economic study was undertaken to compare if the new systems could help reduce the C02 emissions and if they were feasible to become commercial products. Finally the conclusions gained have been presented and recommendations fo r future work have been made.
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McBee, Brian K. "Computational Approaches to Improving Room Heating and Cooling for Energy Efficiency in Buildings." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/28911.

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With a nation-wide aim toward reducing operational energy costs in buildings, it is important to understand the dynamics of controlled heating, cooling, and air circulation of an individual room, the "One-Room Model Problem." By understanding how one most efficiently regulates a room's climate, one can use this knowledge to help develop overall best-practice power reduction strategies. A key toward effectively analyzing the "One-Room Model Problem" is to understand the capabilities and limitations of existing commercial tools designed for similar problems. In this thesis we develop methodology to link commercial Computational Fluid Dynamics (CFD) software COMSOL with standard computational mathematics software MATLAB, and design controllers that apply inlet airflow and heating or cooling to a room and investigate their effects. First, an appropriate continuum model, the Boussinesq System, is described within the framework of this problem. Next, abstract and weak formulations of the problem are described and tied to a Finite Element Method (FEM) approximation as implemented in the interface between COMSOL and MATLAB. A methodology is developed to design Linear Quadratic Regulator (LQR) controllers and associated functional gains in MATLAB which can be implemented in COMSOL. These "closed-loop" methods are then tested numerically in COMSOL and compared against "open-loop" and average state closed-loop controllers.
Ph. D.
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Tauch, Jonas [Verfasser], and Matthias [Akademischer Betreuer] Weidemüller. "New approaches for cooling molecular anions to the Kelvin range / Jonas Tauch ; Betreuer: Matthias Weidemüller." Heidelberg : Universitätsbibliothek Heidelberg, 2021. http://d-nb.info/1236345460/34.

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Herrera, Santisbon Eunice. "Production-consumption system coordination by hybrid predictive approaches : application to a solar cooling system for buildings." Thesis, CentraleSupélec, 2015. http://www.theses.fr/2015SUPL0006/document.

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Garantir le confort thermique des bâtiments est directement lié à la consommation d'énergie. Dans les zones tropicales, les systèmes de refroidissement représentent l'un des postes les plus gourmands en énergie. Afin de réduire la consommation d'énergie mondiale, il est primordial d'améliorer l'efficacité de ces systèmes ou bien de développer de nouvelles méthodes de production de froid. Une installation de refroidissement solaire basé sur le cycle à absorption est une alternative pour réduire les émissions de gaz à effet de serre et la consommation d'électricité. Contrairement aux systèmes classiques de refroidissement à compression mécanique, la production de froid par absorption est un système complexe composé de plusieurs composants comme des panneaux solaires, un ballon de stockage, une tour de refroidissement et une machine à absorption. Outre le dimensionnement des composants, ce système complexe nécessite des actions de contrôle pour être efficace parce que la coordination entre le stockage d'eau chaude, la production et la consommation du froid est nécessaire. Le but de cette thèse est de proposer une structure producteur-consommateur d'énergie basée sur la commande prédictive (MPC). Le système de refroidissement par absorption solaire est considéré comme faisant partie de ce système de production-consommation d'énergie, le système de stockage d'eau chaude est le producteur et la machine à absorption qui distribue de l'eau froide au bâtiment est l'un des consommateurs. Pour que la structure de commande soit modulaire, la coordination entre les sous-systèmes est réalisée en utilisant une approche de partitionnement où des contrôleurs prédictifs locaux sont conçus pour chacun des sous-systèmes. Les contrôleurs des consommateurs calculent un ensemble de profils de demande d'énergie. Ces profils sont ensuite envoyés au contrôleur du producteur qui sélectionne le profil qui minimise le coût global. Dans une première partie, l'approche proposée est testée sur un modèle linéaire simplifié composé d'un producteur et plusieurs consommateurs. Dans une deuxième partie, un cas plus complexe est étudié. Un modèle simplifié d'un système de refroidissement à absorption est évaluée en utilisant l'outil de simulation TRNSYS. Le modèle de production n'est plus linéaire, il est décrit par un modèle non linéaire hybride qui augmente la complexité du problème d'optimisation. Les résultats des simulations montrent que la sous-optimalité induite par la méthode est faible. De plus, la performance de l'approche atteint les objectifs de commande tout en respectant les contraintes
To guarantee thermal comfort in buildings is directly related to energy consumption. In tropical climates, cooling systems for buildings represent one of the largest energy consumers. Therefore, as energy consumption is a major concern around the world, it is important to improve the systems efficiency or seeking new methods of cooling production. A solar cooling installation based on the absorption cycle is an alternative to mitigate greenhouse gas emissions and electricity consumption. In contrast to conventional vapor-compression based cooling systems, the absorption cooling production involves a complex system composed of several components as collector panel, storage tank, cooling tower and absorption chiller. Besides the sizing of the components, this complex system requires control actions to be efficient as a coordination between hot water storage, cooling water production and consumption is necessary. The aim of this research is to propose a management approach for a production-consumption energy system based on Model Predictive Control (MPC). The solar absorption cooling system is seen as part of this production-consumption energy system where the hot water storage system is the producer and the chiller-building system is one of the consumers. In order to provide modularity to the control structure, the coordination between the subsystems is achieved by using a partitioning approach where local predictive controllers are developed for each of the subsystems. The consumer controllers compute a set of energy demand profiles sent to the producer controller which selects the profile that better minimize the global optimization cost. In a first part, the proposed approach is tested on a simplified linear model composed of one producer and several consumers. In a second part, a more complex case is studied. A simplified model of an absorption cooling system is evaluated using the simulation tool TRNSYS. The producer model is no longer linear, instead it is described by a nonlinear hybrid model which increases the complexity of the optimization problem. The simulations results show that the suboptimality induced by the method is low and the control strategy fulfills the objectives and constraints while giving good performances
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Landi, Daniele. "Knowledge-based approaches to support the design and development of the electrochemical storage systems." Doctoral thesis, Università Politecnica delle Marche, 2014. http://hdl.handle.net/11566/242838.

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L’esigenza di abbreviare il cosiddetto “time-to-market” è prerogativa di tutte le imprese che operano nei vari settori industriali, al fine di ritagliarsi una vantaggiosa posizione nel mercato, nei confronti dei concorrenti. Il processo di progettazione si è concentrato principalmente sulla riduzione dei costi, diminuendo i tempi di produzione, senza diminuire la qualità del prodotto. Al giorno d'oggi anche gli aspetti ambientali ricoprono un ruolo fondamentale e rappresentano un fattore importante per il successo sul mercato dei prodotti, infatti, tra i consumatori si sta sviluppando una sensibilità ambientale sempre crescente. Da queste considerazioni viene alla luce l’esigenza di studiare e sviluppare un approccio basato sulla conoscenza in grado di assistere i progettisti durante tutta la vita del prodotto, analizzando gli aspetti legati alle prestazioni, ai costi ed agli aspetti ambientali. Di conseguenza una delle problematiche più importanti è quella di riuscire a diminuire i costi e i tempi di passaggio tra idea e lancio sul mercato; avere perciò a disposizione delle tecnologie, in grado di prevedere i comportamenti reali dei vari sistemi, determina un notevole vantaggio in termini economici ed organizzativi. Le aziende di successo sono quelle in grado di migliorare le risorse umane e che hanno creato condizioni particolari in grado di far evolvere e sviluppare le conoscenze e know-how. Queste considerazioni sono sempre più necessarie quando si considera l'evoluzione dell'economia occidentale, in cui, ci troviamo di fronte a dover produrre prodotti personalizzati di elevata quantità. La sfida per le imprese di ingegneria italiana è quello di vendere prodotti di qualità continuando a sviluppare soluzioni innovative in modo rapido, e mantenendo bassi i costi. Per poter rispondere a questa sfida le aziende devono investire sempre di più nel processo di progettazione al fine di garantire il futuro della stessa società con strategie dedicate per l'innovazione e la tecnologia.Gli obiettivi di questo lavoro possono essere sintetizzati come la definizione di un nuovo approccio di progettazione, basato sulla conoscenza in grado di fornire nuovi strumenti per l’analisi e le valutazioni delle prestazioni dei prodotti in differenti scenari applicativi. Il lavoro svolto si sofferma sull’analisi dei sistemi di accumulo di ultima generazione costituiti da batterie agli ioni litio utilizzate sia nell’ambito dell’autotrazione che in applicazioni stazionarie. È comunque possibile applicare la metodologia di lavoro descritta anche ad altri casi applicativi. Per quanto riguarda la progettazione di pacchi batteria, il lavoro svolto rappresenta un primo passo per la definizione e progettazione dei sistemi di accumulo agli ioni di litio. In particolare, all’interno di questa tesi di ricerca è stato analizzato lo stato dell’arte dei principali sistemi di accumulo, soffermando l’attenzione sulla tecnologia al litio e dei loro principali problemi di utilizzo. Una profonda analisi è stata effettuata per la determinazione del calore generato dalle singole batterie al litio durante il loro funzionamento. I risultati della ricerca sono stati applicati a piccole produzioni personalizzate, sia di veicoli elettrici, sia di sistemi di accumulo per abitazioni.
The need to shorten the "time-to-market" is the prerogative of all companies that operate in different industry sectors, in order to carve out a profitable position in the market against competitors. The design process has focused primarily on reducing costs, reducing production times, without decreasing the quality of the product. Nowadays also the environmental aspects play a key role and is an important factor for the success of the products on the market , in fact, a growing environmental awareness is developing among consumers . From these considerations it comes to light the need to study and develop a knowledge-based approach able to assist designers during the lifetime of the product , analyzing the aspects related to performance, cost and environmental aspects. Therefore one of the most important problems is to be able to decrease the cost and time of passage between idea and market launch; therefore have available technologies, able to predict the actual behavior of the various systems, determines a considerable advantage in terms of economic and organizational links. Successful companies are those that can improve human resources and having created special conditions able to evolve and develop the knowledge and know-how. These considerations are becoming more necessary when we consider the evolution of the western economy, in which we find ourselves faced with having to produce high quantities of customized products. The challenge for Italian engineering companies is to sell quality products while continuing to develop innovative solutions quickly, and keeping costs low . To meet this challenge, companies need to invest more and more in the design process to ensure the future of the company with dedicated strategies for innovation and technology. The objectives of this work can be summarized as the definition of a new design approach , based on knowledge which can provide new tools for the analysis and assessment of the performance of products in different application scenarios. The work focuses on the analysis of next generation storage systems consisting of lithium-ion batteries used both in automotive and stationary applications . You can still apply the methodology described also working with other application cases . With regard tothe design of battery packs , the work represents a first step in the definition and design of the lithium-ion storage systems battery . In particular , within this thesis the state of the main storage systems has been analyzed , our attention is on lithium-ion technology and their main usage problems . A deep analysis was performed for the determination of the heat generated by the individual lithium batteries during their operation . The research results have been applied to small-scale production customization, both of electric vehicles, and energy storage systems for homes.
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Sosa, Pieroni Jhosmar L. "Estimation of water footprints and review of water-saving/recovery approaches in coal-fired power plants' cooling systems." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1367938141.

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Hasan, M. Mahmudul. "Investigation of energy efficient approaches for the energy performance improvement of commercial buildings." Thesis, Queensland University of Technology, 2013. https://eprints.qut.edu.au/61050/1/M._Hasan_Thesis.pdf.

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Energy efficiency of buildings is attracting significant attention from the research community as the world is moving towards sustainable buildings design. Energy efficient approaches are measures or ways to improve the energy performance and energy efficiency of buildings. This study surveyed various energy-efficient approaches for commercial building and identifies Envelope Thermal Transfer Value (ETTV) and Green applications (Living wall, Green facade and Green roof) as most important and effective methods. An in-depth investigation was carried out on these energy-efficient approaches. It has been found that no ETTV model has been developed for sub-tropical climate of Australia. Moreover, existing ETTV equations developed for other countries do not take roof heat gain into consideration. Furthermore, the relationship of ETTV and different Green applications have not been investigated extensively in any literature, and the energy performance of commercial buildings in the presence of Living wall, Green facade and Green roof has not been investigated in the sub-tropical climate of Australia. The study has been conducted in two phases. First, the study develops the new formulation, coefficient and bench mark value of ETTV in the presence of external shading devices. In the new formulation, roof heat gain has been included in the integrated heat gain model made of ETTV. In the 2nd stage, the study presents the relationship of thermal and energy performance of (a) Living wall and ETTV (b) Green facade and ETTV (c) Combination of Living wall, Green facade and ETTV (d) Combination of Living wall, Green Roof and ETTV in new formulations. Finally, the study demonstrates the amount of energy that can be saved annually from different combinations of Green applications, i.e., Living wall, Green facade; combination of Living wall and Green facade; combination of Living wall and Green roof. The estimations are supported by experimental values obtained from extensive experiments of Living walls and Green roofs.
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Blake, Tony. "A quantum approach to cavity mediated laser cooling." Thesis, University of Leeds, 2011. http://etheses.whiterose.ac.uk/2167/.

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Cavity-mediated cooling has the potential to become one of the most efficient techniques to cool molecular species down to very low temperatures. This thesis studies the use of rate equations to analyse the cooling process in such systems. In particular the master equation is used to find rate equations that can determine the rate of change of phonons in the system. The general idea behind cavity cooling is the continuous conversion of phonons into cavity photons. While there is no spontaneous emission and decay rate associated with the concept of phonons, photons are created after a change in the phonon number has occurred and can then leak out through the cavity mirrors easily. Hence the conversion of phonons into photons can result in the constant removal of phonon energy from the system. In this thesis we compare cavity mediated cooling with single particle laser cooling. It is shown that cavity cooling is essentially the same as ordinary laser cooling. This is done by calculating the stationary state phonon number mss and the cooling rate y as a function of the system parameters. For example, when the trap phonon frequency υ is either much larger or much smaller than the cavity decay rate k , the minimum stationary state phonon number scales as k²/16v² (strong confinement regime) and as k/4 (weak confinement regime), respectively. Replacing k with Ѓ yields the steady states associated with ordinary laser cooling.
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McGinley, Susan. "Cooling Cows: A Metabolic Approach to Managing Heat Stress." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2007. http://hdl.handle.net/10150/622131.

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Books on the topic "Cooling approaches"

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Park, Sharon C. Heating, ventilating, and cooling historic buildings: Problems and recommended approaches. [Washington, DC]: U.S. Dept. of the Interior, National Park Service, Cultural Resources, Preservation Assistance, 1991.

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Bejan, Adrian, and Giuseppe Grazzini, eds. Shape and Thermodynamics. Florence: Firenze University Press, 2008. http://dx.doi.org/10.36253/978-88-8453-836-9.

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Shape and Thermodynamics is a two-day international Workshop focused on the Constructal Theory of generation of configuration in nature and engineering. From the early developments related to tree configurations for the cooling of electronics, today Constructal theory is being applied to conceptual design of transportation net-works, river basins, living bodies, building materials and many other flow systems. Constructal theory is also enriching thermo-dynamics, from basic theory to design and optimization. This theory approaches design "as science", with the generation of configuration regarded as a phenomenon of all physics, based on principle (the Constructal law). For example, Constructal Theory contributes to the evolution of fuel cells, in the design of cooling channels, the optimal feeding of reactants, etc. Important applications are also found in the design of heat exchangers, district heating networks, etc. The growing scientific literature on Constructal Theory has an important Italian component, although further dissemination is timely. Moreover, the relation with other thermodynamic research areas deserves to be explored. Website: Shape and Thermodinamics
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Kanefsky, Peter. A systems approach to engine cooling design. Warrendale, PA: Society of Automotive Engineers, 1999.

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Combined heating, cooling & power handbook: Technologies & applications an integrated approach to energy resource optimization. 2nd ed. Lilburn, GA: The Fairmont Press, 2012.

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C, Landa Henry, and Landa Henry C, eds. The Solar energy handbook: A practical engineering approach to the application of solar energy to the needs of man and the environment : including sections on terrestrial cooling, wind power, calculations and computer programs. 6th ed. Wauwatosa, WI: Film Instruction Co. of America, 2005.

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A Systems Engineering Approach to Engine Cooling Design. Society of Automotive Engineers Inc, 1999.

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Petchers, Neil. Combined Heating, Cooling & Power Handbook: Technologies & Applications : An Integrated Approach to Energy Conservation. Fairmont Press, 2002.

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Combined Heating, Cooling & Power Handbook: Technologies & Applications: An Integrated Approach to Energy Resource Optimization. Fairmont Press, 2002.

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Burch, David W. A systems approach to financial appraisal of greenhouse heating with power plant cooling water. 1985.

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Combined Heating, Cooling & Power Handbook: Technologies & Applications : An Integrated Approach to Energy Conservation/Resource Optimization. Fairmont Press, 2002.

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Book chapters on the topic "Cooling approaches"

1

Chandrasekar, Murugesan, Tamilkolundu Senthilkumar, and Poornanandan Gopal. "Cooling Approaches for Solar PV Panels." In The Effects of Dust and Heat on Photovoltaic Modules: Impacts and Solutions, 213–34. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-84635-0_8.

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Singh, S. K., and R. Paul Singh. "Air Impingement Cooling of Cylindrical Objects Using Slot Jets." In Food Engineering: Integrated Approaches, 89–104. New York, NY: Springer New York, 2008. http://dx.doi.org/10.1007/978-0-387-75430-7_5.

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Karmanenko, Sergey, Alexander Semenov, Antonina Dedyk, Andrey Es’kov, Alexey Ivanov, Pavel Beliavskiy, Yulia Pavlova, et al. "New Approaches to Electrocaloric-Based Multilayer Cooling." In Electrocaloric Materials, 183–223. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-40264-7_8.

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Imani, Negin, and Brenda Vale. "Biomimicry and Its Approaches to Energy-Efficient Building Design." In Heating with Wolves, Cooling with Cacti, 21–42. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003081937-3.

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Zhang, Xingxing, Xinru Wang, and Xudong Zhao. "Solar System Design and Energy Performance Assessment Approaches." In Advanced Energy Efficiency Technologies for Solar Heating, Cooling and Power Generation, 417–51. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-17283-1_12.

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Talukdar, Kamaljyoti. "Use of Gas Turbine Operated by Municipal Solid Waste to Obtain Power and Cooling Assisted by Vapour Absorption Refrigeration System." In Integrated Approaches Towards Solid Waste Management, 79–85. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-70463-6_8.

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Broadbent, Clive. "Australian Risk Management Approaches to Control of Legionella in Cooling Water Systems." In Legionella, 371–75. Washington, DC, USA: ASM Press, 2014. http://dx.doi.org/10.1128/9781555817985.ch76.

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König, Valentina, Michael Rom, and Siegfried Müller. "A Coupled Two-Domain Approach for Transpiration Cooling." In Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 33–49. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53847-7_2.

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Abstract Transpiration cooling is an innovative cooling concept where a coolant is injected through a porous ceramic matrix composite (CMC) material into a hot gas flow. This setting is modeled by a two-domain approach coupling two models for the hot gas domain and the porous medium to each other by coupling conditions imposed at the interface. For this purpose, appropriate coupling conditions, in particular accounting for local mass injection, are developed. To verify the feasibility of the two-domain approach numerical simulations in 3D are performed for two different application scenarios: a subsonic thrust chamber and a supersonic nozzle.
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Schiller, Gary F. "Cooling." In A Practical Approach to Scientific Molding, 99–109. München: Carl Hanser Verlag GmbH & Co. KG, 2018. http://dx.doi.org/10.3139/9781569906873.010.

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Mosher, Michael, and Kenneth Trantham. "Cooling and Fermenting." In Brewing Science: A Multidisciplinary Approach, 263–312. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-46394-0_9.

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Conference papers on the topic "Cooling approaches"

1

Neuffer, David. "New approaches to final cooling." In ADVANCED ACCELERATOR CONCEPTS 2016: 16th Advanced Accelerator Concepts Workshop. Author(s), 2016. http://dx.doi.org/10.1063/1.4965686.

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Schultz, Mark D., Pritish R. Parida, and Timothy Chainer. "Microprocessor Performance with Multiple Cooling Approaches." In 2022 21st IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (iTherm). IEEE, 2022. http://dx.doi.org/10.1109/itherm54085.2022.9899530.

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Hannemann, Robert, and Herman Chu. "Analysis of Alternative Data Center Cooling Approaches." In ASME 2007 InterPACK Conference collocated with the ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ipack2007-33176.

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The average equipment rack in most of today’s high-performance data centers is limited to 1–3 kW with a typical overall heat load density of less than 100 W/ft2. Near-future racks, however, will dissipate up to 15 kW; in 2–4 years, computer and communications rack heat loads are projected to balloon to 30 kW with heat load densities exceeding 500W/ft2. Handling these heat loads is becoming increasingly difficult and expensive using traditional rack and data center cooling approaches. Based on an analysis of a realistic data center expansion plan, the current paper compares capital and operating costs associated with three alternative cooling approaches: (1) a business-as-usual approach, (2) employment of cooling augmentation systems based on chilled water and refrigerant-based heat exchangers, and (3) deployment of water- and refrigerant-based device-level cooling for some of the heat load. A major conclusion of the work is that challenging current industry norms can result in significant energy savings while allowing the benefits associated with increased functional density.
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Sheik-Bahae, Mansoor. "Multidisciplinary approaches to radiation-balanced lasers (MARBLE): a MURI program by AFOSR (Conference Presentation)." In Optical and Electronic Cooling of Solids II, edited by Richard I. Epstein, Denis V. Seletskiy, and Mansoor Sheik-Bahae. SPIE, 2017. http://dx.doi.org/10.1117/12.2256148.

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Khalil, Ibrahim, Aaron Sahm, and Robert Boehm. "Wet or Dry Cooling?" In ASME 2006 International Solar Energy Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/isec2006-99082.

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Two major aspects related to water use in solar power plants are examined. First we compare the water used in various approaches to power generation. These include water requirements for cooling (where applicable) and other needs within the plant. Included is attention to water requirements for makeup in Rankine cycles, as well as for cleaning of concentrating solar systems. In the second thrust, we examine the impacts of using dry cooling for Rankine cycles. It is generally established that this approach requires premiums in both capital and operating costs (the latter is dependent upon the cost of water), as well as a penalty in performance when compared to wet systems. We examine the trends associated with this technology and outline some for the current performance issues with various cooling approaches.
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Leers, Michael, and Konstantin Boucke. "Cooling approaches for high power diode laser bars." In 2008 58th Electronic Components and Technology Conference (ECTC 2008). IEEE, 2008. http://dx.doi.org/10.1109/ectc.2008.4550100.

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Boyle, R. J. "Effects of Thermal Barrier Coatings on Approaches to Turbine Blade Cooling." In ASME Turbo Expo 2006: Power for Land, Sea, and Air. ASMEDC, 2006. http://dx.doi.org/10.1115/gt2006-91202.

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Reliance on Thermal Barrier Coatings (TBC) to reduce the amount of air used for turbine vane cooling is beneficial both from the standpoint of reduced NOx production, and as a means of improving cycle efficiency through improved component efficiency. It is shown that reducing vane cooling from 10% to 5% of mainstream air can lead to NOx reductions of nearly 25% while maintaining the same rotor, inlet temperature. An analysis is given which shows that, when a TBC is relied upon in the vane thermal design process, significantly less coolant is required using internal cooling alone compared to film cooling. This is especially true for small turbines where internal cooling without film cooling permits the surface boundary layer to remain laminar over a significant fraction of the vane surface.
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Mansouri, Nadia, Rafika El Harabi, and Mohamed Naceur Abdelkrim. "FDI for a cooling system by using graphical approaches." In 2013 International Conference on Control, Decision and Information Technologies (CoDIT). IEEE, 2013. http://dx.doi.org/10.1109/codit.2013.6689663.

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Mhetre, Manisha, Siddharth Jabade, Kedar Sant, Mangesh Chaudhari, and Nitin Satpute. "Air Flow Detection in Data Cooling Center: Different Approaches." In 2018 IEEE Punecon. IEEE, 2018. http://dx.doi.org/10.1109/punecon.2018.8745387.

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Leers, Michael, Konstantin Boucke, Christian Scholz, and Thomas Westphalen. "Next generation of cooling approaches for diode laser bars." In Lasers and Applications in Science and Engineering, edited by Mark S. Zediker. SPIE, 2007. http://dx.doi.org/10.1117/12.701896.

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Reports on the topic "Cooling approaches"

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Bruce. L51942 Refinement of Cooling Rate Prediction Methods for In-Service Welds. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), July 2003. http://dx.doi.org/10.55274/r0010435.

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Welds made onto in-service pipeline are particularly susceptible to hydrogen cracking because of the fast weld cooling rates that tend to result from the ability of the flowing contents to remove heat from the pipe wall. The most commonly used procedures for controlling the risk of hydrogen cracking rely on the use of a sufficiently high heat input level. Two methods currently exist for predicting required heat input levels for welds made onto in-service pipelines: thermal analysis computer modeling and the heat-sink capacity measurement method. The objective of this project was to refine these two complementary methods, and to investigate alternative approaches. The project was divided into three distinct tasks: further refinement of the PRCI Thermal Analysis Model for Hot Tap Welding, standardization of heat-sink capacity measurement, and investigation of alternative approaches to cooling rate prediction. The primary link between the PRCI model and the heat-sink capacity measurement method is the ability of the model to predict the heat-sink capacity of an operating pipeline. Detailed descriptions of user interface modifications required to incorporate the ability to enter the individual heating parameters of interest and have the model calculate the heating rate were developed.
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Gibson and Maxey. L51713 Effective Procedure Variables for Weld onto In-Service Pipelines. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), July 1994. http://dx.doi.org/10.55274/r0010360.

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The ability of the flowing contents to remove heat from the pipe wall causes welds made onto in-service pipelines to cool at an accelerated rate and makes these welds particularly susceptible to hydrogen cracking. Several approaches exist for qualifying procedures where the thermal conditions produced by the flowing pipeline contents are simulated, allowing the ability of a procedure to produce sound, crack-free welds to be demonstrated. This report documents the various methods that can be used, under a number of different conditions, for simulating the proper cooling effects that will be experienced when welding on in-service pipelines. Three candidate methods were selected and evaluated based on their simplicity and their ability to produce realistic weld cooling rates. Several field trials were undertaken in conjunction with actual in-service welding operations conducted by PRCI-member companies, and using a flow loop at the GRI Metering Research Facility, to collect weld cooling rate data to establish which procedure qualification conditions are applicable for various actual in-service conditions.Several field trials were undertaken and documented within this report on actual in-service welding operations as well as using a flow loop at the Gas Research Institute (GRI) Metering Research Facility to collect weld cooling rate data to establish which procedure qualification conditions are applicable for various in-service conditions and pipe repairs.
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Paterson, Andrew H., Yehoshua Saranga, and Dan Yakir. Improving Productivity of Cotton (Gossypsum spp.) in Arid Region Agriculture: An Integrated Physiological/Genetic Approach. United States Department of Agriculture, December 1999. http://dx.doi.org/10.32747/1999.7573066.bard.

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Objectives: We seek to establish the basis for improving cotton productivity under arid conditions, by studying the water use efficiency - evaporative cooling interrelationship. Specifically, we will test the hypothesis that cotton productivity under arid conditions can be improved by combining high seasonal WUE with efficient evaporative cooling, evaluate whether high WUE and/or evaporative cooling are based on specific physiological factors such as diurnal flexibility in stomatal conductance, stomatal density, photosynthetic capacity, chlorophyll fluorescence, and plant water status. Genes influencing both WUE and evaporative cooling, as well as other parameters such as economic products (lint yield, quality, harvest index) of cotton will also be mapped, in order to evaluate influences of water relations on these parameters. Approach: Carbon isotope ratio will be used to evaluate WUE, accompanied by additional parameters to elucidate the relationship between WUE, evaporative cooling, and cotton productivity. A detailed RFLP map will be used to determine the number, location, and phenotypic effects of genes underlying genetic variation in WUE between cultivated cottons, as well as test associations of these genes with traits of economic importance such as harvest index, lint yield, and lint quality. Major Conclusions: Productivity and quality of cotton grown under well-watered versus water-limited conditions was shown to be partly accounted for by different quantitative trait loci (QTLs). Among a suite of physiological traits often found to differ between genotypes adapted to arid versus well-watered conditions, genetic mapping implicated only reduced plant osmotic potential in improved cotton productivity under arid conditions. Our findings clearly implicate OP as a major component of cotton adaptation to arid conditions. However, testing of further physiological hypotheses is clearly needed to account for additional QTL alleles conferring higher seed-cotton yield under arid conditions, such as three of the five we found. Near-isogenic lines being made for QTLs discovered herein will offer a powerful new tool useful toward identification of the underlying gene(s) by using fine-scale mapping approaches (Paterson et al 1990). Implications: Adaptation to both arid and favorable conditions can be combined into the same genotype. We have identified diagnostic DNA markers that are being applied to creation of such desirable genotypes. Simultaneous improvement of productivity (and/or quality) for both arid and irrigated conditions will require more extensive field testing and the manipulation of larger numbers of genes, reducing the expected rate of genetic gain These difficulties may be at least partly ameliorated by efficiencies gained through identification and use of diagnostic DNA markers. Genomic tools and approaches may expedite adaptation of crops to arid cultivation, help to test roles of additional physiological factors, and guide the isolation of the underlying genes that protect crop performance under arid conditions.
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Witzig, Andreas, Camilo Tello, Franziska Schranz, Johannes Bruderer, and Matthias Haase. Quantifying energy-saving measures in office buildings by simulation in 2D cross sections. Department of the Built Environment, 2023. http://dx.doi.org/10.54337/aau541623658.

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A methodology is presented to analyse the thermal behaviour of buildings with the goal to quantify energy saving measures. The solid structure of the building is modelled with finite elements to fully account for its ability to store energy and to accurately predict heat loss through thermal bridges. Air flow in the rooms is approximated by a lumped element model with three dynamical nodes per room. The dynamic model also contains the control algorithm for the HVAC system and predicts the net primary energy consumption for heating and cooling of the building for any time period. The new simulation scheme has the advantage to avoid U-values and thermal bridge coefficients and instead use well-known physical material parameters. It has the potential to use 2D and 3D geometries with appropriate automatic processing from BIM models. Simulations are validated by comparison to IDA ICE and temperature measurement. This work aims to discuss novel approaches to disseminating building simulation more widely.
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Wei J., M. Blaskiewicz, and M. Brennan. Longitudinal Stochastic Cooling Power Requirements: A Coasting-Beam Approach. Office of Scientific and Technical Information (OSTI), January 2004. http://dx.doi.org/10.2172/1061724.

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Jung. L52232 Weld Metal Cooling Rate Prediction of Narrow Groove Pipeline Girth Welds FEA Modeling. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), January 2008. http://dx.doi.org/10.55274/r0011321.

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As part of a larger, DoT-sponsored program to develop optimized weld metal chemistries for X80 and X100, a finite-element approach was used to predict weld metal cooling rates and to provide a better understanding of the factors which influence them. The models can then be used to predict how changes in the welding procedure will affect the cooling rates of the weld joints. The changes in the welding procedure can include the joint details, the heat input of the weld as well as the preheating temperature. The predicted cooling rate from the model will be used as input, along with the weld metal chemistries, to predict the weld metal microstructure and mechanical properties of a completed weld. The cooling rate model and microstructure prediction subroutine will aid in the development of optimized welding consumables that will improve the weldability of X80 and X100 pipelines.
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Nawaz, Kashif. Separate sensible and latent cooling system: A preliminary analysis of a novel approach. Office of Scientific and Technical Information (OSTI), October 2017. http://dx.doi.org/10.2172/1399928.

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Efimov, Anatoly, and Murray Wolinsky. Biologically Cooling the Planet: A BRISK Approach that Directly Connects the Ground to Deep Space. Office of Scientific and Technical Information (OSTI), April 2023. http://dx.doi.org/10.2172/1970263.

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Linker, Raphael, Murat Kacira, Avraham Arbel, Gene Giacomelli, and Chieri Kubota. Enhanced Climate Control of Semi-arid and Arid Greenhouses Equipped with Fogging Systems. United States Department of Agriculture, March 2012. http://dx.doi.org/10.32747/2012.7593383.bard.

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The main objectives were (1) to develop, implement and validate control procedures that would make it possible to maintain year-round air temperature and humidity at levels suitable for crop cultivation in greenhouses operating in arid and semi-arid regions and (2) to investigate the influence of the operational flexibility of the fogging system on the performance of the system. With respect to the development of climate controllers, we developed a new control approach according to which ventilation is used to maintain the enthalpy of the greenhouse air and fogging is used to adjust the humidity ratio inside the greenhouse. This approach is suitable mostly for greenhouses equipped with mechanized ventilation, and in which the air exchange rate can be controlled with enough confidence. The development and initial validation of the controllers were performed in a small experimental greenhouses located at the Agricultural Research Organization and very good tracking were obtained for both air temperature and relative humidity (maximum mean deviations over a 10-min period with constant setpoints lower than 2.5oC and 5% relative humidity). The robust design approach used to develop the controllers made it possible to transfer successfully these controllers to a much larger semi-commercial greenhouse located in the much drier Arava region. After only minimal adjustments, which did not require lengthy dedicated experiments, satisfactory tracking of the temperature and humidity was achieved, with standard deviation of the tracking error lower than 1oC and 5% for temperature and relative humidity, respectively. These results should help promote the acceptance of modern techniques for designing greenhouse climate controllers, especially since given the large variety of greenhouse structures (shape, size, crop system), developing high performance site-specific controllers for each greenhouse is not feasible. In parallel to this work, a new cooling control strategy, which considers the contribution of humidification and cooling from the crop, was developed for greenhouses equipped with natural ventilation. Prior to the development of the cooling strategy itself, three evapotranspiration models were compared in terms of accuracy and reliability. The cooling strategy that has been developed controls the amount of fog introduced into the greenhouse as well as the percentage of vent openings based on the desired vapor pressure deficit (VPD) and enthalpy, respectively. Numerical simulations were used to compare the performance of the new strategy with a constant fogging rate strategy based on VPD, and on average, the new strategy saved 36% water and consumed 30% less electric energy. In addition, smaller air temperature and relative humidity fluctuations were achieved when using the new strategy. Finally, it was demonstrated that dynamically varying the fog rate and properly selecting the number of nozzles, yields additional water and electricity savings.
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Unknown, Author. L51602 Criteria for Hot Tap Welding Further Studies. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), May 1989. http://dx.doi.org/10.55274/r0010102.

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In the gas transmission industry there is a frequent need for modification of existing pipework. Modifications are made primarily by welding on additional pipes and branch connections to existing pipelines. The associated costs of shutting down a pipeline creates a situation whereby it becomes economically feasible to weld onto pipelines containing flowing, pressurized products. The risk of burn through and in particular, the susceptibility to cracking are greatly increased by the rapid cooling rates associated with the high heat sink effect of the flowing gas and in turn can result in excessive hardening of the heat affected zone in ferritic steels. Edison Welding Institute developed new criteria for safe hot tap welding procedures on all ferritic steels. Their approach is based on correlating field measurements of the ability of the pipe to conduct heat (i.e., its heat-sink capacity) to the cooling rate of the weld. Laboratory welding trials with simulated branch and sleeve connections on live pipelines containing natural gas were used to validate the new criteria. The results indicate that structurally sound hot tap repairs can be made with a high level of confidence.
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