Variable Airflow Management with Direct Expansion Computer Room Air Conditioning (DX-CRAC) Units in Data Centers
Author: Dennis Symanski
Publisher:
Published: 2013
Total Pages: 64
ISBN-13:
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Optimum Cooling of Data Centers
Author: Jun Dai
Publisher: Springer Science & Business Media
Published: 2013-11-20
Total Pages: 196
ISBN-13: 1461456029
DOWNLOAD EBOOKThis book describes the use of free air cooling to improve the efficiency of, and cooling of, equipment for use in telecom infrastructures. Discussed at length is the cooling of communication installation rooms such as data centers or base stations, and this is intended as a valuable tool for the people designing and manufacturing key parts of communication networks. This book provides an introduction to current cooling methods used for energy reduction, and also compares present cooling methods in use in the field. The qualification methods and standard reliability assessments are reviewed, and their inability to assess the risks of free air cooling is discussed. The method of identifying the risks associated with free air cooling on equipment performance and reliability is introduced. A novel method of assessment for free air cooling is also proposed that utilizes prognostics and health management (PHM). This book also: Describes how the implementation of free air cooling can save energy for cooling within the telecommunications infrastructure. Analyzes the potential risks and failures of mechanisms possible in the implementation of free air cooling, which benefits manufacturers and equipment designers. Presents prognostics-based assessments to identify and mitigate the risks of telecommunications equipment under free air cooling conditions, which can provide the early warning of equipment failures at operation stage without disturbing the data centers' service. Optimum Cooling for Data Centers is an ideal book for researchers and engineers interested in designing and manufacturing equipment for use in telecom infrastructures.
Air Flow Management in Raised Floor Data Centers
Author: Vaibhav K. Arghode
Publisher: Springer
Published: 2015-11-23
Total Pages: 90
ISBN-13: 3319258923
DOWNLOAD EBOOKThe Brief discuss primarily two aspects of air flow management in raised floor data centers. Firstly, cooling air delivery through perforated tiles will be examined and influence of the tile geometry on flow field development and hot air entrainment above perforated tiles will be discussed. Secondly, the use of cold aisle containment to physically separate hot and cold regions, and minimize hot and cold air mixing will be presented. Both experimental investigations and computational efforts are discussed and development of computational fluid dynamics (CFD) based models for simulating air flow in data centers is included. In addition, metrology tools for facility scale air velocity and temperature measurement, and air flow rate measurement through perforated floor tiles and server racks are examined and the authors present thermodynamics-based models to gauge the effectiveness and importance of air flow management schemes in data centers.
Data Centers HVAC DESIGN
Author: Charles Nehme
Publisher: Charles Nehme
Published: 2022-02-22
Total Pages: 37
ISBN-13:
DOWNLOAD EBOOKThis book discusses HVAC design criteria for Data centres. I have written it with the knowledge of my 15 years of involvement in Data centers on every continent. I have worked on the construction and implementation of Data centers, on the facilities maintenance and operations and many years as Quality Assurance Manager. I have kept it simple yet concise. #datacenters #book #engineering #hvac #cooling #it
Computer Room Air Conditioners
Author: Charles Nehme
Publisher: Charles Nehme
Published:
Total Pages: 35
ISBN-13:
DOWNLOAD EBOOKIntroduction In today's data-driven world, the importance of maintaining stable and controlled environments for critical infrastructure cannot be overstated. Data centers, server rooms, telecommunications facilities, and industrial control centers all rely on precise temperature and humidity regulation to ensure the reliable operation of sensitive equipment and protect valuable data. At the heart of these control systems lies the crucial role of CRAC units, or Computer Room Air Conditioners. The Significance of CRAC Units CRAC units are specialized HVAC systems designed specifically to meet the stringent cooling requirements of critical environments. These units are typically compact and modular, making them well-suited for installation in confined spaces. They operate using a refrigeration cycle, absorbing heat from the room and expelling it to the outside environment, thereby maintaining a controlled climate within the facility.
Precision Cooling: Optimizing Climate Control in Critical Environments
Author: Charles Nehme
Publisher: Charles Nehme
Published:
Total Pages: 54
ISBN-13:
DOWNLOAD EBOOKIn the contemporary landscape of technology and industry, the need for controlled environmental conditions transcends mere comfort, becoming critical for the operational integrity of numerous high-stakes fields. Precision cooling stands as a pillar in this arena, ensuring that sensitive environments—ranging from bustling data centers to meticulous laboratory settings—maintain the necessary conditions for optimal performance and reliability. The advent of precision cooling technologies marks a pivotal evolution from traditional cooling methods, addressing the nuanced demands of modern electronic and industrial equipment susceptible to damage from even minor fluctuations in temperature or humidity. This book, "Precision Cooling: Ensuring Operational Excellence in Critical Environments," aims to provide a comprehensive exploration of precision cooling systems. It delves into the technical underpinnings, practical applications, and strategic importance of maintaining stringent environmental controls. Our journey will navigate through the core concepts of temperature, humidity, and airflow management, extending into the sophisticated technologies that enable such precise regulation. We begin by laying a foundation with a historical perspective on the evolution of cooling technologies, leading up to the sophisticated systems in use today. Subsequent chapters dissect the mechanisms of action, design considerations, and operational nuances of modern precision cooling systems. We delve deep into case studies from industries where precision cooling is non-negotiable, such as data centers, pharmaceuticals, and aerospace, illustrating the critical role these systems play in ensuring safety, efficiency, and sustainability. In addressing the technical facets, this book also explores the cutting-edge innovations shaping the future of precision cooling. From advancements in AI and IoT for smarter cooling solutions to the integration of green technologies for energy efficiency, the narrative is both current and forward-looking. Designed for engineers, facility managers, IT professionals, and anyone involved in managing or designing environments where precise control of cooling is essential, this book aims to be both a primer for those new to the field and a reference for seasoned professionals. By the end, readers will gain a holistic understanding of how precision cooling systems are designed, implemented, and managed, as well as the trends and challenges that will shape their future. With every chapter, "Precision Cooling: Ensuring Operational Excellence in Critical Environments" strives to equip its readers with the knowledge and insights necessary to navigate the complexities of precision cooling, fostering environments where technology and precision meet to create stability and progress.
Experimental Study on Effects of Segregated Cooling Provisioning on Thermal Performance of Information Technology Servers in Air Cooled Data Centers
Author: Ashwin Venugopal Siddarth
Publisher:
Published: 2016
Total Pages: 43
ISBN-13:
DOWNLOAD EBOOKModern Information Technology (IT) equipment are typically assumed to operate in quiescent airflow conditions in an uncontained data center facility. In this study, the multi-scaled thermal management strategies are reconsidered at the IT chassis and rack level for a containment system. For an ideal containment configuration of airflow provisioning the entirety of conditioned air provided by the Computer Room Air Conditioning (CRAC) unit would flow through the IT equipment and return back to the CRAC. But in actuality a lack of interfaced airflow distribution exists between the amount of conditioned air provisioned to the rack and the volume capacity ingested by the IT equipment thereby decreasing the efficiency of the overall cooling system. This work evaluates the thermal performance of IT servers when operating in a representative cold aisle containment system. In this study, the impact of positive and negative static pressure differentials between the inlet and exhaust of a representative rack is experimentally studied. The effect of fan proximity in the chassis layout to variations in pressure differentials is assessed. This information can be helpful in optimizing the desired static pressure set points within the room and define coupled internal fan control strategies to achieve the most energy efficient use of cooling resources.
Maximizing Use of Air-side Economization, Direct and Indirect Evaporative Cooling for Energy Efficient Data Centers
Author: Betsegaw Kebede Gebrehiwot
Publisher:
Published: 2016
Total Pages: 113
ISBN-13:
DOWNLOAD EBOOKData centers house information technology (IT) equipment such as servers and network switches which are vital for our networked modern society by providing digital data storage, data processing and connectivity. Data centers house few hundreds to tens of thousands of IT equipment that consume few kilowatt-hours to multi-megawatt-hours of electrical energy that gets dissipated as heat. IT equipment need to be properly cooled so that they operate reliably for their expected lifetime. For air cooled IT equipment, manufacturers provide heat sinks, cold plates, fans, et cetera to remove heat from the vicinity of heat dissipating components and data centers need to continuously supply cold air to the IT equipment and remove hot from the vicinity of the IT equipment. Type of cooling system used in a data center is an important factor in the overall efficiency and reliability of the data center. This dissertation focuses on use of air-side economization (ASE), direct evaporative cooling (DEC), indirect evaporative cooling (IEC), and indirect/direct evaporative cooling (I/DEC) as a way to reduce cooling cost of data centers. A test bed modular data center, which has a cooling unit that operates in ASE or two-stage I/DEC modes, and located in Dallas, TX, is primarily used for this study. Included in the study are analysis of weather data to determine what percentage of a year these cooling systems can be used, modeling of the test bed modular data center using computational fluid dynamics (CFD) tool, discussion on improvements that can be made to the cooling system and factors that limit use of ASE and I/DEC, method for improving the DEC control system, et cetera. In addition, CFD modeling of another modular data center is used to show importance of proper airflow management within cold aisle of data centers and impact of hot aisle pressurization on operating point of server fans.
Data Centers Air Conditioning Design (Common Problems & Solutions)
Author: Charles Nehme
Publisher: Charles Nehme
Published:
Total Pages: 11
ISBN-13:
DOWNLOAD EBOOKData centers are heavily dependent on HVAC systems for cooling, and any problems in the HVAC system can cause a significant disruption to the functioning of the data center. Common HVAC problems in data centers include: 1. Poor Airflow: Poor airflow can be caused by a number of factors, such as clogged filters, blocked vents, or poorly-placed supply and return ducts. Poor airflow can cause the data center to overheat, leading to hardware failure and reduced efficiency. 2. Incorrect Temperature Settings: If the temperature settings are incorrect, the data center can become too hot or too cold. This can cause hardware damage and inefficient cooling, leading to higher energy costs. 3. Leaks: Leaks in the HVAC system can cause humidity levels to rise, which can lead to condensation and corrosion of the hardware. 4. Faulty Components: Faulty components, such as bad fans or compressors, can cause the data center to become too hot or too cold, leading to hardware failure and other issues. 5. Poor Maintenance: Poor maintenance of the HVAC system can lead to a decrease in efficiency and a higher risk of system failure. Regular maintenance and inspections are essential to ensure the data center is running optimally. These are just a few of the potential HVAC problems that can occur in data centers. To prevent these problems, it is important to ensure the HVAC system is properly maintained and inspected on a regular basis.
HVAC - Variable Refrigerant Flow (VRF) Systems
Author: A. Bhatia
Publisher: CreateSpace
Published: 2014-12-06
Total Pages: 44
ISBN-13: 9781505394047
DOWNLOAD EBOOKVRF (Variable refrigerant flow) is an air-condition system configuration where there is one outdoor condensing unit and multiple indoor units. The term variable refrigerant flow (VRF) refers to the ability of the system to control the amount of refrigerant flowing to the multiple evaporators (indoor units), enabling the use of many evaporators of differing capacities and configurations connected to single condensing unit. The arrangement provides an individualized comfort control, and simultaneous heating and cooling in different zones. Currently widely applied in large buildings especially in Japan and Europe, these systems are just starting to be introduced in the U.S. The VRF technology/system was developed and designed by Daikin Industries, Japan who named and protected the term variable refrigerant volume (VRV) system so other manufacturers use the term VRF "variable refrigerant flow". In essence both are same. With a higher efficiency and increased controllability, the VRF system can help achieve a sustainable design. Unfortunately, the design of VRF systems is more complicated and requires additional work compared to designing a conventional direct expansion (DX) system. This 3 -hour quick book provides an overview of VRF system technology. Emphasis is placed on the control principles, terminology, basic components, advantages and design limitations. This course is aimed at the personnel who have some limited background in the air conditioning field and is suitable for mechanical, electrical, controls and HVAC engineers, architects, building designers, contractors, estimators, energy auditors and facility managers.The course includes a multiple-choice quiz consisting of fifteen (15) questions at the end. Learning ObjectiveAt the conclusion of this course, the reader will: * Understand the difference between multi-split air conditioning system and VRF systems;* Understand the operating principle of direct expansion split and VRF system;* Understand the concept of thermal zone;* Understand how VRF with heat recovery are different from ordinary heat pump systems;* Understand the operation of thermostatic expansion valve (TXV) and electronic expansion valve (EEV);* Understand the influence of building characteristics and load profile on selection of VRF system;* Learn the advantages and application of VRF systems;* Understand the design limitations and challenges in design of VRF systems.
