You're using an outdated browser. Please upgrade to a modern browser for the best experience.
Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort by:
Most Viewed Latest Alphabetical (A-Z) Alphabetical (Z-A)
Filter:
All Topic Review Biography Peer Reviewed Entry Video Entry
Topic Review
Hexapod Robots
The static stability of hexapods motivates their design for tasks in which stable locomotion is required, such as navigation across complex environments. This task is of high interest due to the possibility of replacing human beings in exploration, surveillance and rescue missions. For this application, the control system must adapt the actuation of the limbs according to their surroundings to ensure that the hexapod does not tumble during locomotion.
  • 1.7K
  • 25 Aug 2021
Topic Review
Texturing Methods of Abrasive Grinding Wheels
Creating textures on abrasive wheels is a strategy that allows a significant improvement in grinding operations. The reduction of the internal stresses in the workpiece and the temperature during the grinding operation generates an increase in the dimensional accuracy of the workpiece and a longer tool life. Textured abrasive wheels can be produced in many different ways. Depending on the processing method, the dimensional accuracy of the tool and its applicability is changed. 
  • 1.6K
  • 28 Nov 2022
Topic Review
Factors Affecting FIV in Internal Two-Phase Flow
Two-phase flow is commonly encountered in various engineering systems. Momentum fluctuation in two-phase flow can create undesirable and destructive vibrations. These vibrations have attracted considerable attention and are known as flow-induced vibrations (FIV). Different factors effecting FIV is two phase flow is discussed here in detail.
  • 1.6K
  • 13 Oct 2022
Topic Review
Pumped Thermal Energy Storage Technology
There has been an increase in the use of renewable energy resources, which has led to the need for large-scale Energy Storage units in the electric grid. Compressed Air Energy Storage (CAES) and Pumped Hydro Storage (PHES) are the main commercially available large-scale energy storage technologies. Among the in-development, large-scale Energy Storage Technologies, Pumped Thermal Electricity Storage (PTES), or Pumped Heat Energy Storage, stands out as the most promising due to its long cycle life, lack of geographical limitations, the absence of fossil fuel streams, and the possibility of integrating it with conventional fossil-fuel power plants. There have been a number of PTES systems proposed using different thermodynamic cycles, including the Brayton cycle, the Rankine cycle, and the transcritical Rankine cycle.
  • 1.6K
  • 14 Aug 2023
Topic Review
Hybrid Ejector-Absorption Refrigeration Systems
Absorption Refrigeration Systems (ARS) are potential alternatives to direct expansion (DX) refrigeration systems. This review focuses on the incorporation of an ejector into absorption refrigeration cycles to constitute Hybrid Ejector-Absorption Refrigeration Systems (HEARS). The ejector adds several advantages to the absorption refrigeration systems depending on its location in the cycle. The two prevalent configurations of HEARS are Triple pressure level (TPL-HEARS), and Low Pressure Condenser (LPC-HEARS). Previous studies revealed the preference of the later configuration as it allows lower circulation ratios, enhances the refrigeration effect, and could achieve a COP up to 1. Moreover, LPC configuration is suitable with single, double, and variable effect absorption systems with a COP of above unity. In turn, the TPL-HEARS notably enhances the absorption process particularly when a variable geometry ejector is utilized. This configuration could obtain a COP around 1.1, but only with high-density refrigerant vapor. Lately, to attain the advantages of both configurations; some studies investigated the viability of adding two ejectors to the cycle. This paper meticulously reviews investigations conducted on the emerging dual ejectors-absorption refrigeration technology. This paper reveals the general performance trend and the maximum attainable COP by each type of hybrid ejector-absorption refrigeration system. DEARS and Ejector-driven absorption refrigeration systems (ED-ARS) could achieve COP that ranges between 1.2 and 1.46. The use of a flash tank and a RHE is essential in NH3/H2O HEARS. At high generator temperatures of (120 – 170 °C), DEARS was found to be the system with the less complexity and best performance. Nevertheless, the performance of the DEARS might drop significantly if the heat source temperature is fluctuating. Thence, the variable effect HEARS is considered the best alternative. The capability of HEARS to be integrated with different power generation cycles is also highlighted. Finally, the review presents possible future research opportunities to improve the absorption refrigeration technology.
  • 1.6K
  • 01 Nov 2021
Topic Review
Liquid Air Energy Storage Technologies
Liquid air energy storage (LAES) has gained prominence as an alternative to existing large-scale electrical energy storage solutions such as compressed air (CAES) and pumped hydro energy storage (PHES), especially in the context of medium-to-long-term storage. LAES offers a high volumetric energy density, surpassing the geographical constraints that hinder current mature energy storage technologies. The basic principle of LAES involves liquefying and storing air to be utilized later for electricity generation.
  • 1.6K
  • 08 Sep 2023
Topic Review
Non-Destructive Evaluation of Structural Composite Materials
The growing demand and diversity in the application of industrial composites and the current inability of present non-destructive evaluation (NDE) methods to perform detailed inspection of these composites has motivated this comprehensive review of sensing technologies. NDE has the potential to be a versatile tool for maintaining composite structures deployed in hazardous and inaccessible areas, such as offshore wind farms and nuclear power plants. Therefore, the future composite solutions need to take into consideration the niche requirements of these high-value/critical applications. Composite materials are intrinsically complex due to their anisotropic and non-homogeneous characteristics. This presents a significant challenge for evaluation and the associated data analysis for NDEs. For example, the quality assurance, certification of composite structures, and early detection of the failure is complex due to the variability and tolerances involved in the composite manufacturing. Adapting existing NDE methods to detect and locate the defects at multiple length scales in the complex materials represents a significant challenge, resulting in a delayed and incorrect diagnosis of the structural health. This paper presents a comprehensive review of the NDE techniques, that includes a detailed discussion of their working principles, setup, advantages, limitations, and usage level for the structural composites. A comparison between these techniques is also presented, providing an insight into the future trends for composites’ prognostic and health management (PHM). Current research trends show the emergence of the non-contact-type NDE (including digital image correlation, infrared tomography, as well as disruptive frequency-modulated continuous wave techniques) for structural composites, and the reasons for their choice over the most popular contact-type (ultrasonic, acoustic, and piezoelectric testing) NDE methods is also discussed. The analysis of this new sensing modality for composites’ is presented within the context of the state-of-the-art and projected future requirements.
  • 1.6K
  • 20 Dec 2021
Topic Review
Applications of Phase Change Materials
Appropriate measures have been taken to reduce energy requirements for cold chain applications. Thermal energy storage is an accepted method to reduce the need for electrical energy after harvesting fresh horticultural produce. The use of phase change materials (PCM) in postharvest storage, outside of a temperature-controlled environment, extends shelf life and keeps food at the ideal temperature. 
  • 1.6K
  • 03 Nov 2022
Topic Review
Micromachined Accelerometers with Non-noise Floor
This paper reviews the research and development of micromachined accelerometers with a noise floor lower than 1 µg/√Hz. Firstly, the basic working principle of micromachined accelerometers is introduced. Then, different methods of reducing the noise floor of micromachined accelerometers are analyzed. Different types of micromachined accelerometers with a noise floor below 1 µg/√Hz are discussed. 
  • 1.6K
  • 09 Jul 2021
Topic Review
Signal Processing of Pulsed Thermography for Enhanced Detectability
Non-destructive testing (NDT) is a broad group of testing and analysis techniques used in science and industry to evaluate the properties of a material, structure, or system for characteristic defects and discontinuities without causing damage. Recently, infrared thermography is one of the most promising technologies as it can inspect a large area quickly using a non-contact and non-destructive method. Moreover, thermography testing has proved to be a valuable approach for non-destructive testing and evaluation of structural stability of materials. Pulsed thermography is one of the active thermography technologies that utilizes external energy heating. However, due to the non-uniform heating, lateral heat diffusion, environmental noise, and limited parameters of the thermal imaging system, there are some difficulties in detecting and characterizing defects.
  • 1.6K
  • 17 Jan 2022
Topic Review
Powder Bed Fusion Process
The ability to manufacture parts with complex geometry by sending a model from CAD directly to the manufacturing machine has attracted much attention in the industry, driving the development of additive manufacturing technology. However, studies have shown that components manufactured using additive manufacturing technology have several problems, namely high tensile residual stresses, cracks, and voids, which are known to have a major impact on material performance (in service).
  • 1.6K
  • 24 Oct 2023
Topic Review
Nanofluid Preparation and Stability
The advent of nanotechnology has brought about significant technological advancements in many fields of study. The birth of nanofluids as an advanced thermal transport media in the area of thermal management is a laudable and notable feat. Nanofluids (mono and hybrid nanofluids) have been extensively researched and established to be better than conventional thermal transport media due to their enhanced thermophysical and convective properties.
  • 1.6K
  • 31 Jan 2023
Topic Review
Heat Exchanger Design Methods
Finned tube heat exchangers are used in many technological applications in both civil and industrial sectors. Their large-scale use requires a design aimed at reaching high thermal efficiency as well as avoiding unnecessary waste of resources in terms of time and costs. Multi-scale methods are very flexible and suitable for different heat exchanger geometries and working conditions because they integrate analytical methods’ benefits with more accurate numerical approaches. The hybrid method is an alternative design procedure based on an algorithm that uses a multi-scale method, based on data from either analytical, numerical, or experimental investigations.
  • 1.6K
  • 12 Apr 2023
Topic Review
Methods for Residual Stress Testing
This entry introduces several commonly used residual stress measurement methods.
  • 1.5K
  • 29 Oct 2020
Topic Review
ML-Based LIB Fault Diagnosis
Fault detection/diagnosis has become a crucial function of the battery management system (BMS) due to the increasing application of lithium-ion batteries (LIBs) in highly sophisticated and high-power applications to ensure the safe and reliable operation of the system. 
  • 1.5K
  • 16 Dec 2021
Topic Review
Cool Roofs
The use of white roofing material is a suggestion because of its cooling, evaporative and efficiency characteristics compared to traditional black roofing materials. Many research studies have shown that the darker roofing surfaces that are prevalent in many urban areas actually can increase temperature by 1 to 3 degrees Celsius to the environment surrounding these urban areas. Additionally, improved temperature control and heat reflection also work to reduce the energy requirements for the interior spaces of the structures that have white roofing surfaces. The white or lighter colored roofs tend to reflect a part of the solar radiation that strikes the roof’s surface. Consequently, one might believe that white roofing material would be commonplace and especially so within emerging economies. Yet, this is hardly the case at all. 
  • 1.5K
  • 25 Oct 2022
Topic Review
Fracture Toughness of FRP Composites Using Short Fibers
Fiber-reinforced plastic (FRP) composite laminates are widely used in the aerospace field, automotive industry, wind power generation, and civil infrastructure because of their lightweight and relatively high strength characteristics. Interlaminar fracture toughness (ILFT) is a quantitative measure of the ability of composite laminates to resist crack extension and an estimate of material toughness. 
  • 1.5K
  • 31 May 2022
Topic Review
Diesel Engines Emissions Reduction
Compression ignition engines play a significant role in the development of a country. They are widely used due to their innate properties such as high efficiency, high power output, and durability. However, they are considered one of the key contributors to transport-related emissions and have recently been identified as carcinogenic. Thus, it is important to modify the designs and processes before, during, and after combustion to reduce the emissions to meet the strict emission regulations.
  • 1.5K
  • 13 Apr 2021
Topic Review
Improving Dust Collector Efficiency for Pneumatic Conveying
A dust collection system removes the dust contents of an industrial environment to provide a comfortable work environment and meet safety and health regulations. The system takes the dust particles and carries them outside for disposal or reuse possibilities.
  • 1.5K
  • 28 Feb 2022
Topic Review
Influence of 3D Printing Parameters on FFF Prints
The advancement in 3D printing techniques has raised the hope to use additively manufactured parts as final products in various industries. Due to the layer-by-layer nature of AM parts, they are highly susceptible to failure when they are subjected to fatigue loading. This entry provides a detailed account of the influence of 3D printing parameters on the fatigue properties of parts manufactured by fused filament fabrication (FFF). Existing standards for fatigue testing of polymers and their limitation for 3D-printed parts are discussed. In addition, the cyclic behaviour of polymers is reviewed, and the impact of 3D printing parameters on the mechanical behaviour of FFF parts under tensile, compressive, flexural, and bending fatigue is investigated according to the published results in the literature. Finally, a summary of the works undertaken and suggestions for future research are provided. The influence of 3D printing parameters on the fatigue performance of prints can be different from that seen in the case of static loading and strongly depends on the fatigue loading type. While cross-over infill patterns, higher infill density, and higher layer height favour achieving higher fatigue strength in all loading types, raster orientation is best to be aligned parallel to the tensile loads and perpendicular to the compressive, flexural, and bending forces. In the case of tensile and flexural loading, Y build orientation yields the best result. Finally, print velocity was found to be less significant compared to other parameters, implying that it can be set at high values for faster printing.
  • 1.5K
  • 10 Feb 2023
  • Page
  • of
  • 18
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of COVID-19
Encyclopedia of Engineering
Encyclopedia of Social Sciences
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Academic Video Service
Feedback