bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Generalized and Inversed Vapor Pressure Correlation Applied to Experimental/Smoothed Data for Pure Fluids
Authors: Rogdakis E. D. 
Published: December 2021

Abstract
In the present work a new vapor pressure equation is proposed which combines all advantages of the most significant equations, i.e.
• As Wagner equation, it is capable of representing the correct shape of the vapor pressure curve for expanded ranges of the temperature.
• As Antoine equation, it can be inversed expressing boiling point as a function of the pressure.
• As in Lee-Kesler and two reference fluids methods, it has been found a very useful and more accurate correlation in terms of the reduced temperature.
Another advantage of the new equation is its fundamental, single and generalized form for all substances.
Extensive test of the proposed equation using experimental/smoothed data for twenty-two pure fluids indicates that it normally predicts very well the vapor pressure from the critical down to the triple point. (Overall Average Mean and Overall Average Max. Error 0.0526% and 0.1195% respectively).
A predictive method too for the triple point pressure has been developed (Mean Error 1.1553%).
The Effect of Humidity on the Thermodynamic Behaviour of Atmospheric Air
Authors: Kouremenos D. A. , Kakatsios X. K. , Krikkis R. N. 
Published: December 2021

Abstract
The present work considers the thermodynamic behaviour of moist air as a function of the state variables temperature, density and humidity ratio. Moist air is treated as an ideal mixture which is composed of two real gases, air and steam. The state functions of the mixture are expressed using the corresponding explicit relations of the two species from which the three isentropic exponents describing the real gas isentropic change are calculated. Saturated conditions are determined by solving the Vapour Liquid Equilibrium problem for real water. Numerical results show the effect of humidity as well as the effect of pressure on the thermodynamic behaviour of atmospheric air (such as the three isentropic exponents kpρ, kTp, kTρ, the classical isentropic exponent k and the velocity of sound) for a wide range of temperatures and pressures. Furthermore the isentropic change is approximated by explicit relations having mathematical forms similar to those of the ideal gas but with different constants and exponents. The obtained accuracy is remarkable, being better than 0.32%. In this way the isentropic change, of moist air can be computed by simple explicit relations having as independent variable the Mach number and the humidity ratio. The effects of humidity are examined on certain cases of practical interest such as the critical state (M = 1), the impulse function and the mass flow rate.
Combustion Quasi-Two Zone Predictive Model for Dual Fuel Engines
Authors: Abd Alla G. H. , Soliman H. A. , Badr O. A. , Abd Rabbo M. F. 
Published: December 2021

Abstract
A quasi-two zone predictive model developed in the present work for the prediction of the combustion processes in dual fuel engines and some of their performance features. Methane is used as the main fuel while employing a small quantity of liquid fuel (pilot) injected through the conventional diesel fuel system. This model emphasizes the effects of chemical kinetics activity of the premixed gaseous fuel on the combustion performance, while the role of the pilot fuel in the ignition and heat release processes is considered. A detailed chemical kinetic scheme consists of 178 elementary reaction steps and 41 chemical species is employed to describe the oxidation of the gaseous fuel from the start of compression to the end of expansion process. The associated formation and concentrations of exhaust emissions are correspondingly established. This combustion model is able to establish the development of the combustion process with time and the associated important operating parameters such as pressure, temperature, rates of energy release and composition. Predicted values for methane operation show good agreement with corresponding previous experimental values over a range of operating conditions mainly associated with high load operation.
Development of Miller Cycle Gas Engine for Cogeneration
Authors: Tsukida Nobuaki , Okamoto Kazuhisa , Abe Takashi , Takemoto Toru 
Published: December 2021

Abstract
We have developed a 300 kW gas engine cogeneration system for practical use that uses natural gas. Using a gas engine operated under conditions with an excess air ratio λ = 1 that is able to use a three way catalyst to purify the exhaust gases, we were able to achieve high efficiency through the application of the Miller Cycle, as well as a low NOx output. In terms of product specifications, we were able to achieve an electrical efficiency of 34.2% and a heat recovery efficiency of 49.3%, making an overall efficiency of 83.5% as a cogeneration system.
Optimal Capacity Planning of a Brewery’s Energy Supply Plant Using its Simulation Model Based on LabVIEW
Authors: Shiba Takashi , Ito Koichi , Yokoyama Ryohei , Sakashita Shigeru 
Published: December 2021

Abstract
An optimal capacity planning method is proposed for a brewery’s energy supply plant from the viewpoint of long-term economics. The proposed method is composed of two hierarchical stages. At the outer stage, equipment capacities and utility maximum demands of the brewery’s energy supply plant are optimized together with values of control parameters of thermal storage tanks by the sequential linear programming method. At the inner stage, the equipment operation of the plant for given energy demands is simulated on the basis of control rules using LabVIEW. Both two stages are interconnected so as to be compatible with each other. Through a numerical study, it is investigated how equipment capacities, utility maximum demands, and control parameters of thermal storage tanks influence the long-term economics of the plant. From the results, it is ascertained that the long-term economics can be improved using the proposed method.
Investigation and Evaluation of Steam Hammer Occurring During Boiler Blowdown Process
Authors: Park Hyunjae , Richardson Dave , Stansfield Tod , Tompkins Gene , Molvie Peter 
Published: December 2021

Abstract
When a reservoir (vessel) discharges through pipes, and the flow is regulated by a valve(s), a metastable and/or critical flow may occur. The metastable flow may be due to choking of the flow or flashing of the fluid (in the pipe or through the valve). These phenomena are highly transient and involve sudden changes in fluid velocity, leading to large pressure changes which manifest themselves as pressure waves, across which there are discontinuities in pressure and velocity. These relatively strong pressure pulses and waves propagate throughout the system and may damage some of the system components. Pressure waves of this general nature are often called steam (or water) hammer. A major issue in the boiler industry is damage to boiler safety devices due to such phenomena, which sometimes occurs during the boiler blowdown process. The blowdown process is similar to the discharge through pipes and valves as described above. In this paper, a one-dimensional analytical model is developed to predict the intensity of steam hammer in terms of relevant parameters.
Second Law Analysis of Separation Processes of Mixtures
Authors: Çengel Yunus A. , Çerçi Yunus , Wood Byard 
Published: December 2021

Abstract
Mixing and separation processes are commonly encountered in a wide range of industries in practice. Separation processes require a work (more generally, exergy) input, and minimizing this required work input is an important part of the design process of separation plants. The presence of dissimilar molecules in a mixture affect each other, and therefore the influence of composition on the properties must be taken into consideration in any thermodynamic analysis. Below we first analyze the general mixtures and the mixing processes, with particular attention to ideal solutions, and determine the entropy generation and the corresponding exergy destruction. We then consider the reverse process of separation, and determine the minimum (or reversible) work input needed for separation. The results presented can readily be used in the calculation of minimum work input and the determination of the second law efficiency of separation processes.
Thermodynamic Analysis and Optimisation of Mixed Fluid Turbine Power Plants
Authors: Belli M. , Stumbo M. , Vinarova D. 
Published: December 2021

Abstract
This paper discusses the thermodynamics of power cycles where steam or water are mixed with air to improve the performance of stationary gas turbine cycles. A general computer simulation program is presented; several components (compressor, combustor, turbine, recovery boiler, saturator, recuperator, inter-cooler, after-cooler) are modelled obtaining a transfer function between in-coming and out-coming fluids.
Coupled with this simulation program, an optimisation is carried out using a decomposition strategy based on the second law of thermodynamic and a concept for costing the components of the cycles. A large number of decision variables can by optimised with enhanced convergence to an optimum.
As results, a large number of simulations and optimisations are performed for three different plants (STIG, HAT and a cycle with water injection both in the compressor and in the combustor). A wide number of comparisons shows the difference between the cycles and the power level at which each plant gives the lowest exergoeconomic costs.
Total Equivalent Resource Consumption of Residential Heating Systems
Authors: Reistad Gordon M. , Moungkeow Thanat 
Published: December 2021

Abstract
This paper reports on an evaluation of several energy conversion systems utilizing the Total Equivalent Resource Exergy (TERE) method (Zhang and Reistad, 1998). The systems are residential gas furnace and heat pump systems. The TERE method uses exergy as an overall evaluation parameter for energy conversion systems which combines energy and environmental resource (global warming) consumption. The method evaluates the exergy of the fuel, the exergy for the material in the system and the exergy required to recover the total global warming impact caused by CO2 equivalent emissions. This is done for both the energy conversion and production systems. The results illustrate comparisons of the systems for their consumption and their total lifetime impact including global warming.
Results of these comparisons, with the assumptions made, indicate that the high efficiency natural gas furnaces have less lifetime impact (greater efficiency) in satisfying a specified heating load as compared to low efficiency natural gas fueled furnaces. Some very high-efficiency furnaces with large blowers may, however, have greater lifetime impact than units that have moderately high efficiencies and smaller blowers. Relative to the three heat pump systems considered, the high efficiency gas furnaces were evaluated to have less lifetime impact than the air-source and direct-expansion, ground-source heat pumps, but more lifetime impact than the vertical ground-source heat pump. The annualized TERE values of the high efficiency gas furnaces are about 94 GJ compared to the greater than 100 GJ of the first two types of heat pumps. The vertical ground-source heat pump has the lowest annualized TERE value of 88 GJ.
These comparisons should be viewed in light of the following:
• The CO2 recovery exergy assumed here is not a precise value. This recovery exergy does have a major influence on TERE.
• The energy requirement and heat pump performance taken in this evaluation is based on one certain location in the U.S., a Northwest region, and the results do not necessarily apply to other locations and climate patterns.
• The accurate evaluation of scarce information such as weight and material of each component in the energy conversion systems is difficult; the information used in this evaluation is based on estimations.
Comparison of Various Methods to Represent Energy Features of a Total System
Authors: Ishida Masaru , Yamamoto Masashi 
Published: December 2021

Abstract
Comparison of various methods for analyzing characteristic features of a total system is demonstrated. Process flow diagram (PFD) shows streams and main apparatuses schematically. Hence we can imagine system configuration. However, it gives no quantitative information. Energy flow and exergy flow diagrams, respectively, show information about the first law and the second law of thermodynamics. The advantages of these diagrams disappear for a large and complex system.
Then we propose a new diagram, a process flow diagram with process vectors. Base frame of this diagram is the same of the PFD, but information about H and ε of important streams and ΔH and Δε for each change of substances is represented by drawing process vectors. And features of exergy loss are clearly depicted by their combination.
Development of a Simulation Tool for Gas Co-Generation Systems
Authors: Murata Yukimaro , Horizoe Tomohiko , Oka Masahiro 
Published: December 2021

Abstract
Tokyo Gas developed a new simulation tool for gas co-generation systems. We expect that this tool will help us in both developing co-generation components such as absorption chillers to utilize the waste heat of co-generation and making suggestion for optimum co-generation engineering.
This simulation tool is superior to other simulation tools in simulation result accuracy and availability to complicated co-generation systems. It was achieved by new calculation logic and detailed description of features of co-generation components. This simulation tool can evaluate energy consumption and running cost of simulation models for buildings with co-generation systems.
Tokyo Gas has used this simulation tool in development of three new gas absorption chiller heaters with auxiliary waste heat recovery and for energy consumption evaluation of many buildings with co-generation systems, which are so complicated that other simulation tools are not available.
Laser-Based Transient Surface Acceleration of Thermoelastic Layers
Authors: Cetinkaya Cetin , Li Chen , Wu Cunli 
Published: December 2021

Abstract
The effectiveness of traditional surface cleaning methods, such as ultrasonically induced fluid flow, vibrational methods, centrifugal techniques, is limited to particles that require surface acceleration lower than 107m/s2. For sub-micron particles, a higher level surface acceleration is needed. In the current work, based on the generalized dynamic theory of thermoelasticity, a transfer matrix formulation including the second sound effect is developed for a layer. The transfer matrix for axisysmmetric wave propagation in the thermoelastic layer is obtained by adopting integral transforms. The second sound effect is included to eliminate the immediate arrival of thermal waves. A transfer function formulation for calculating the accelerations is developed for transient analysis. In the current work, only the surface acceleration due to transient thermoelastic wave propagation is under investigation.
Effects of Exciting Frequency and Grain Size in Ultrasonic NDE of Concrete
Authors: Ju J. W. , Weng L. , Liu Y. 
Published: December 2021

Abstract
This investigation focuses on experimental study of the effects of the exciting frequency and the grain (aggregate) size upon the ultrasonic P-wave velocity and the wave attenuation characteristics such as the peak-to-peak amplitude and dominant frequency-shift when performing the ultrasonic nondestructive evaluation of concrete. Furthermore, this presentation studies the extent of wave attenuation as influenced by different grain (aggregate) sizes with or without the well-distributed embedded micro-damage under different exciting frequencies. The damage index or damage assessment of concrete is certainly linked to the reduction in the ultrasonic P-wave velocity, the reduction in the peak-to-peak amplitude response, and the increase in frequency-shift through a damaged concrete specimen.
In this study, we cast concrete cylinders with five different aggregate sizes in our laboratory, including some mortar samples without coarse aggregates. In addition, small styrofoam particles are mixed into the control samples in all batches to simulate microvoids in damaged concrete. The exciting frequency ranges from a low frequency at 50 kHz to a demium frequency at 300 to 400 kHz to demonstrate the frequency effect upon the ultrasonic NDE of concrete for each batch. The grain size also affects the concrete microstructure and influences the propagation and attenuation of ultrasonic waves through undamaged and damaged concrete specimens.
Elastodynamic Response of a Chain of Particles
Authors: Kinra Vikram K. , Henderson Benjamin K. , Maslov Konstantin 
Published: December 2021

Abstract
The reflection of an axially incident plane longitudinal wave from a linear chain of identical spherical inclusions embedded in a viscoelastic matrix is measured. The reflection spectrum is characterized by a sequence of resonances corresponding to the Floquet condition, where an integral number of half-wavelengths in the matrix spans the interparticle distance.
The Dynamic Electromechanical Behaviour of Advanced Composites Incorporating Piezoelectric Fibres
Authors: Wang X. D. 
Published: December 2021

Abstract
This paper provides a comprehensive treatment of the electromechanical behaviour of fibre reinforced piezoelectric composites under steady-state dynamic loading. The composites are modelled as two-dimensional media with interacting piezoelectric inhomogeneities. The original problem is decomposed into single inhomogeneity subproblems, which are solved by using Fourier expansions. The solutions of these subproblems are then summed up in a consistent manner to provide a system of linear algebraic equations, from which the dynamic electromechanical field in the composites can be determined. Numerical examples are provided to show the effect of the interaction between piezoelectric fibres, the material mismatch and the loading frequency upon the dynamic local stress field and electrical response of the composites.
Equivalent Composite Laminated Beams With Various Elastic Constitutive Models
Authors: Sheinman Izhak , Frostig Yeoshua 
Published: December 2021

Abstract
Equivalent one-dimensional constitutive models of composite laminated beams with shear deformation are derived from the classical laminate two-dimensional using first-order shear deformable theory. The present cylindrical bending constitutive models can be used — with much greater accuracy than their well known plane-strain and plane-stress counterparts — as upper and lower bounds, to one of which the behavior tends depending on the width-to-length ratio; this aspect was investigated and results are presented.
Reliability Analysis of Flip Chip on Board Assemblies Using No-Flow Underfill Materials
Authors: Thorpe Ryan , Baldwin Daniel F. 
Published: December 2021

Abstract
As a concept to achieve high throughput low cost flip chip on board (FCOB) assembly, a process development activity and reliability assessment is underway, implementing next generation flip chip processing based on large area underfill printing/dispensing, integrated chip placement and underfill flow, and simultaneous solder interconnect reflow and underfill cure. Reported in this work is the assembly of a series of test vehicles to evaluate the reliability of no-flow underfill materials. The reliability performance of four underfill materials is evaluated using six test vehicles. Accelerated reliability tests performed on the test vehicles included liquid/liquid and air/air thermal cycling, autoclave, and J-STD-020 Level 3 preconditioning. No-flow underfill materials tested in this work have demonstrated the ability to survive in excess of 1000 cycles of liquid/liquid thermal shock, survive more than 100 hours of autoclave, and pass J-STD-020 Level 3 preconditioning.
A Performance & Manufacturability Evaluation of Bump Chip Carrier Packages
Authors: Mercado Lei L. , Sarihan Vijay , Fiorenzo Russell 
Published: December 2021

Abstract
Bump Chip Carrier® (BCC) is an attractive solution to the demand of high packaging density of low I/O-count packages. It offers low cost, high performance, and much smaller package size than Quad Flat Packages (QFP). Electrically, BCC offers significant performance advantage as a function of frequency. It also has customizable configurations. In this paper, an extensive finite element thermomechanical analysis has been conducted to evaluate the reliability of BCC packages during thermal cycling. The effect of a variety of parameters on package reliability was evaluated, including board thickness, package size mold material, solder paste thickness, and terminal height. The solder reliability of corner leads vs. inner leads, as well as square leads vs. rectangular leads was also investigated. Then some manufacturing issues were studied. During manufacturing, molded panels for BCC packages are undergoing significant warpage. Two types of mold designs were compared through 3D finite element analysis. A variety of mold compound materials were evaluated. The most effective way to reduce warpage was suggested.
Artwork Scaling Factor for Inner Layers in Multi-Layer Board Manufacture
Authors: Christofferson Owen , Sahay Chittaranjan 
Published: December 2021

Abstract
Demands for high-density multi-layer printed circuits continue to push the limits of common materials and process capabilities. Materials and processes that can improve current manufacturing tolerances will improve yields on current designs as well as free up printed circuit board real estate for increased circuit densities. Achieving these improvements requires an understanding of all the variables that contribute to inner layer feature-to-drilled hole registration and how tolerances stack up to an overall capability. These variables include both material types and process parameters. This paper discusses the variables that affect overall registration capabilities, presents a technique for predicting artwork scaling factors.
Performance of Thermal Enhancements in Chip on Flex
Authors: Miller Gary , Sahay Chittaranjan 
Published: December 2021

Abstract
The paper describes the development of encapsulated multiple chip on flex (COF) as Industry Common Building Blocks (CBB) as an economic alternative to high cost Application Specific Integrated Circuits (ASIC). Lockheed Martin/ General Electric developed the high density interconnect (HDI) structure used in these modules. The successful implementation of such CBB has been demonstrated in a F414 FADEC (Full Authority Digital Engine Control). The paper describes the construction of these COF CBB modules and their thermal performance with several thermal enhancement techniques.
Stability of Elastic Half-Spaces by an Energy Method
Authors: Chen Yi-chao , Wheeler Lewis T. 
Published: December 2021

Abstract
An energy stability criterion is used to study the stability of deformations of a compressible elastic half-space. A minimization problem is formulated in an unbounded domain, and the first and second variation conditions are derived for this problem. Algebraic stability conditions are derived for general compressible isotropic materials, as well as for neo-Hookean class of Hadamard materials.