Actual Design Data Research Articles

Determining effective sampling frequencies for transient pressure events in water distribution systems optimal sampling for WDS transients

This study introduces a novel methodology for determining the optimal frequency for pressure data acquisition in water distribution systems (WDSs) in response to transient-flow events such as pipe ruptures. By leveraging actual design and operational data, we simulated potential rupture scenarios and their resultant pressure wave patterns through transient-flow analysis. Harmonic series modeling was used to identify significant periods that closely replicate the observed pressure-wave time series. This allowed the derivation of recommended data acquisition intervals tailored to each monitoring site within the network. The proposed approach facilitates comprehensive analysis of all possible hydraulic shock scenarios, which can provide insights into both the existing monitoring infrastructure and strategic planning in the design phase of the WDS. Although the methodology focuses on rupture events, its application can extend to various water-quality indicators and flow rates, albeit with consideration of their typically static behavior.

Techno‐economic comparison of amine regeneration process with heat‐stable amine salt reclaiming units

AbstractMost factories employ an amine gas sweetening process to remove sulfur compounds. During this process, heat‐stable amine salt (HSAS) is generated, which reduces process efficiency. Ion exchange resin and electrodialysis reclamation methods are employed for HSAS removal. However, the equipment cost, electricity, water, and raw material consumption of each unit vary according to the amount of HSAS reclaimed; thus, it is necessary to consider the cost. In this study, we compared the techno‐economic aspects of the amine regeneration process for individual HSAS reclaiming units, developed process models to predict operation costs, and verified our simulation results by comparing actual operation and design data. The proposed mathematical models can be employed to calculate various costs incurred during amine regeneration with HSAS reclaiming units. The economic crossover point is derived at 36.6111 kg‐mol/d by utilizing the models. This enables economically feasible units to be identified based on the amount of HSAS reclaimed.

The Impact of Changes in Exhaust Temperature on the Power Output and Heat Rate of a Gas Turbine with a Capacity of 238 MW

The exhaust temperature parameter is one of the parameters that need to be considered in maintaining the performance of the gas turbine. The purpose of this study is to analyze the effect of changes in exhaust temperature on power output and heat rate. The data used is the actual design data of the M701 gas turbine. This data is used in building the model using the GateCycle software. The modeling simulation results are then validated using the actual design data. To see the impact of changes in exhaust temperature, data from the latest gas turbine performance results are used. This study concludes that changes in exhaust temperature parameters of 1OC have an impact on changes in power output of 0.273% and heat rate of 0.047%.

Optimum Design of Liquified Natural Gas Bi-lobe Tanks using Finite Element, Genetic Algorithm and Neural Network

A comprehensive set of ten artificial neural networks is developed to suggest optimal dimensions of type ‘C’ Bi-lobe tanks used in the shipping of liquefied natural gas. Multi-objective optimization technique considering the maximum capacity and minimum cost of vessels are implemented for determining optimum vessel dimensions. Generated populations from a genetic algorithm are used by Finite Element Analysis to develop new models and find primary membrane and local stresses to compare with their permissible ranges using PYTHON coding. The optimum design space is mathematically modeled by training ten artificial neural networks with design variables generated by the Taguchi method. The results are compared with actual design data and the 93% achieved accuracy shows the precision of the developed design system.

An exploratory research on performance improvement of super-large natural draft wet cooling tower based on the reconstructed dry-wet hybrid rain zone

The ambient cold air cannot reach the center area of the super-large natural draft wet cooling towers (S-NDWCTs) due to the large diameter and the large water droplets resistance in the rain zone. In order to solve this issue, the reconstructed dry-wet hybrid rain zone was proposed to improve the performance of S-NDWCTs in this paper. Some split-flow plates were arranged inside the rain zone which can divide the conventional rain zone into the dry zones and wet zones, and then produced the dry-wet hybrid rain zone. The 3D numerical model of S-NDWCTs was established and validated by the actual design data, and then the ventilation and thermal performance of the S-NDWCTs with the reconstructed dry-wet hybrid rain zone were investigated. The numerical simulation results demonstrated that, after adopting the reconstructed dry-wet hybrid rain zone, the airflow velocity inside the tower becomes larger significantly, and the high temperature areas of both the moist air and the circulating water in the central area of the tower disappear. Additionally, by comparing with the S-NDWCTs with a conventional rain zone, it was discovered that, under the conditions of split-flow plates dimension parameters used in this paper, the ventilation rate and the Merkel number increase by about 2.38% and 9.89% at most, respectively; the outlet water temperature decreases by approximately 0.48 °C at most. The investigations in this paper could provide a new idea and a novel method for the in-depth energy-saving research and structural optimal design of the S-NDWCTs.

A simulation study of heat transfer in polymerization reactors

In this paper, the heat transfer in polymer reactors has been investigated. The study of various methods of heat transfer in jacketed agitated vessels and the impact of altering different agitators on the heat transfer are indicated. A computer program is developed to calculate the heat transfer parameters and the heat duty required for each case. The PVC polymer reactor in the Egyptian Petrochemical Company is chosen as a case study. This reactor is modeled by Microsoft Excel and simulated by a VISIMIX simulation program version turbulent SV. In addition, the chemical reaction is modeled by Aspen HYSYS V8, and eventually the modeling results are validated with the actual design data. Meanwhile, a comparison between various heat transfer methods is generated to set the preferable design and the topmost impeller for high heat transfer conditions. Furthermore, this preferable design is adopted to analyze the alteration on its performance. The result indicates that, the retreating turbine impeller is the best for a high in-side heat transfer coefficient and the half coil jacket is the best for a maximum outside heat transfer coefficient. The performance investigation shows that this design is preferable for the optimum recommended flow velocity in the jacket of v = 2.3 m/s, as the outside heat transfer coefficient would increase by 31.47%. Finally, the new approach which is released by Vinnolit Uhde Company is applied and its result show that the heat duty would increase by 32% due to the installation of an inner cooler inside the reactor wall, which represents a significant stride for a high performance polymer reactor.

Estimation on structural availability of slender beam's yield strength, using structural failure model based on the Poisson approximation

This paper presents a new approach to the structural availability quantification of a slender beam element affected by external random loads with a special focus on yield strength. The proposed method introduces the concept of structural availability, which is intrinsically identical to the concept of operational availability in system reliability engineering. Structural availability is formulated with structural failure and repair models. The failure model is determined based on failure probability and the Poisson approximation. In applying the structural availability method to design, it is possible to quantitatively measure features related to the operation and maintenance of structures and to identify cost-effective design options. To understand feasibility levels of structural availability, two cases based on actual design data are examined using the proposed method. The case study results illustrate not only processes of quantifying the structural availability of a beam element but also the cost-effectiveness evaluations on specific design options.

三维姿态角高精度测量装置

A high accuracy measuring device and corresponding measuring method for three;dimensional attitude angles (yaw, pitch and roll) were designed based on an autocollimator and a coordinate rotary transfer matrix. The working principle and structural composition were introduced. A three;dimensional attitude angle measuring model was established and the theory algorithm by coordinate rotation matrix was derived based on the principle of autocollimation angle measurement. Then, the optical system was designed according to the demand of the measurement system. A single Field Programming Gate Array (FPGA) was used to implement double CMOS image sensor imaging, spot identifying, subdivision positioning, three;dimensional attitude angle calculation and rapid communication with a USB. To ensure the unity of the actual equipment parameter and design data, a high precision calibration method was researched for the three;dimensional attitude angle measuring device. Finally, three;dimensional attitude angles were tested to verify this measuring device, and the degrees and the factors affecting the angle measuring accuracy were analyzed as well. Calibration and experiment measurement results indicate that the measuring precisions of the yaw, pitch and roll angles for the measuring device are 2.2″, 2.5″ and 7.8″ respectively in view field of ±20'. It shows that the three;dimensional attitude angle measuring device has higher precision, simpler structure as well as stronger stabilization, and can be widely applied to engineering practices. © 2016, Science Press. All right reserved.

Earthquake performance assessment and retrofit investigations of two suspension bridges in Istanbul

This paper presents the results from earthquake performance assessment and retrofit investigations for Fatih Sultan Mehmet and Bosporus suspension bridges, with main span lengths of 1090 and 1074 m in Istanbul. In the first part of the study, sophisticated three-dimensional finite element model of two suspension bridges were developed and the results of the free vibration analysis were presented. The models contain detailed structural components of the bridges and geometric non-linearity with cable sagging and stress stiffening, cumber of the deck and set-back of the towers. These components affect the natural frequencies and the corresponding mode shapes of the bridges. In the second part of the study, the seismic performance evaluation of two suspension bridges was undertaken. For performance assessments, non-linear 3-D finite-element time history analysis of with multi-support scenario earthquake excitation was used. Displacements and stresses at critical points of the bridges were investigated. Their earthquake performance under the action of scenario earthquake (site-specific ground motion that would result from the Mw=7.5 scenario earthquake on the Main Marmara Fault) were estimated and comparison with actual design data were also presented. Although both suspension bridges were originally designed for much lower earthquake loads they exhibited satisfactory performance. Finally, suggestions for retrofit need were made and retrofit design with hysteretic dampers for the Bosporus suspension bridge was calculated.

Transistor Sizing of LCD Driver Circuit for Technology Migration

Design automation of LCD driver circuits is not sophisticatedly established. Display fineness of an LCD panel depends on a performance metric, ratio of pixel voltage to video voltage (RPV). However, there are several other important metrics, such as area, and the best circuit cannot be decided uniquely. This paper proposes a design automation technique for a LCD column driver to provide several circuit design results with different performance so that designers can select an appropriate design among them. The proposed technique is evaluated with an actual design data, and experimental results show that the proposed method successfully performs technology migration by transistor sizing. Also, the proposed technique is experimentally verified from points of solution quality and computational time.

DRAWING DATA REFINING SYSTEM ACCORDING TO PLANT PRODUCT LIFE CYCLE

Engineering data warehouse has been developed in order to integrate and exchange data through lifecycle of process plants. Based on a common information model, CAD data translators from 2D drawings and 3D models were built and their browsers have been also built. In order to adopt every task in the plant related work with its design data, such as process and instrumentation 2D drawings, a continuous refining system for drawing data has been built. With this system, a mechanism for keeping data consistency between actual project data and design data has been considered.

MODELING SUBSURFACE DRAINAGE FLOW OF A TILE-DRAINED SMALL WATERSHED USING DRAINMOD

The watershed-scale simulation model DRAINMOD was used to model the hydrology of a tile-drained Indianaagricultural watershed. The goal of the research is to study whether local measured soil data can be replaced by publishedSSURGO soil survey data, and the Indiana Drainage Guideline can replace actual system design data in simulating thehydrology of the watershed. Field-scale DRAINMOD model output was compared to gauged field data, and then applied tothe watershed-scale using a GIS-integrated DRAINMOD for simulating the hydrology of tile drained watersheds. A sensitivityanalysis was performed to determine the parameters that would most affect drainage flow at the watershed scale. Theparameters that were determined to be the most effective in changing the model output were drain depth, drain spacing, andsaturated hydraulic conductivity. Simulations show that DRAINMOD was able to simulate the hydrology of the gaugedwatershed with reasonable accuracy when tile drainage system design was based on the Indiana Drainage Guidelines (IDG).The use of published soil hydraulic properties, guidelines for drainage system design and the understanding of parametersthat are most effective in changing drainage flow enables the user to predict drainage flow at the watershed scale with alimited set of available input data.

Artificial Neural Network Based Designing System for Induction Motors

An artificial neural network (ANN) based designing method has been proposed for induction motors. Based on the real design data for various types of induction motors with different rating, three-layered cascaded artificial neural networks have been specified and trained to estimate the fundamental quantities and parameters, and also to give proper sizes of the target induction motor. Totally, thirty-four cage rotor type induction motors, which were designed by different engineers, have been selected for the training data. These induction motors have different ratings, different capacities, and different usage, i. e., driving units for pumps, compressors, and fans. The type of cooling method is totally enclosed the fan cooled type for all the selected induction motors. Through the numerical simulations based on the actual design data for different types of induction motors, the efficiency of the proposed designing system has been demonstrated.

ANN based designing and cost determination system for induction motor

An artificial neural network based computer-aided designing system together with the manufacturing cost estimation system for industrial induction motors is presented. The aim is to contribute to the understanding of the new system. Based on the actual design data for various types of induction motors, the cascaded artificial neural networks have been trained to calculate the output of the fundamental data and parameters. After the training, the dimensions and the basic parameters have been estimated quite accurately from the specification of the individual induction motor on the cascaded three artificial neural networks. The manufacturing cost of the individual motor has also been predicted precisely by using the neural network at the last stage of design. The proposed neural network based designing system including the cost estimation system is quite efficient in reducing the manpower of the designing process and also in enabling optimal design in a restricted time period without the knowledge of experts.

Geometric Modeling of Highways Using Global Positioning System Data and B -Spline Approximation

The proliferation and increased precision of global positioning system (GPS) devices enable the technology to be used in new and innovative applications. In the past few years, the Kansas Department of Transportation collected spatial data on a highway system using annual GPS surveys. This research deals with the problem of handling very large amounts of geographical data (latitude, longitude, elevation, and additional attributes) that are not entirely consistent. This paper describes the methodology for cleaning up this large amount of data, condensing it, and generating a B-spline approximation of the highway. This data mining effort results in two separate two-dimensional models of the highway, represented as B-spline curves. The highway approximation methodology is validated using a comparison between the B-spline approximation and the actual design data for the highway.

Prediction of hottest spot temperature (hst) in power and station transformers

The degradation of electrical insulation in transformers is more often due to thermal stress. In this paper, the authors attempted to work out a method of assessing the magnitude of temperature and the hottest region in the body of a large transformer with a reasonable degree of accuracy. A theoretical model has been developed based on the boundary value problem of heat conduction in transformer winding using finite integral transform techniques. The model requires, in addition to electrical parameters of the transformer, information on the actual design data. The authors believe that this model predicts HST with precision and also indicates a possibility of online data acquisition.

Application of Genetic Algorithm with Preprocessing to Cable Installation Design in Large-Scale Plant

This paper describes the application of genetic algorithm (GA) to a cable installation design in a large-scale plant. This application assumes that the design of plant equipment and cable trays has been completed. Here, to deal with the exceedingly large number of cable-route combinations in a large-scale plant, we propose a new preprocessing method using the Dijcstra method for constructing genes that significantly reduces the number of combinations and improves the search for the shortest route. Moreover, based on correlation analysis between evaluated values, we pay particular attention to cable grouping that skilled designers have come to emphasize in their design work, and propose a new method for installing cables that uses cable grouping as a genetic operator. This method achieves a level of optimization exceeding that of manual design and substantially reduces computational time. Comparing with actual design data from skilled designers, it was found that the above methods can produce an even more satisfactory solution in a practical period of time (within two hours) on a workstation.

地下鉄整備のライフサイクル環境負荷に関する研究

We conducted a life cycle assessment for the subway system in Fukuoka City. We estimated the direct and indirect energy requirements necessary for the construction of subway tunnels using the actual design and specification data such as the amount of basic materials, fuels and machines used for construction. We studied three different construction methods: cut and cover, mountain, and shield tunnelling. The estimated per length energy requirements of the tunnels constructed by these three methods are 4, 900 TOE/km, 6, 900TOE/km, and 10, 300TOE/km, respectively. These values are roughly proportional to the per length construction cost of the tunnels. The total energy required for construction is almost 14 times as large as that required annually for the operation and maintenance of trains and stations.

Improving Design and Fabrication of Bridges Using Knowledge Base

Because the cost of steel bridges in Japan is generally estimated using the price per unit weight, bridge designers and fabricators are required to decrease the steel weight of the bridge. This results in increasing the number of cross-section variations and the number of weld lines. However, because of the shortage of technicians and increase in labor cost, it is becoming necessary to consider the possibilities of simplifying and accelerating the fabrication process to get a more rational and a near optimal design. Knowledge-based systems, when combined with actual design data of available bridges, can support the decision-making process for improving both design and fabrication. This paper discusses the creation of a knowledge base that includes data on previously designed plate-girder bridges, and its application in considering the effects of simplifying the design on the cost of the bridge. First, the steps used in the creation and processing of the knowledge base are explained. Then, the knowledge base is used to investigate several design alternatives by selecting and redesigning some bridges. Several suggestions for a more rational design are given, based on previous design information.

Current-carrying capability for industrial underground cable installations

A method of extending the IEEE-ICEA calculations to a wide range of conditions encountered in connection with industrial installations is presented. The specific physical duct bank configurations and assumed parameter, which are the cause of limitations in the applicability of the IEEE-ICEA ampacity tables, are replaced by actual design data. Computerized application of the method affords efficient handling of a large number of cables in any practical physical configuration. The calculations are carried out for any combination of cable sizes, taking into account the actual load factor for each cable. The relative impact of various factors affecting the current rating is discussed. User experience with the method and sample calculations are included. >