Journal articles: 'Load-flow calculations'

1

Hartmann, M. J., and G. P. McCarthy. "Computerized DC (battery) load flow calculations." IEEE Industry Applications Magazine 2, no. 4 (1996): 53–56. http://dx.doi.org/10.1109/2943.503529.

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Mombauer, W., and K. H. Week. "Load modelling for harmonic flow calculations." European Transactions on Electrical Power 3, no. 6 (September 6, 2007): 453–60. http://dx.doi.org/10.1002/etep.4450030610.

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Shu, Tian, and Wang Li. "Power Flow Calculation in Distribution System Considering Different Load Model." Advanced Materials Research 722 (July 2013): 103–6. http://dx.doi.org/10.4028/www.scientific.net/amr.722.103.

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In traditional power flow calculation used constant power load model, it was completely unreasonable to assume that all load nodes in power system can be classified as PQ nodes.In that the result of constant power load model does not accurately reflect the distribution characteristics of network power flow. To put forward power flow calculation considering load models ,such as constant power load ,constant current load and constant resistance load, derives error equations of the node power, calculates element of Jacobian matrix. So, by using MATLAB simulation software ,the program for power flow are presented, which based on the method of different load models, taking 21-node system for example and makes comparative calculations. The research shows that power flow calculation considering different load models can get more reasonable solution.

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Seng, Chieng Kai, Tay Lea Tien, and Syafrudin Masri. "Load Flow Analysis Using Second-Order Load Flow Methods and its Variations." Applied Mechanics and Materials 785 (August 2015): 73–77. http://dx.doi.org/10.4028/www.scientific.net/amm.785.73.

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The load flow or power flow computer program is the basic tool for investigating the steady-state conditions of power system. This paper introduces improved algorithms based on the basic Second-order Load Flow method for a wide range of electrical bus system sizes. It is attractive for accurate or approximate off- and on-line calculations for routine and contingency purposes. Tests of 4 different variations based on the basic Second-order Load Flow method are run on 6 different standard bus systems and the results are discussed in this paper.

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Harifin, Hayatul, Novalio Daratha, and M. Khairul Amri Rosa. "Pengembangan Perangkat Lunak Untuk Analisis Aliran Beban Tiga Fasa Pada Jaringan Tegangan Rendah Dengan Metode Newton Berbasis Calculus Wirtinger." JURNAL AMPLIFIER : JURNAL ILMIAH BIDANG TEKNIK ELEKTRO DAN KOMPUTER 10, no. 2 (November 30, 2020): 20–27. http://dx.doi.org/10.33369/jamplifier.v10i2.15318.

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AbstractLoad flow analysis is a study to plan and determine the amount of power in an electric power system. During its development, industry requires a large amount of electric power and uses electrical equipment as a means of production. The benefits of an electric load flow analysis are to find out the amount of power in the electric power system whether it still meets predetermined limits, and to find out the amount of voltage at each point, and to obtain initial conditions for the new system planning. Load flow analysis begins calculating the active power and reactive power at each node (bus) installed, loading on the channel or conductor, the load flow calculation will be assisted using the Julia program. From the results of calculations using the Julia program, the voltage at each point with the smallest stress is obtained, namely the 10th point of 209.89 - j10.34V for phase A, -107.39 - j186.87V for phase B, -108.12 + j178,51V for phase CKey Words: Drop Voltage, Julia, Load Flow

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Zheng, Wei, Fang Yang, and Zheng Dao Liu. "Research on Fast Decoupled Load Flow Method of Power System." Applied Mechanics and Materials 740 (March 2015): 438–41. http://dx.doi.org/10.4028/www.scientific.net/amm.740.438.

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The power flow calculation is study the steady-state operation of the power system as basic electrical calculations. It is given the power system network topology, device parameters and determines system health boundary conditions, draw a detailed operating status of the power system through numerical simulation methods, such as voltage amplitude and phase angle on the bus system the power distribution and the power loss. Flow calculation is the power system operation, planning and safety, reliability analysis, is fundamental to the system voltage regulation, network reconfiguration and reactive power optimization must call the function, so the trend has very important significance to calculate the power system.

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Seng, Chieng Kai, Tay Lea Tien, Janardan Nanda, and Syafrudin Masri. "Load Flow Analysis Using Improved Newton-Raphson Method." Applied Mechanics and Materials 793 (September 2015): 494–99. http://dx.doi.org/10.4028/www.scientific.net/amm.793.494.

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This paper describes a simple, reliable and swift load-flow solution method with a wide range of practical application. It is attractive for accurate or approximate off-and on-line calculations for routine and contingency purposes. It is applicable for networks of any size and can be executed effectively on computers. The method is a development on conventional load flow principle and its precise algorithm form has been determined to bring improvement to the conventional techniques. This paper presents a comparative study of the new constant Jacobian matrix load flow method built based on several conventional NR load flow methods. Assumptions are made so as to make the matrix constant, thus eliminating the need of calculating the matrix in every iteration. The proposed method exhibits better computation speed.

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Xiao, P., D. C. Yu, and W. Yan. "A Unified Three-Phase Transformer Model for Distribution Load Flow Calculations." IEEE Transactions on Power Systems 21, no. 1 (February 2006): 153–59. http://dx.doi.org/10.1109/tpwrs.2005.857847.

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Meisel, J. "System incremental cost calculations using the participation factor load-flow formulation." IEEE Transactions on Power Systems 8, no. 1 (1993): 357–63. http://dx.doi.org/10.1109/59.221220.

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Böckl, Benjamin, Matthias Greiml, Lukas Leitner, Patrick Pichler, Lukas Kriechbaum, and Thomas Kienberger. "HyFlow—A Hybrid Load Flow-Modelling Framework to Evaluate the Effects of Energy Storage and Sector Coupling on the Electrical Load Flows." Energies 12, no. 5 (March 12, 2019): 956. http://dx.doi.org/10.3390/en12050956.

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HyFlow is a grid-based multi-energy system (MES) modelling framework. It aims tomodel the status quo of current energy systems, future scenarios with a high share of fluctuatingenergy sources or additional consumers like electric vehicles, and to compare solution strategies ifcertain parts of the infrastructure are congested. In order to evaluate the congestion limits and thefeasibility and suitability of solution strategies (e.g., energy storage, sector coupling technologies,demand response (DR)), load flow calculations of all three main grid-bound energy carriers areimplemented in one single modelling framework. In addition to the implemented load flow models,it allows the interaction of these grids with the use of hybrid elements. This measure enables aproper assessment of future scenarios, not only for the infrastructure of one energy carrier, but forthe overall energy system. The calculation workflow of HyFlow, including the implemented loadflow calculations, as well as the implementation of the flexibility options, is described in detail inthe methodology section. To demonstrate the wide range of applicability of HyFlow with differentspatial ranges, two case studies referring to current research problems are presented: a city and aregion surrounding the mentioned city. The calculations for the mentioned case studies areperformed for three levels. A “status quo” level, a “high-stress” level with added fluctuatingenergy sources and consumers, and an “improvement” level, where flexibility options areintroduced to the system. The effect of the flexibility options on future energy grids is, therefore,analyzed and evaluated. A wide variety of evaluation criteria can be selected. For example, themaximum load of certain power lines, the self-sufficiency of the overall system, the total transportlosses or the total energy consumption.

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Liu, Jianbin, Haibo Xie, Liang Hu, Huayong Yang, and Xin Fu. "Flow force regulation of the main poppet in a large flow load control valve." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 231, no. 8 (June 9, 2017): 706–20. http://dx.doi.org/10.1177/0957650917714370.

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This paper presents the regulation methods of flow forces acting on the main poppet in a large flow load control valve. The negative flow forces working on the originally designed main poppet, which is as high as 10% of the control force, act as a big disturbance to the main poppet position control, resulting in poor lowering speed control performance of the load control valve or even instability of the main poppet. Firstly, by introducing a damping tail structure to the main poppet, the direction of the flow forces can be regulated to positive and best stability of the main poppet can be achieved with the calculated best parameter combination. Secondly, by introducing a damping tail with holes to the main poppet, the positive flow forces of all main poppet positions can be reduced to minimum, which results in minimum disturbance for the control of main poppet. Computational fluid dynamics calculations were conducted to analyze how the damping tail parameters affect the flow forces and obtain the best parameter combinations. A test rig was set up to validate the effect of above methods. Good agreement of the computational fluid dynamics calculations and experiment results indicates that the proposed methods can provide guidance for the flow force regulation of other valve poppets.

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Kucaba-Piętal, A. "Squeeze flow modeling with the use of micropolar fluid theory." Bulletin of the Polish Academy of Sciences Technical Sciences 65, no. 6 (December 1, 2017): 927–33. http://dx.doi.org/10.1515/bpasts-2017-0100.

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AbstractThe aim of this paper is to study the applicability of micropolar fluid theory to modeling and to calculating tribological squeeze flow characteristics depending on the geometrical dimension of the flow field. Based on analytical solutions in the lubrication regime of squeeze flow between parallel plates, calculations of the load capacity and time required to squeeze the film are performed and compared – as a function of the distance between the plates – for both fluid models: the micropolar model and the Newtonian model. In particular, maximum distance between the plates for which the micropolar effects of the fluid become significant will be established. Values of rheological constants of the fluids, both those experimentally determined and predicted by means of using equilibrium molecular dynamics, have been used in the calculations. The same analysis was performed as a function of dimensionless microstructural parameters.

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Kauppila, Pirkko, and Jari Koskiaho. "Evaluation of Annual Loads of Nutrients and Suspended Solids in Baltic Rivers." Hydrology Research 34, no. 3 (June 1, 2003): 203–20. http://dx.doi.org/10.2166/nh.2003.0004.

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Estimation of pollutant fluxes through river systems calls for accurate and precise load estimation. However, considerable uncertainty is associated with these estimates due to diffuse loading, which sets high requirements not only on sampling frequencies but also on calculation methods. The aim was to examine the variation in load calculations and the reliability of the load estimates of total phosphorus, total nitrogen and suspended solids in 24 Baltic rivers varying in size and land-use characteristics. Reliability of the load estimates was tested by simulation experiments in the river Paimionjoki using a Monte Carlo procedure. The estimates calculated by the most reliable method were compared to the loads estimated by five other methods. The general reliability (RMSE) for P and SS was best by the correlation method and for N by the periodic method. Load calculations varied greatly depending both on the characteristics of the rivers and the calculation method. The flow-stratified method overestimated the P and SS loads by about 20% in large low-lake rivers. In small low-lake rivers, the overestimation was 10% and over 14% for P and SS, respectively. By contrast, the averaging method underestimated P and SS loads by 10% and 21% in small agricultural low-lake rivers. All the methods produced rather similar results for N in each of the river types.

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14

Amano, M., A. I. Zecevic, and D. D. Siljak. "An improved block-parallel Newton method via epsilon decompositions for load-flow calculations." IEEE Transactions on Power Systems 11, no. 3 (1996): 1519–27. http://dx.doi.org/10.1109/59.535693.

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Gu, Hua, and Gen Hua Yan. "Research on the Effect of Fluid-Structure Interaction on Dynamic Response of Gate Structure." Advanced Materials Research 199-200 (February 2011): 811–18. http://dx.doi.org/10.4028/www.scientific.net/amr.199-200.811.

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This essay reveals that on the basis of fluid-structure interaction having appreciable impact on auto-vibration of gate structure, analysis and calculation on dynamic response characteristics of gate structural fluid-structure interaction have been conducted. The results indicate that under the same dynamic load the structural dynamic response value with fluid-structure interaction effect considered is remarkably larger than vibration response with fluid-structure interaction effect considering. The calculating results indicate that the largest response increase of typical parts of gate structure is from 50% to 60%. Therefore, as to making calculations on structural dynamic response with fluid-structure interaction effect, the impact flow field exerting on structural response should be taken into consideration.

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Grądziel, Sławomir, and Karol Majewski. "Simulation of heat transfer in combustion chamber waterwall tubes of supercritical steam boilers." Chemical and Process Engineering 37, no. 2 (June 1, 2016): 199–213. http://dx.doi.org/10.1515/cpe-2016-0017.

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Abstract The paper presents the results of numerical computations performed for the furnace chamber waterwalls of a supercritical boiler with a steam output of 2400 × 103 kg/h. A model of distributed parameters is proposed for the waterwall operation simulation. It is based on the solution of equations describing the mass, momentum and energy conservation laws. The aim of the calculations was to determine the distribution of enthalpy, mass flow and fluid pressure in tubes. The balance equations can be brought to a form where on the left-hand side space derivatives, and on the right-hand side – time derivatives are obtained. The time derivatives on the right-hand side were replaced with backward difference quotients. This system of ordinary differential equations was solved using the Runge-Kutta method. The calculation also takes account of the variable thermal load of the chamber along its height. This thermal load distribution is known from the calculations of the heat exchange in the combustion chamber. The calculations were carried out with the zone method.

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Gong, Dong Jun, Yao Zhang, Xing Ru Li, Li De Fang, Zi Hui Wei, and Ning Zhao. "Study on the Resistance Characteristics of Heat Metering System Based on Electric Valve." Applied Mechanics and Materials 492 (January 2014): 507–10. http://dx.doi.org/10.4028/www.scientific.net/amm.492.507.

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Through theoretical calculations and derivation, the paper obtained the relationship between resistance coefficient and pressure difference, as well as flow rate. For the series pipeline, the flow in the series pipeline is the same, as a result, all the resistance in the series pipeline is the total resistance. For the parallel pipeline, the pressure difference is same, and the all the flow in parallel pipeline is the total flow. According to the real example, the paper identified the inlet pressure difference of the indoor system, the most unfavorable ring and the ratio frictional resistance. Based on the room heat load calculation, the paper determined the most unfavorable loop diameter of each pipe section. By calculating the resistance coefficients of the electric valve at opening, the resistance coefficients of the electric valve at closing were obtained. In the experiment system, the resistance coefficient average value when the electric valve is off was 101831.65, which is basically in line with the calculable value 10719.6, indicating that the existing parameters are much more reasonable.

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Bloor, M. I. G., and M. J. Wilson. "An approximate analytic solution method for the biharmonic problem." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 462, no. 2068 (January 17, 2006): 1107–21. http://dx.doi.org/10.1098/rspa.2005.1603.

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A method is presented for the solution of the biharmonic equation through the use of a combination of polynomial and eigenfunction solutions. Results are presented comparing the method with an exact solution. Excellent agreement is obtained for economical solution representations. Calculations, and comparison with established results, of the displacement of an elastic plate under a uniform applied load are presented. Further, results are presented of the calculation of zero Reynolds number flow in a driven cavity.

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Liu, Chang Liang, and Ya Long Gao. "Thermal Power Plant Electrical Network Flow Calculations Based on AnySimu Platform." Applied Mechanics and Materials 241-244 (December 2012): 1234–39. http://dx.doi.org/10.4028/www.scientific.net/amm.241-244.1234.

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In this paper, the Guodian Zhishen development of DCS as a platform, set up a thermal power plant 1000MW unit auxiliary power electrical system diagram AnySimu platform for simulation support system, and electrical network designed according to the principle of power flow calculation algorithm to calculate theeach node voltage, phase, and thus the load operator. After the simulation, verify the validity of the algorithm.

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Ariyo, Funso K. "Electrical Network Reduction for Load Flow and Short-Circuit Calculations Using Power Factory Software." American Journal of Electrical Power and Energy Systems 2, no. 1 (2013): 1. http://dx.doi.org/10.11648/j.epes.20130201.11.

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Guerra, Gerardo, and Juan A. Martinez-Velasco. "Evaluation of MATPOWER and OpenDSS load flow calculations in power systems using parallel computing." Journal of Engineering 2017, no. 6 (June 1, 2017): 195–204. http://dx.doi.org/10.1049/joe.2017.0023.

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Li, Quan, Xin Wang, and Shuaiang Rong. "Probabilistic Load Flow Method Based on Modified Latin Hypercube-Important Sampling." Energies 11, no. 11 (November 15, 2018): 3171. http://dx.doi.org/10.3390/en11113171.

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The growing amount of distributed generation has brought great uncertainty to power grids. Traditional probabilistic load flow (PLF) algorithms, such as the Monte-Carlo method (MCM), can no longer meet the needs of efficiency and accuracy in large-scale power grids. Latin Hypercube Sampling (LHS) develops a sampling efficiency and solves the correlation problem of distributed generation (DG) access nodes for accuracy analyses. In this paper, a modified Latin Hypercube-Important Sampling method is proposed for higher efficiency and precision by using the importance sampling method before LHS and the Cholesky decomposition method in correlation calculations. The simulation results are presented using a modified IEEE 30-bus system and are compared with traditional MCM and LHS.

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Lausová, Lenka, Vladimíra Michalcová, and Ivan Kološ. "Numerical modeling of flow around a heated cylinder with a rough surface." MATEC Web of Conferences 313 (2020): 00046. http://dx.doi.org/10.1051/matecconf/202031300046.

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The article deals with the numerical solution of the load of a heated chimney from wind effects. The paper examines flow around a heated cylinder with the rough surface in high Reynolds number regime. The results of drag coefficient, pressure coefficient and other related flow properties are compared with the calculations of the flow around the unheated cylinder.

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Naumov, Vladimir. "Effect of Liquid Food Viscosity on the Load Characteristics of Single-Screw Pumps." Food Processing: Techniques and Technology 51, no. 2 (June 15, 2021): 290–300. http://dx.doi.org/10.21603/2074-9414-2021-2-290-300.

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Introduction. Hydraulic calculations of flow parts play an important role in the improvement of modern technological lines. Such calculations do not include the characteristics of pumping units. Single-screw pumps (SSP) pump high-viscosity liquids in modern food production. The research objective was to develop a new engineering method for assessing the effect of the viscosity of non-Newtonian fluids on the load characteristics of SSP in food production. Study objects and methods. The research featured SSP with a hopper and an auger, designed for pumping high-viscosity liquids. The initial data were taken from officially published test results of Atlas W SSP and the study of the rheological properties of confectionery jelly masses. The research involved authentic methods for calculating the load characteristics of SSP based on the effect of the viscosity of pumped liquid. According to the first approximation, the change in the dimensionless load characteristics was similar in different SSP with an increase in the viscosity of the pumped liquid. The dependence of the viscosity on the rotation speed was determined by the Bingham formula. Results and discussion. The test results of the Atlas W SSP confirmed the need to take into account the minimum rotation speed at which liquid pumping begins in the calculations. The specified frequency was directly proportional to the differential pressure for this series. The study revealed approximate load characteristics of the SSP during jelly pumping. While pumping viscous foods, SSP demonstrated poorer performance and bigger power consumption than during pumping water. The supply decreased and the power increased as the temperature went down and the pectin content in confectionery jelly masses rose. Conclusion. The dependences of the flow rate and power consumed on the rotation speed published by the manufacturers of SSP were obtained during tests on water. The present research resulted in a new method to assess the load characteristics of the SSP when pumping high-viscosity liquids in food production. The obtained regression dependences need further refinement and experimental verification. The method can be used to design new technological pipelines.

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WINARNO, SUKO. "ANALISA PERHITUNGAN BEBAN PENDINGINAN RUANG PERANGKAT INTERNET DI PT. X - SITE KEDATON." Jurnal Teknik Mesin 8, no. 3 (April 27, 2020): 1. http://dx.doi.org/10.22441/jtm.v8i3.4581.

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Abstract -- The cooling process in the internet device room has an important function in maintaining room temperature so that the equipments in the room stay at the desired temperature. With optimal cooling, the equipments in the room are expected to function optimally. The author analyzes the condition of the internet device room with the research method used is by taking field data and analyzing the calculation of the data using formula formulas obtained from the literature. After calculating the data , then the average value of the Thermal load of the room is 3260 Watt, the average of room temperature is 22.95 0 C, the average enthalpy value in the room is 42.72 kJ / kg.a. Then the enthalpy value of the evaporator is 35.86 kJ / kg.a. Then the average value of the mass flow rate coming out of the evaporator is 0.48 Kg / s. From these calculations it can be concluded that the highest room temperature is at 11.00 AM, the average room thermal load value is at 1.20 PM, then the highest enthalpy value of the room occurs at 11.00 AM, then the highest value of enthalpy of the evaporator occurs at 11.00 AM, and the highest average value of mass flow rate occurs at 1.20 PM.

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Yaseen, Ahmed Y., and Afaneen A. Abbood. "Study of Power System Load Flow Using FPGA and LabVIEW." Engineering and Technology Journal 38, no. 5A (May 25, 2020): 690–97. http://dx.doi.org/10.30684/etj.v38i5a.346.

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The capability to rapidly execute the power flow (PF) calculations permit engineers in assured with stay bigger assured within the dependability, protection, and economical operation of their system within the case of planned or unplanned instrumentality failures. The purpose of this work is to investigate the use of FPGA characteristics to speed up power flow computing time for the on-line monitoring system of a power system. The work comprises which is the development of the Power flow program using the Fast-decoupled method based on FPGA (Field Programmable Gate Array), and LABVIEW (graphical programming environment). The program delivered very satisfactory results to solve a 30-bus test system. These findings suggest that in general that differences between the proposed work and the conventional fast decoupled method are satisfactory. As for the execution time, because the FPGA uses parallel solutions, the performance of the proposed method is faster. Also, the engagement of the FPGA and the LabVIEW program presented an effective monitoring system for observing the power system.

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Yang, Jia, Hai Bao, Ling Wang, and Gang Liu. "An on Line Method of the Steady-State Data Acquisition." Applied Mechanics and Materials 385-386 (August 2013): 668–74. http://dx.doi.org/10.4028/www.scientific.net/amm.385-386.668.

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Steady-state power flow calculation belongs to power system steady-state analysis, and the data used in calculation should be steady-state data. However, the existing SCADA system hasnt distinguished the transient data from the steady-state data. The real-time measured data reflect the dynamic electric power system. It is the right reason for not all of the real-time measured power can be used for power flow calculation. In another word, it causes the matching problem between measured data and power flow calculations. Based on the current situation of information collection system, the characteristics of the measured data had been analyzed in this paper. And an effective acquisition method for steady-state measured data is proposed on the theoretical basis of the law of large numbers. It uses the average value of the measured data that in the same load state to approximate the steady-state true value in one period. And the steady-state data can be used in power flow calculation. The simulation results show that the method proposed in this paper ensures the accuracy and reliability of power flow calculation.

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Butts, C. L. "Correcting Current Moisture Calculations for Purchasing High Moisture Farmers Stock Peanuts1." Peanut Science 25, no. 2 (July 1, 1998): 114–19. http://dx.doi.org/10.3146/i0095-3679-25-2-11.

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Abstract The U.S. peanut industry may eliminate the 10% moisture content threshold for purchasing peanuts to facilitate implementing continuous flow drying systems and to increase the efficiency of the postharvest processing system. Equations based on the theoretical definition of wet basis moisture content were proposed to determine the weight of various components in a load of farmers stock peanuts. These equations more accurately describe and account for the distribution of moisture within a load of peanuts. Accurate descriptions of the amount of loose shelled kernels, foreign material, and in-shell peanuts would enable improved tracking of losses during storage. Compared to the current price structure, the proposed equations predict reduced payments to growers no more than $30 per 5-mt load of peanuts. The maximum reduction of $30 occurred if peanuts were delivered and marketed at 30% w.b. moisture content. A reduction of approximately $8.50 would occur for a 5-mt load delivered at 15% moisture content. The cumulative economic impact warrants adjustment of the peanut support price schedule if accurate accounting of moisture is implemented.

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Zhang, Chuan Cheng, Cui Hui Yan, Sai Dai, Dan Xu, Yi Zhu, and Wei Dong. "Improved Probabilistic Load Flow Method to Consider Random Generator Outages." Advanced Materials Research 962-965 (June 2014): 2783–88. http://dx.doi.org/10.4028/www.scientific.net/amr.962-965.2783.

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In conventional cumulant method of probabilistic load flow (PLF), random generator outages are usually simulated by discrete distributions of nodal power injections, but that will lead to significant error in AC load flow model. An improved PLF method base on AC model is proposed in this paper, which considers random generator outages and loads uncertainties. Cumulant and Gram-Charlier series expansion were applied to deal with the random variations of loads, instead of convolution calculations. According to the characteristics and focused aspects of power grid, certain generators were selected to form event group of generator outages and each event was analysed by exact load flow.Then total probability theorem was introduced to obtain the probabilistic distributions of node voltages and line flows that considered random factors of loads and generators.The case study of IEEE 39-bus system shows that the random generator outages remarkably affect the probabilistic distributions of state variables. The proposed method can avoid the error caused by generator outages in conventional cumulant method. Furthermore, the result of proposed method is consistent with that of Monte Carlo simulation, while computation speed is much faster.

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Bicbulatov, Arnold Sh, Asia А. Usmanova, and Arthur I. Nurmukhametov. "Сonstruction and study of the load characteristics of the heat exchanger." Butlerov Communications 58, no. 4 (April 30, 2019): 140–45. http://dx.doi.org/10.37952/roi-jbc-01/19-58-4-140.

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The existing practice of designing heat exchangers is based on the application of an engineering method of calculation, the so-called graphical method. Therefore, the design principle of the method consists in solving a system of nonlinear equations describing the heat exchange between coolants composed of various organic substances toluene, benzene, using the method of successive approximations, and the number of approximations can be very large. Randomly given by a number of unknown quantities, namely the temperatures of the pipe walls and some structural dimensions of the apparatus, which are further specified when performing the calculations, are specified. A graph is plotted for the specific heat fluxes for both fluids from the assumed temperatures of the pipe wall, and the lines, the so-called load characteristics of the heat exchanger, are drawn through the points obtained. The analysis of the conditions of application of the load characteristics of the heat exchanger when calculating the surface of the apparatus for the three main types of heat exchange, implemented in heat exchangers: boilers, condensers, cooler-heaters in which heat transfer occurs between various organic liquids under various conditions of their work. It is shown that the load characteristics of heat exchangers are non-linear depending on the specific heat flux on the pipe wall temperature, and the curvature of the line deviations from the straight line depends on the type of heat exchange and the flow of coolants, the curvature of the lines is close to the straight line dependence in the laminar mode, significantly different from the straight line in the transition mode and turbulent regimes and is very different from the straight line dependence on heat exchange with a change in the state of aggregation of both fluids. A direct calculation of the surface of the apparatus has been proposed, a technique has been developed for determining the temperature of the pipe wall, selections of initial conditions for performing calculations, step-by-step changes in the magnitudes of the driving forces are recommended when performing approximations, which reduces the time spent on the calculation. The paper also analyzes the choice of changes in the magnitudes of the driving force of the heat transfer process for the number of approximations, shows the intervals of variation of this quantity at which the calculation error decreases. Direct determination of the surface of the device significantly increases the accuracy of the calculation of the surface.

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PIEKARSKI, Wiesław, and Andrzej KURANC. "Exhaust emissions and fuel consumption in a chassis dynamometer load test in the aspect of modification of an engine controlling system." Combustion Engines 171, no. 4 (November 1, 2017): 11–16. http://dx.doi.org/10.19206/ce-2017-402.

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The article presents calculations of exhaust emissions and fuel consumption under test conditions on a chassis dynamometer test bench. The study describes the realization of the tests and the methodology of the calculation of the exhaust gas flow and the estimation of the fuel consumption based on exhaust emissions. The presented research results and their analysis describe the emission scale of selected gaseous fumes components during full engine load and the fuel consumption associated with such tests. Similar emissions occur during a rapid acceleration of a vehicle in road conditions.

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Zhang, Tairui, Jianzhang Guo, and Weiqiang Wang. "A strain-pattern-based spherical indentation method for simultaneous uniaxial tensile residual stress and flow property determination." Journal of Strain Analysis for Engineering Design 56, no. 1 (June 3, 2020): 50–64. http://dx.doi.org/10.1177/0309324720921305.

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In this study, a strain-pattern-based method was proposed to simultaneously determine the uniaxial tensile residual stress and flow property from a single-cycle spherical indentation test. The variation of the plastic zone radius (at the specimen surface) with uniaxial tensile residual stress was analytically investigated by the expanding cavity model. The analysis proved that the circular plastic boundary will be elliptical under the action of uniaxial residual stress (with a shrunken plastic zone radius along the loading direction and an extended plastic zone radius vertical to the loading direction), and this difference can be used to calibrate the magnitude of the residual stress. The analytical result was verified and modified through finite element calculations, after which a set of regression functions for Holloman hardening metals was established for load compensation, proportional limit correction, and hardening exponent calculation. The effectiveness of the method was verified through finite element calculations of spherical indentation tests on 16 Holloman hardening and 6 metals used in engineering applications at different residual stress levels. The verification proved that maximum errors for strength and residual stress calculations are about 10% and 15%, respectively, and the potential of the new proposed method was validated.

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Cardenas, M., J. Gailani, CK Zeigler, and W. Lick. "Sediment transport in the lower Saginaw River." Marine and Freshwater Research 46, no. 1 (1995): 337. http://dx.doi.org/10.1071/mf9950337.

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A study of the resuspension, deposition and transport of sediments and the resulting changes in bathymetry in the lower part of the Saginaw River in Michigan has been made. The numerical model used in this study consists of a two-dimensional, vertically integrated, time-dependent hydrodynamic and transport model coupled with a three-dimensional, time-dependent model of the dynamics of the sediment bed and its properties. Transport of sediment as suspended load and bed load was included in the analysis. In the numerical calculations, curvilinear coordinates were used. For verification of the model, results of numerical calculations of changes in the thickness of the sediment bed due to time-varying flow events were compared with bathyrnetric measurements taken at nine transects on the river on 28 August 1991 and 13 May 1992. From the transect measurements, from measurements of flow rates and sediment concentrations, and from the numerical modelling, a reasonably accurate description of the sediment transport and the resulting bathymetric changes has been made. The calculations and observations show that resuspension/deposition, bed load, and slumping are significant factors in changing the bathymetry. It is also shown that the largest flows are responsible for most of the sediment erosion and deposition and must therefore be understood and considered in detail. An approximate procedure for making long-term (1 to 25 year) calculations is presented and discussed. This procedure greatly reduces the required computer time but still maintains the required accuracy for the prediction of sediment and contaminant transport and fate.

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Gasiūnas, Valerijus, and Jelena Lysovienė. "Nutrient retention efficiency of small regulated streams during the season of low-flow regime in Central Lithuanian lowland." Hydrology Research 45, no. 3 (August 23, 2013): 357–67. http://dx.doi.org/10.2166/nh.2013.005.

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Small streams are polluted with nutrients when crude or partially treated wastewater flows from settlements. The aim of the study was to determine the efficiency of small streams to self-purify themselves of nutrients during the season of low-flow regime. The study was carried out in five regulated streams with catchments of up to 30 km2 in the Central Lithuanian lowland. The retention of nitrogen (N) and phosphorus (P) compounds was studied up to 5.2 km downstream from the settlements. Owing to the pollution load from settlements, the concentrations of total N increased from 2.0–3.0 above the settlements to 6.75 ± 2.07 mg L−1 below; the concentrations of total P increased from 0.03–0.07 to 0.56 ± 0.30 mg L−1, with the stream's ecological state deteriorating to ‘poor’ and ‘bad’. For the calculation of total N retention, with respect to the pollution load and the distance from the settlement, an empirical equation was derived. Calculations show that with a pollution load of 2.0 g N m−3 at 5.0 km distance, around 90% of total N can be retained. However, when the load is threefold greater, at the same distance only 65% of total N is retained. As a result of self-purification processes only about 50% of total P may be retained.

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Kuranc, Andrzej, Tomasz Słowik, Paweł Krzaczek, and Grzegorz Maj. "Emission of Fumes of Ursus MF235 under Conditions of Load with The Use of a Movable Dynamometric Stand." Agricultural Engineering 20, no. 4 (December 1, 2016): 101–12. http://dx.doi.org/10.1515/agriceng-2016-0068.

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Abstract The article presents calculations of unit fumes emission made based on the measurements of the fumes composition during a load test. The test was carried out with the use of a movable dynamometric stand adjusted for testing agricultural tractors by power take-off shaft. Calculations of unit emission were made based on the assumed flow of air sucked by an engine and the measured composition of fumes emitted during the load test. Results of tests and analyses supply information on the mass of particle matter and the selected gas elements emitted by an engine working under the load which was related to simultaneous determination of the exploitation characteristic of an engine. The presented methodology may be helpful at evaluation of impact of farm tractors on the environment within the hazardous fume components emitted by them.

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BIJLARD, M. J., R. V. A. OLIEMANS, L. M. PORTELA, and G. OOMS. "Direct numerical simulation analysis of local flow topology in a particle-laden turbulent channel flow." Journal of Fluid Mechanics 653 (June 2, 2010): 35–56. http://dx.doi.org/10.1017/s0022112010000169.

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The results of point-particle Eulerian–Lagrangian direct numerical simulation (DNS) calculations of dilute particle-laden turbulent channel flow are used to study the effect of the particles on the local flow topology. It is found that in the viscous sublayer, the flow becomes increasingly more two-dimensional as the two-way coupling effect (due to interaction between particles and fluid flow) increases with increasing particle load. Beyond the viscous sublayer the modifications in flow topology are not strongly related to the preferential concentration of particles in the flow field, which is in contrast to previous channel flow simulations. The effect of particles on the turbulent flow beyond the viscous sublayer is mostly a result of the overall changing near-wall dynamics of the fluid flow.

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Zima, Wiesław, Sławomir Grądziel, and Artur Cebula. "Modelling of heat and flow phenomena occuring in waterwall tubes of boilers for supercritical steam parameters." Archives of Thermodynamics 31, no. 3 (September 1, 2010): 19–36. http://dx.doi.org/10.2478/v10173-010-0012-y.

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Modelling of heat and flow phenomena occuring in waterwall tubes of boilers for supercritical steam parametersIn this paper a mathematical model enabling the analysis of the heat-flow phenomena occurring in the waterwalls of the combustion chambers of the boilers for supercritical parameters is proposed. It is a one-dimensional model with distributed parameters based on the solution of equations describing the conservation laws of mass, momentum, and energy. The purpose of the numerical calculations is to determine the distributions of the fluid enthalpy and the temperature of the waterwall pipes. This temperature should not exceed the calculation temperature for particular category of steel. The derived differential equations are solved using two methods: with the use of the implicit difference scheme, in which the mesh with regular nodes was applied, and using the Runge-Kutta method. The temperature distribution of the waterwall pipes is determined using the CFD. All thermophysical properties of the fluid and waterwall pipes are computed in real-time. The time-spatial heat transfer coefficient distribution is also computed in the on-line mode. The heat calculations for the combustion chamber are carried out with the use of the zone method, thus the thermal load distribution of the waterwalls is known. The time needed for the computations is of great importance when taking into consideration calculations carried out in the on-line mode. A correctly solved one-dimensional model ensures the appropriately short computational time.

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Malyavina, Elena, and Alexander Lomakin. "Calculating the load on the room cooling ceiling panel at convective heat gains." E3S Web of Conferences 164 (2020): 02006. http://dx.doi.org/10.1051/e3sconf/202016402006.

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A well-known statement of the theory of thermal stability asserts that when a harmonically time-changing convective heat flux enters a room, it can only be assimilated by a radiant cooling system if the assimilating flow exceeds the perturbing convective flow in magnitude. However, in engineering practice, there are no purely radiant systems. Therefore, the article has considered a ceiling cooling panel as a room cooling system, the heat flow from which is of a radiant-convective nature. The convective heat access to the room is constant during the working hours from 9 a.m. to 6 p.m. The task of determining the load on the cooling system has been performed by calculations.. Herewith, the rooms of different internal thermal stability have been considered. According to the calculation results, it has been found that, since the amount of the heat gains remains constant for a long period of time, the process of the room cooling comes almost to a stationary state and does not depend on the room thermal stability with assimilated heat gains, the value of which in different options varied from 100 W to 1000 W. It has been found, that when the temperature difference between the panel surface and the surrounding surfaces increases, the proportion of the convective assimilating flow becomes bigger.

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Srihanto and Moch Sugiri. "PERENCANAAN SISTEM PENDINGIN UDARA MENGGUNAKAN CEILING DUCT DENGAN PENGATURAN SISTEM VRV/F PADA GEDUNG PERKANTORAN 3 LANTAI." JTTM : Jurnal Terapan Teknik Mesin 2, no. 1 (April 17, 2021): 34–42. http://dx.doi.org/10.37373/jttm.v2i1.81.

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In tropical countries, there is a need for air conditioning systems, especially for high-rise buildings to provide comfort for their residents. For this reason, it is necessary to plan an air conditioning system using a ceiling duct with a VRV / F (Variable Refrigerant Volume / FLOW) system setting so that the load and capacity are appropriate and more efficient. In calculating the cooling load, starting from the sensible load and the load, and calculating the size of the ducting. The research method used to plan an air conditioning system using a ceiling duct with VRV / F system settings is the observation method by taking the required data. Perform calculations and analysis with the data obtained. So that after planning the total load on the 5th floor = 270,752.79 Btu / hr (79.3498kW), the 6th floor = 280,568.37 Btu / hr (82,227 kW), and the 7th floor = 229,690.66 Btu / hr (67.3157kW). The size of the ducting supply used is: Height = 75mm-450mm, Width = 75mm - 450mm and the size of the ducting return used is Height = 75mm-450mm, Width = 75mm-450mm. From the planning results, it is determined that the air conditioning system uses a ceiling duct system with VRV / VRF system settings. The advantages are Easy Maintenance, high reliability, large capacity use, space-saving design, different indoor units in one system, and using R410 type refrigerant.

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Bartlewska-Urban, Monika, and Tomasz Strzelecki. "Thermal consolidation of porous medium with a rheological kelvin–voigt skeleton." Studia Geotechnica et Mechanica 34, no. 3 (October 1, 2012): 17–35. http://dx.doi.org/10.2478/sgm031202.

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Abstract This study presents calculations results of thermal consolidation process of the porous medium with the rheological Kelvin-Voigt skeleton, obtained numerically with the use of Flex.PDE software. The investigated calculation scheme consisted of the porous column filled with a liquid. The vertical load was applied to the top surface of the column through a porous plate allowing the free flow of liquid through this surface. Numerical solution is based on compression of the sample at appropriately defined boundary conditions. The aim of this study was to describe the influence of external load and temperature gradient on the deformation tests progress at different values of three parameters: λ, rs and cv. The results obtained, in the context of further research, can also be used for the determination of the influence of other parameters of the state and model parameters on the process of thermo poroelasticity of Biot model with rheological skeleton.

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Flathers, M. B., and G. E. Bache´. "Aerodynamically Induced Radial Forces in a Centrifugal Gas Compressor: Part 2—Computational Investigation." Journal of Engineering for Gas Turbines and Power 121, no. 4 (October 1, 1999): 725–34. http://dx.doi.org/10.1115/1.2818533.

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Radial loads and direction of a centrifugal gas compressor containing a high specific speed mixed flow impeller and a single tongue volute were determined both experimentally and computationally at both design and off-design conditions. The experimental methodology was developed in conjunction with a traditional ASME PTC-10 closed-loop test to determine radial load and direction. The experimental study is detailed in Part 1 of this paper (Moore and Flathers, 1998). The computational method employs a commercially available, fully three-dimensional viscous code to analyze the impeller and the volute interaction. An uncoupled scheme was initially used where the impeller and volute were analyzed as separate models using a common vaneless diffuser geometry. The two calculations were then repeated until the boundary conditions at a chosen location in the common vaneless diffuser were nearly the same. Subsequently, a coupled scheme was used where the entire stage geometry was analyzed in one calculation, thus eliminating the need for manual iteration of the two independent calculations. In addition to radial load and direction information, this computational procedure also provided aerodynamic stage performance. The effect of impeller front face and rear face cavities was also quantified. The paper will discuss computational procedures, including grid generation and boundary conditions, as well as comparisons of the various computational schemes to experiment. The results of this study will show the limitations and benefits of Computational Fluid Dynamics (CFD) for determination of radial load, direction, and aerodynamic stage performance.

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Hu, Ping, Tong Lin, Rui Yang, Xiaocheng Zhu, and Zhaohui Du. "Numerical investigation on flow instabilities in low-pressure steam turbine last stage under different low-load conditions." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 235, no. 6 (February 27, 2021): 1544–62. http://dx.doi.org/10.1177/0957650921997199.

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The modern power generation system requires steam turbines operating at flexible operating points, and flow instabilities readily occur in the low-pressure (LP) last stage under low-load conditions, which may cause failure of the last stage moving blades. Some studies have shown that within this operating range, a shift of the operating point may lead to flow instabilities. Numerical simulation has gradually developed into a popular method for such researches, but it is expensive for a complex model, which has to be balanced between efficiency and accuracy. This work is divided into three parts: Firstly, one of the low-load conditions is selected to provide both URANS model and the Scale-Adaptive Simulation (SAS) model. The results of the two models are compared to evaluate specific flow phenomena; Secondly, through calculations of different low-load conditions, the flow structure and propagation characteristics of instabilities in the last stage are obtained; Finally, flow analysis is applied to explain the formation mechanism of flow instabilities in LP steam turbines. The results show that, the introduction of SAS model increases the randomness of flow over time, but does not fundamentally change the flow instabilities. Flow instabilities take different forms at different flow rate, from rotating instability to rotating stall. The formation of flow instabilities is related to the radial flow in the cascade passages.

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Gianto, Rudy, and Purwoharjono Purwoharjono. "A new method to incorporate three-phase power transformer model into distribution system load flow analysis." International Journal of Applied Power Engineering (IJAPE) 10, no. 3 (September 1, 2021): 262. http://dx.doi.org/10.11591/ijape.v10.i3.pp262-270.

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This paper proposes a new and simple method to incorporate three-phase power transformer model into distribution system load flow (DSLF) analysis. The objective of the present work is to find a robust and efficient technique for modeling and integrating power transformer in the DSLF analysis. The proposed transformer model is derived based on nodal admittance matrix and formulated by using the symmetrical component theory. Load flow formulation in terms of branch currents and nodal voltages is also proposed in this paper to enable integrating the model into the DSLF analysis. Singularity that makes the calculations in forward/backward sweep (FBS) algorithm is difficult to be carried out. It can be avoided in the method. The proposed model is verified by using the standard IEEE test system.

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Zhang, Xi, Xingyu Jia, and Xuan Jiang. "The Effect of Load Control on the Performance of Contra-Rotating Fans." Processes 9, no. 7 (July 16, 2021): 1227. http://dx.doi.org/10.3390/pr9071227.

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In recent years, few studies focused on adjusting the load distribution of contra-rotating fan (CRF) blades. To improve the overall performance of CRFs, we used a design code to build 32 sets of CRFs to determine the effects of three factors—the front and rear rotor load matching, the load distribution of each rotor and the axial distance between the rotors—on the total pressure rise and efficiency of CRFs using numerical calculations. The relationship between the CRF blades load and velocity components was theoretically analyzed using blade element analysis and the forward problem method. According to the performance curve, it can be concluded that the rear rotor (RR) is the key factor that determines the performance of CRFs. Through analyzing Mach number contours from different perspectives, the relationship between velocity and adjustment load was verified. Furthermore, the flow field characteristics for three specific CRFs were explored at the stall points, design points and choke points to reveal their flow mechanisms. This study provides a reference for the CRF blade design method.

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Kriechbaum, Lukas, Philipp Gradl, Romeo Reichenhauser, and Thomas Kienberger. "Modelling Grid Constraints in a Multi-Energy Municipal Energy System Using Cumulative Exergy Consumption Minimisation." Energies 13, no. 15 (July 30, 2020): 3900. http://dx.doi.org/10.3390/en13153900.

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Efficiency measures and the integration of renewable energy sources are key to achieving a sustainable society. The cumulative exergy consumption describes the resource consumption of a product from the raw material to the final utilisation. It includes the exergy expenses for energy infrastructure as well as the imported energy. Since consumers and renewable potentials are usually in different locations, grid restrictions and energy flows have a significant impact on the optimal energy system design. In this paper we will use cumulative exergy minimisation together with load flow calculations to determine the optimal system design of a multi-cell municipal energy system. Two different load flow representations are compared. The network flow model uses transmission efficiencies for heat, gas and electricity flows. The power flow representation uses a linear DC approximated load flow for electricity flows and a MILP (mixed integer linear programming) representation for heat and gas flows to account for the nonlinear pressure loss relation. Although both representations provide comparable overall results, the installed capacities in the individual cells differ significantly. The differences are greatest in well meshed cells, while they are small in stub lines.

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Alazzawi, Omar Kamil Dahham, Mustafa Ahmed Nayyef, and Yasir Abdulhafedh Ahmed. "Transient stability enhancement in the presence of optimally placed D-FACTS." International Journal of Power Electronics and Drive Systems (IJPEDS) 11, no. 3 (September 1, 2020): 1350. http://dx.doi.org/10.11591/ijpeds.v11.i3.pp1350-1359.

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<span lang="EN-US">The power flow in power system can be controlled in an effective method by using FACTS devices through transmission lines. Distributed FACTS represent a new way to overcome these drawbacks. They are cost-effective, light weighted, higher performance and minimization of environmental impact. They are placed in a distribution method and in selected lines in the network according to line flow stability indices based on load flow calculations. In this paper, distributed static series compensator (DSSC) is used in order to attain the required power flow control by modifying the line reactance. They are installed directly on the present H.V transmission lines and as a result does not require H.V insulation. The load flow analysis has been carried using mat lab and the simulation for the purpose of stability by using Power World Simulator software. The results show an enhancement in stability performances of the system over the conventional controllers. </span>

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Vinkovic, Anton, Marko Suhadolc, and Rafael Mihalic. "Current-based models of FACTS devices for three-phase load-flow calculations using the Newton–Raphson method." International Journal of Electrical Power & Energy Systems 45, no. 1 (February 2013): 117–28. http://dx.doi.org/10.1016/j.ijepes.2012.08.070.

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Xiong, Yi Bo, Chun Ming Wang, and Lu Peng. "Numerical Simulation on Combined Deformation of Tip-Loaded Cantilever Beam with Particle Flow Code." Advanced Materials Research 378-379 (October 2011): 31–34. http://dx.doi.org/10.4028/www.scientific.net/amr.378-379.31.

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In order to calculate the combined deformations of an Euler-Bernoulli cantilever beam subjected to bending moment, twisting moment, transverse load and axial load, particle flow code in 3 dimensions (PFC3D) is used with parallel bonds model. The computed deformations, including transverse deflections, rotations about axis, maximum normal and shear stresses, were compared with the analytical beam-theory solution in terms of axial tension, axial compression and none axial load, respectively. Between computed results and analytical beam-theory solution, the error bands are greater than 99.7% at the beam tip, while the error of the transverse deflection of the whole beam is less than 0.6%. So, the PFC3D is able to precisely simulate the combined deformation of cantilever beam, and this work has special reference to engineering calculations and designs when PFC is applied to model the mechanical behaviors of continuum materials.

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Franczyk, Ewelina, Andrzej Gołębiowski, Tadeusz Borowiecki, Paweł Kowalik, and Waldemar Wróbel. "Influence of Steam Reforming Catalyst Geometry on the Performance of Tubular Reformer – Simulation Calculations." Chemical and Process Engineering 36, no. 2 (June 1, 2015): 239–50. http://dx.doi.org/10.1515/cpe-2015-0016.

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Abstract A proper selection of steam reforming catalyst geometry has a direct effect on the efficiency and economy of hydrogen production from natural gas and is a very important technological and engineering issue in terms of process optimisation. This paper determines the influence of widely used seven-hole grain diameter (ranging from 11 to 21 mm), h/d (height/diameter) ratio of catalyst grain and Sh/St (hole surface/total cylinder surface in cross-section) ratio (ranging from 0.13 to 0.37) on the gas load of catalyst bed, gas flow resistance, maximum wall temperature and the risk of catalyst coking. Calculations were based on the one-dimensional pseudo-homogeneous model of a steam reforming tubular reactor, with catalyst parameters derived from our investigations. The process analysis shows that it is advantageous, along the whole reformer tube length, to apply catalyst forms of h/d = 1 ratio, relatively large dimensions, possibly high bed porosity and Sh/St ≈ 0.30-0.37 ratio. It enables a considerable process intensification and the processing of more natural gas at the same flow resistance, despite lower bed activity, without catalyst coking risk. Alternatively, plant pressure drop can be reduced maintaining the same gas load, which translates directly into diminishing the operating costs as a result of lowering power consumption for gas compression.

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Humena, Steven, Frengki Eka Putra Surusa, Amelya Indah Pratiwi, and Rifat Kombu. "Evaluasi Kinerja PLTMH Polohungo 40 KW Terhadap Small Scale Power Load (SSPL)." Jurnal Teknik 19, no. 1 (July 9, 2021): 75–84. http://dx.doi.org/10.37031/jt.v19i1.146.

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The Polohungo Micro-hydro Power Plant (PLTMH) in Polohungo village, Tolangohula District, Gorontalo Regency has several components, namely intake, headrace, forebay, tailrace, penstock, turbines, mechanical equipment systems, mechanical transmission systems, and generators. The increase of demand for electrical power and the limited capacity of the generator was causing suboptimal plant operation. This study aims to evaluate the performance of the 40 kW PLTMH against the electrical load in Polohungo Village, Gorontalo Regency. The evaluation stage began with the calculation of the technical parameter data of the equipment, which was then compared with parameters obtained from measurement. The evaluation results show that the overall condition of the main components such as generators, turbines, and the generator control system was still working well even though there was no history of maintenance. There was a power difference of 12.212 kW or 55.03% between the real-world generated power and theoretically calculated power based on turbine design water flow. Therefore, PLTMH Polohungo was not operating optimally when handling small-scale power loads, where the amount of power generated by theoretical calculations is greater than the amount of power generated when the generator is operating with a water flow rate of 0.02865 m3/second.

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Journal articles on the topic 'Load-flow calculations'

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