Inter-stage performance and energy characteristics analysis of electric submersible pump based on entropy production theory

The electric submersible pump(ESP) is a crucial apparatus utilized for lifting in the oil extraction process.Its lifting capacity is enhanced by the multi-stage tandem structure, but variations in energy characteristics and internal flow across stages are also introduced. In this study, the inter-stage variability of energy characteristics in ESP hydraulic systems is investigated through entropy production(EP) analysis,which incorporates numerical simulations and experimental validation. The EP theory facilitates the quantification of energy loss in each computational subdomain at all ESP stages, establishing a correlation between microscopic flow structure and energy dissipation within the system. Furthermore, the underlying causes of inter-stage variability in ESP hydraulic systems are examined, and the advantages and disadvantages of applying the EP theory in this context are evaluated. Consistent energy characteristics within the ESP, aligned with the distribution of internal flow structure, are provided by the EP theory, as demonstrated by our results. The EP theory also enables the quantitative analysis of internal flow losses and complements existing performance analysis methods to map the internal flow structure to hydraulic losses. Nonetheless, an inconsistency between the energy characterization based on EP theory and the traditional efficiency index when reflecting inter-stage differences is identified. This inconsistency arises from the exclusive focus of the EP theory on flow losses within the flow field, disregarding the quantification of external energy input to the flow field. This study provides a reference for the optimization of EP theory in rotating machinery while deeply investigating the energy dissipation characteristics of multistage hydraulic system, which has certain theoretical and practical significance.

Magnetic Field Curves and Magnetic Equipotential Surfaces around Crossing Electrical Wires Replacing Classical Magnetic Field Lines

This article is based on a recent model specifically defining magnetic field values around electrical wires. With this model, calculations of field around parallel wires were obtained. Now, this model is extended with the new concept of magnetic equipotential surface to magnetic field curves around crossing wires. Cases of single, double, and triple wires are described. Subsequent article will be conducted for more general scenarios where wires are neither infinite nor parallel.

Current State of Energy Production in Cameroon and Projection for 2035

The low electricity supply rate is a major cause of underdevelopment in Cameroon. To address this issue, Cameroon outlined a strategy in 2003 aiming for a production capacity of 3000 MW by 2020. However, by 2020, production had only reached 1040 MW, leading Cameroon to devise a new national energy sector development strategy targeting 5000 MW by 2035. This paper provides an overview of the current state of energy production and projects future output by 2035. Scientific articles and investigative reports on energy production in Cameroon have enabled an assessment of the current electrical energy production. The 2035 production estimate is based on the Energy Sector Development Projects (PDSEN) report in Cameroon. The current production is estimated at around 1600 MW. Considering the ongoing construction of power plants, future projects, and financing delays, achieving the 5000 MW goal by 2035 appears challenging. Nonetheless, diversifying energy production sources could bring Cameroon closer to this target.

China's Processing Trade Development for Mechanical and Electrical Products

Since the launch of the economic reform and opening to the outside world, China has seen rapid growth in its export of mechanical and electrical products, with its export

Seize the Opportunity and Make Efforts to Increase Zhejiang's Export of Mechanical and Electrical Products

Zhejiang’s machine-building industryhas made sustained efforts to increase itsexports through the combination ofindustry and trade. In the past decade,Zhejiang’s export volume of mechanicaland electrical products has increased over 10times, becoming the leading exports fromthe province. Zhejiang has thereforebecome an important province exportingmachinery in China.

Microbial-driven ectopic uranium extraction with net electrical energy production

The extraction of uranium (U) from U-bearing wastewater is of paramount importance for mitigating negative environmental impacts and recovering U resources. Microbial reduction of soluble hexavalent uranium (U(VI)) to insoluble tetravalent uranium (U(IV)) holds immense potential for this purpose, but its practical application has been impeded by the challenges associated with managing U-bacterial mixtures and the biotoxicity of U. To address these challenges, we present a novel spontaneous microbial electrochemical (SMEC) method that spatially decoupled the microbial oxidation reaction and the U(VI) reduction reaction. Our results demonstrated stable and efficient U extraction with net electrical energy production, which was achieved with both synthetic and real wastewater. U(VI) removal occurred via diffusion-controlled U(VI)-to-U(IV) reduction-precipitation at the cathode, and the UIVO_(2) deposited on the surface of the cathode contributed to the stability and durability of the abiotic U(VI) reduction. Metagenomic sequencing revealed the formation of efficient electroactive communities on the anodic biofilm and enrichment of the key functional genes and metabolic pathways involved in electron transfer, energy metabolism, the TCA cycle, and acetate metabolism, which indicated the ectopic reduction of U(VI) at the cathode. Our study represents a significant advancement in the cost-effective recovery of U from U(VI)-bearing wastewater and may open a new avenue for sustainable uranium extraction.

Choice of Site for the Installation of Photovoltaic Solar Power Plants in Senegal: Consequences on Electricity Production

A theoretical analysis of the electricity production of a photovoltaic solar power plant of 22 MW for different sites in Senegal is presented. The study is carried out in two coastal regions (Dakar and Saint-Louis) and two continental regions (Mbacké and Linguère). This study is done using the RET Screen clean energy project management software climate data. The amount of electricity exported to the grid is calculated for each site. The results show that the climatic conditions of the coastal and continental regions are different from November to June. From July to October, which corresponds to the rainy season in Senegal, the climatic conditions of the coastal and continental regions are similar. The results also show that although the efficiency of photovoltaic modules is better on the coast, electricity production varies little from one site to another. Climate conditions in Senegal therefore have no impact on electricity production.

Production prediction for fracture-vug carbonate reservoirs using electric imaging logging data

Considering the fluid flow non-darcy characteristics in fracture-vug carbonate reservoirs, a new multi-scale conduit flow model production prediction method for fracture-vug carbonate reservoirs was presented using image segmentation technique of electric imaging logging data. Firstly, based on Hagen-Poiseuille's law of incompressible fluid flow and the different cross-sectional areas in single fractures and vugs in carbonate reservoirs, a multi-scale conduit flow model for fracture-vug carbonate reservoir was established, and a multi-scale conduit radial fluid flow equation was deduced. Then, conduit flow production index was introduced. The conduit flow production index was calculated using fracture-vug area extracted from the result of electrical image segmentation. Finally, production prediction of fracture-vug carbonate reservoir was realized by using electric imaging logging data. The method has been applied to Ordovician fracture-vug carbonate reservoirs in the Tabei area, and the predicted results are in good agreement with the oil testing data.

Product Specification Analysis for Modular Product Design Using Big Sales Data

Big data on product sales are an emerging resource for supporting modular product design to meet diversified customers’requirements of product specification combinations.To better facilitate decision-making of modular product design,correlations among specifications and components originated from customers’conscious and subconscious preferences can be investigated by using big data on product sales.This study proposes a framework and the associated methods for supporting modular product design decisions based on correlation analysis of product specifications and components using big sales data.The correlations of the product specifications are determined by analyzing the collected product sales data.By building the relations between the product components and specifications,a matrix for measuring the correlation among product components is formed for component clustering.Six rules for supporting the decision making of modular product design are proposed based on the frequency analysis of the specification values per component cluster.A case study of electric vehicles illustrates the application of the proposed method.

Vegetative Development of <i>Sparassis crispa</i>in Various Growth Conditions and Effect of Electric Pulse Simulation on Its Fruit Body Production

This study was carried out to detect the favorable mycelial growth conditions and effect of electric pulse stimulation on fruit body production of SC-1 strain of Sparassis crispa. The optimum growth in PDA was found at 25°C (67 mm colony diameter in 28 days) followed by 20°C (63 mm colony diameter in 28 days). There was no mycelial growth at 35°C. The most favourable initial media pH range was found to be 5 - 7 and colony diameter measurements were not statistically different among these pH values (p > 0.05). However, the highest growth was obtained at pH 6 (57 mm colony diameter in 28 days). A basal medium composed of 0.05 g MgSO4, 0.46 g KH2PO4, 1.0 g K2HPO4, 120 μg thiamine-HCl, 20 g agar and 1000 ml of distilled water was used to investigate growth response of S. crispato different carbon and nitrogen sources. In 28 days, fructose and glucose exhibited best growth (49.4 mm and 31.6 mm colony diameters respectively) and there was no growth on the basal medium supplemented with galactose. Basal medium supplemented with glycine and alanine as nitrogen sources resulted in best growth, 54.4 mm and 50.5 mm colony diameters respectively. There was no mycelial growth in culture medium supplemented with ammonium acetate, ammonium phosphate, arginine and histidine. Electric pulse stimulation improved the fruiting body production. The yields obtained from all bottles in which electric pulse was applied were significantly higher than the yields from the bottles in which electric pulse was not applied. The percent increases of fresh weight yield from control on 100, 120, 130, and 170 kilovolts were 36%, 44%, 75% and 81% respectively. As regard to dry weight yield, the percent increases from control on 100, 120, 130, and 170 kilovolts were 27%, 54%, 63% and 67% respectively.

Optimization of double chamber microbial fuel cell for domestic wastewater treatment and electricity production

Microbial fuel cells(M FCs)represent a new approach for treating w aste w ater along w ith electricity production.The present study addressed electricity production from domestic w astew ater using a mediator-less double chamber M FC.The electricity production w as monitored under different operational conditions for both summer and w inter samples.Optimization of the anodic and cathodic chambers resulted in a maximal current of 0.784 and 0.645 m A w ith the maximal pow er intensity of 209 and 117 m W/m2in pow er duration of 24 h for the summer and w inter samples,respectively.Scanning electron microscopy show ed that the bacterial biofilm formation on the anode w as denser for the summer sample than that w hen the w inter sample w as used,so w as the total bacterial count.Therefore,samples taken during summer w ere considered better in electricity production and w aste w ater treatment than those taken during w inter basically because of the high microbial load during the hot season.In parallel,there w as a decrease in both biological oxygen demand(BOD5)and chemical oxygen demand(COD)values which reached 71.8%and 72.85%,respectively at the end of the operation process for the summer sample,w hile there w as no evident decrease for the w inter sample.Optimizing the operating conditions not only increased the potential of using domestic w aste w ater in microbial fuel cells to produce electricity,but also improved the quality of the domestic w aste w ater.

Impact of Electricity Shortages on Productivity: Evidence from Manufacturing Industries

Electricity shortages present a significant constraint on manufacturers,who rely on electricity as an important input into production.In China,electricity supply has been growing rapidly.However,the rapid industrialization sometimes makes the power supply still unable to meet the demand.Using a survey of 1673 Chinese manufacturing firms,this paper explores how firms response to electricity shortages and its impact on productivity.We find that self-generation of electricity and investment in Research and Development(R&D)have significant positive relationships with electricity shortages.Further investigations reveal that self-generation is the most common way to deal with electricity shortages.However,it aggravates productivity loss.Though investment in Research and Development can promote productivity,it cannot offset the negative impact of electricity shortages on productivity.Analyses on subsamples show heterogeneity in the impacts of electricity shortages across firms.In particular,large firms are more inclined to invest in R&D than small and medium-sized firms are.They are also the one who suffer significant productivity loss due to self-generation of electricity.Though it is possible for medium-sized firms to reduce productivity loss through R&D,they are not likely to invest in R&D as a response to electricity shortages.This study illustrates that firms can hardly have effective solutions to electricity shortages,and policy makers should take great efforts to increase electricity supply.

Causal Relationship Between Electricity Production and Macroeconomic Indicators:Cross Countries Analysis

Today,many developing countries are facing severe shortage of electricity production in their economies which results into a widening gap between electricity production and consumption.This paper employs three-step methodology of Unit Root,Johansen Cointegration,and Vector Error Correction Mechanism to examine whether there exists short-,long-run,uni-,or bi-directional causality among economic growth,electricity production,and inflation for three South Asian economies namely,India,Pakistan,and Bangladesh covering the period 1973-2014.This paper finds the neutrality hypothesis in the short run for India,Pakistan,and Bangladesh.For the long run,the test result indicates that different hypothesis exists for the three countries under the analysis.This implies that policies and strategies for increasing the installed capacity of electricity generation can lead towards prosperous economic growth in the long run.

Assessment of Electricity Productivity in China:Regional Differences and Convergence

Electricity productivity is regarded as a major assessment indicator in the design of energy saving policies,given that China has entered a“New Normal”of economic development.In fact,enhancing electricity productivity in an all-round way,as is one of the binding indicators for energy and environmental issues,means that non-growth target of total electric energy consumption in the economic development is feasible.The Gini coefficient,Theil index,and Mean log deviation are utilized to measure regional differences in China’s electricity productivity from 1997 to 2016 in five regions,and conditionalβconvergence is empirically analyzed with the spatial Durbin model.The results show that:(1)China’s electricity productivity is improving,while the overall feature is that the eastern area has a higher efficiency than the western area.(2)The difference in electricity productivity is the smallest in the northeast and the largest in the northwest.Interregional difference plays an important role and is the main cause for the differences.(3)The electricity productivity in China exhibitsβconvergence,except for the northwest.The positive driving factor is urbanization level(0.0485%),and the negative driving factor is FDI(–0.0104%).Moreover,the urbanization rate(0.0669%),foreign direct investment(0.0960%),and the industrial structure(–0.0769%)have a spatial spillover effect on improving regional electricity productivity.Based on this conclusion,the study provides some recommendations for saving energy policy design in China’s power industry.

The Usage of Saccharomyces cerevisiae in Microbial Fuel Cell System for Electricity Energy Production

A laboratory-scale MFC （microbial fuel cell） was studied in order to determine the capacity and the efficiency of electricity production in microbial fuel cell system by using microorganisms. The medium used is an isolated culture ofSaccharomces cereviciae. A number of media has been evaluated to provide the best growth phase for Saccharomces cereviciae using optical density method with spectrophotometer at a wavelength of 550 nm. Nation 117, Lyntech, USA is used as proton exchange membrane and graphites with surface area 1.46 x 10.3 m2 are used as cathodes. Cathode chamber is fulfilled with a mixture of electrolyte compounds K3Fe（CN）6 and a buffer solution. Microbes that have been cultured are applied into anode chamber. A number of factors need to be controlled so that microbes can generate electrical energy efficiently, such as by measuring the degree of acidity and DO value in the anode compartment. In this research, the usage of riboflavin as a mediator is also investigated, while the usage of riboflavin increase production efficiency 53.90% compare to MFC without riboflavin as a mediator.

Compact Electric Energy Storage for Marine Vehicles Using on-Board Hydrogen Production

The use of electric energy in marine vessels has been increasing in recent years. In general, it is motivated by the low ecological impact. However, in the case of underwater vehicles it is functionally essential. The objective of this study is to demonstrate the advantage of electric power generation and storage based on on-board hydrogen generation via the reaction between activated aluminum and water and application of the hydrogen in a fuel cell. The original activation process enabling a spontaneous reaction with water to produce hydrogen as well as a parametric study of hydrogen generation rate and yield are briefly described. The potential increase in specific energy （energy per unit mass） and energy density （energy per unit volume） vs. batteries and other means of hydrogen storage is presented. It is shown that the use of the present technology may result in a substantial increase of specific electric energy along with a reduction in volume or an increase in operating time for the same overall mass of energy storage and generation system.

Research on the reliability of the electromechanical products based on the fuzzy theory

Mechanical and electrical products are more and more widely used in all the fields of the society. With the increase in the degree of automation and miniaturization, the structure of many mechanical and electrical products is becoming more and more complex, and the conditions of the use are also increasingly harsh, and therefore more and more product reliability issues are arising, and the reliability technology is being paid more and more attention to. In this paper, aiming at the mechanical and electtical products, from the three aspects of reliability management, reliability design and analysis, and reliability test and evaluation, the reliability research is preliminary studied.

Standardizing the International Bidding System for Chinese Machinery and Electric Products

Inthemid-1980s,ChinaintroducedtheinternationalhiddinqgvstAnimportingitsmachineryandelectricalproducts.TOday,ithasatotalof39institutionsresponsiblefortheirtenderingbusiness.Callingfortenderscanbeenmistedtoanysuchinstitutionbyanenterprise.Thesourcesoff...