High-efficiency Equipment Research Articles

Research on the Green Path of Building Electrical Engineering in the Context of Digitalization

In today's digital era, the greening of building electrical systems has become a crucial path for the sustainable development of the construction industry. Judging from the current research status at home and abroad, although certain achievements have been made, there are still many areas that need further exploration. Digital technologies have brought transformative opportunities to building electrical systems. In the field of intelligent lighting, they can achieve precise dimming and scene adaptive control; in the application of high-efficiency and energy-saving equipment, their performance can be optimized with the help of digital monitoring and regulation; after the digital upgrade of energy management systems, refined energy consumption analysis and intelligent dispatching can be accomplished; in the process of integrating renewable energy with building electrical systems, digital technologies can help solve the problems of intermittency and stability. However, this process is faced with challenges such as technology integration, cost control, standards and regulations, and user awareness. Looking ahead, with technological innovation and policy promotion, the greening of building electrical systems will thrive in the directions of intelligence, high efficiency, and synergy, laying a solid theoretical and practical foundation for the sustainable development in the construction field.

ADJUSTMENT OF THE ELEMENTS OF THE FLOW PART OF THE HIGH-EFFICIENCY OF PUMP- TURBINE

The problem of the development of pumped storage power plants in Ukraine is considered, especially in the conditions of military operations, which damaged the energy infrastructure and created capacity shortage. The pumped storage power plants will help stabilize the power system by storing energy during periods of low load and efficiently using it during peak needs or accidents. All this has a positive impact on the role of energy autonomy and the integration of renewable energy sources. Efficiency increase of the hydro-turbine equipment of the PSPP requires the improvement of the water passage of the reversible hydraulic machines. This work shows that the creation of high-efficiency reversible hydraulic equipment depends on the correct selection of the geometry of the pater passage elements of the reversible hydraulic machines, consequently ensure the necessary level of energy characteristics of the hydraulic equipment. The equation of the optimal mode was used for the calculated assessment of kinematic and energy characteristics, analysis of their formation and search for rational variants that provide the specified requirements for the runner energy characteristics of the reversible hydraulic machines. Calculations are carried out using dimensionless kinematic parameters, which simplifies the process and eliminates the need for complex calculations. The numerical analysis data on the influence of the hydrodynamic parameters of the water passage on the parameters of the optimal mode can be used both for profiling the blade system of the runner, with the aim of improving energy characteristics (increasing power, efficiency level, etc.), and for modifying the blade system. The numerical study method for finding optimal variants of the runner blade system is given. The proposed approach was used to estimate the kinematic and energy characteristics of water passages of Francis turbines, as well as high-head reversible hydraulic machines ОRО200 and ОRО500 (both for basic and modified variants of the water passage).

Effects Of Repeated Cropping Of Moss On Soil Volume and Porosity

The article provides information on the use of different methods of tilling the soil in the care of winter wheat and repeated crops, including the effect of soil volume mass when using cultivation and resource-saving agrotechnology (using the Ilgor-1 unit) and plowing with high-efficiency equipment.

Spray performance simulation and experiment analysis of a greenhouse fixed-pipe twin-fluid cold fogger with different nozzle settings.

High-efficient pesticide application equipment for protected cultivation is scarce. In response, a fixed-pipe twin-fluid clod fogger (FTCF) was proposed as a potential solution. To investigate the optimal nozzle layout and spray performance, a computational fluid dynamics (CFD) model was used to study the airflow distribution and spray deposition of a FTCF with different nozzle settings using the Euler-Lagrange approach. Specifically, two piping configurations, middle-cross-inverted (MCI) and bilateral-malposed-opposite (BMO), were combined with three nozzle spacings (2 m, 3 m, 4 m) resulting in six nozzle settings. Additionally, a greenhouse spray trial was conducted to test the performance of FTCF with the selected nozzle settings and to validate the model. The simulation results revealed that MCI piping configuration exhibited a stronger airflow disturbance compared to BMO configuration, indicating a more significant air-guided effect in the MCI configuration. Combining this finding with the ground droplet distribution analysis of MCI piping configuration, it was observed that MCI-2 m had the lowest coefficient of variation (CV) for ground deposition (20.56%). Consequently, MCI-2 m was determined as the most optimal nozzle setting. Verification results demonstrated a high consistency between experimental and simulated spray deposition results. The FTCF system effectively generated a three-dimensional airflow field throughout the greenhouse environment. Furthermore, jet flow produced by FTCF disrupted the overall airflow pattern within the greenhouse space which facilitated droplet suspension and dispersion. This study provides valuable insights and innovative ideas for enhancing pesticide application technologies in protected cultivations. © 2024 Society of Chemical Industry.

Exploration of Energy-Saving Technologies in Building Electrical System Design

Green energy conservation is the mainstream trend in the current development of the construction industry. The application of energy-saving technology in building electrical system design can effectively reduce energy consumption, avoid unnecessary energy consumption, and truly achieve energy conservation and environmental protection. Based on this, the article elaborates on the principles of energy-saving design in building electrical systems, and actively explores the application of energy-saving technologies from different perspectives such as optimizing power supply and distribution system design, adopting high-efficiency energy-saving lighting equipment, applying renewable energy, promoting smart home technology, and improving the efficiency of building electrical equipment.

Power Supply Status Analysis and Scheme Design of High Efficiency and Rapid Driving Equipment

In the view of the problems of frequent movement and change in the practical application of complete sets of high efficient and rapid driving equipment, a scheme of extending the power supply distance is designed. In this scheme, an intelligent comprehensive regulation device is arranged in the shifting area and a power quality parameter monitoring device is arranged in the combination switch of the device. Real-time and accurate monitoring of the three-phase line voltage and phase Angle during the operation of the equipment and feedback to the intelligent integrated regulation device through optical fiber communication mode. The PLC controller in the intelligent integrated regulation device implements different voltage and phase regulation control strategies according to the voltage and phase Angle values monitored at the head and end. The test results in the plant show that the scheme can improve the terminal voltage of the equipment and achieve the purpose of “shift and change, long distance power supply.

Research on slim-hole drilling technology for shale gas geological survey in China

Over the last 10 years, the China Geological Survey has deployed 137 slim-hole shale gas geological exploration wells for coring entire wellbores. These wells are primarily located in new blocks and geological formations where neighboring well data are insufficient, beyond the scope of developed oil fields in China, or outside of oil and gas company mining-right areas. The drilling rig equipment, coring tools, and core drill bits of slim-hole shale gas drilling technology are different from those associated with traditional petroleum drilling. Many studies have been conducted on non-coring slim-hole drilling technology. This paper focuses on coring technology and drilling safety, summarizing a set of high-efficiency shale gas drilling equipment and technology systems based on geological drilling equipment and techniques (that can be used for solid mineral exploration). We report on: 1) an improved vertical shaft drilling rig adapted to shale gas well control safety; 2) high-efficiency core drilling techniques, focusing on coring tools, and techniques incorporating an inverted tower drilling tool combination, air circulation follow-through technology, and expanded casing technology; 3) research progress on high-efficiency core drill bits, including non-planar tooth polycrystalline diamond compact bits and impregnated diamond core bits, along with their application effects. This research provides substantial advances in drill-core technology and improvements in exploration efficiency. Moreover, it provides a reference frame for well structural design and selection of construction technology for shale gas exploration drilling projects.

Advanced Technologies for Detection and Assessment of Road Degradation State. Experimental and Modeling Approaches

Abstract Detection and classification of degradation types is a fundamental activity in road pavement management. Monitoring activities through manual / visual inspections are time consuming, costly and cause safety issues. The introduction of new high-efficiency equipment for the detection and classification of degradation opens a new perspective in the analysis and management of roads. Thus, the automatic monitoring of the road asset introduces new performance indicators and more complex criteria for classifying problems. In this paper, an analysis is presented by referring to examples of measurements in Romania, detection, and classification of the main types of degradation, study, and capabilities of ACD (Automatic Crack Detection). A numerical and experimental study was also conducted to improve the operational optimization of ACD equipment to increase its usability and performance.

Policies and Energy Efficiency of Heat Recovery Ventilators in South Korea

To reduce national greenhouse gas emissions, the South Korean government has encouraged new energy businesses and implemented policies to reduce energy consumption in buildings, and aims to construct all new buildings as zero-energy buildings by 2025. According to the promotion of policies on passive houses and zero-energy buildings, the thermal insulation and airtight performance of new buildings have been further enhanced. However, to enhance indoor comfort and air quality in new airtight buildings, it is critical to secure an adequate amount of ventilation. Heat recovery ventilators (HRVs) in South Korea have been used for more than 20 years as high-efficiency energy equipment; however, the high-efficiency standard 20 years ago (cooling efficiency 45%, heating efficiency 70%) is still being employed without any change. Most HRVs in the Korean market either meet or exceed this standard. This study examined HRV performance changes from 2010 to 2020 based on the data of 847 HRV performance certifications given by a certification agency. It also analyzed how institutional strategies and related laws contributed to the enhancement of such performance. As HRVs in South Korea are only required to satisfy the pre-defined efficiency criteria, the development and use of HRVs focus more on cost reduction rather than efficiency enhancement. Under such market conditions, it is challenging to research and design highly efficient HRVs along with customer satisfaction. If better market conditions are offered that would welcome HRVs with higher efficiency, the development of better HRVs, as compared to those analyzed in this research study, would be possible.

Review of Wireless RFID Strain Sensing Technology in Structural Health Monitoring.

Strain-based condition evaluation has garnered as a crucial method for the structural health monitoring (SHM) of large-scale engineering structures. The use of traditional wired strain sensors becomes tedious and time-consuming due to their complex wiring operation, more workload, and instrumentation cost to collect sufficient data for condition state evaluation, especially for large-scale engineering structures. The advent of wireless and passive RFID technologies with high efficiency and inexpensive hardware equipment has brought a new era of next-generation intelligent strain monitoring systems for engineering structures. Thus, this study systematically summarizes the recent research progress of cutting-edge RFID strain sensing technologies. Firstly, this study introduces the importance of structural health monitoring and strain sensing. Then, RFID technology is demonstrated including RFID technology's basic working principle and system component composition. Further, the design and application of various kinds of RFID strain sensors in SHM are presented including passive RFID strain sensing technology, active RFID strain sensing technology, semi-passive RFID strain sensing technology, Ultra High-frequency RFID strain sensing technology, chipless RFID strain sensing technology, and wireless strain sensing based on multi-sensory RFID system, etc., expounding their advantages, disadvantages, and application status. To the authors' knowledge, the study initially provides a systematic comprehensive review of a suite of RFID strain sensing technology that has been developed in recent years within the context of structural health monitoring.

Energy saving through modifications of the parallel pump schedule at a pumping station: A case study

Diverse state-of-the-art methods can be utilized to reduce energy consumption in water supply and distribution systems, including using high-efficiency equipment, shifting energy use away from peak demand times, energy recovery and storage devices, and renewable energy. However, the benefit of using high efficiency equipment can sometimes never be completely realized, as the performance of the individual pumps within a site can be reduced from optimal owing to a variety of reasons: a lower operating rate of the water treatment plant than the design flow rate, hydraulic conditions such as pipeline resistance or determined pressure, and pump scheduling. This research focused on optimizing pump scheduling through real-time monitoring utilizing smart temperature and pressure sensors, wireless low-power data communicators, and a pump data analysis algorithm to determine the hydraulic efficiency from thermodynamic state variables with subsequent parallel pump optimization. Thermodynamic pump performance measurements provided real-time information, including flow rate, specific power, and pump efficiency, in both individual and parallel pump operations. Evaluation of the specific power under diverse parallel pump operation scenarios demonstrated a variation of 0.115–0.140 kWh/m3 in the range of 7800–10,100 m3/h. However, the deviation in specific power was more than 17 % when operating at less than 7800 m3/h and more than 10,000 m3/h. The summary of the pump combination operation suggested that energy could be saved by up to 15 % by optimum pump scheduling, that is, small capital investment, simple optimization of control through thermodynamic state variable measurement, analysis, and feedback.

Energy saving potential pre-estimation approach for air-source heat pump usage in China based on thermodynamic irreversibility

Building sector accounts for a substantial part of energy consumption (EC) and carbon emissions, mainly serving for building services engineering systems. As a known advanced high-efficiency equipment, air source heat pump (ASHP) has been increasingly used for indoor heating ventilation and air conditioning (HVAC) for residential and public buildings. Thus how to pre-estimate the energy saving potential (ESP) for given ASHPs under different climatic conditions is of high value for practical engineering application. In this paper, upon thermodynamic perfectibility conception, a simplified ASHP model is proposed to simulate its dynamic thermal performance according to the disparity between real equipment and the ideal reverse Carnot cycle. Moreover, a novel thermodynamic approach is proposed to pre-estimate and compare the seasoning-based ESPs of ASHP used for both heating and cooling. For illustrative examples, a typical public building is chosen, and the AHSP-ESPs are obtained and analyzed for five cities of different climate zones in China (Qiqihar, Beijing, Chengdu, Kunming, and Guangzhou). Preliminary research results show that lower/higher ambient temperatures contribute to higher heating/cooling ESPs respectively. However, the correlation between building EC and thermodynamic perfectibility is in inverse proportion. At first, building EC decreases rapidly with the increase of thermodynamic perfectibility, but as the thermal performance of ASHP gets closer to the corresponding ideal ones, the impact of thermodynamic perfectibility on building EC gradually decreases. This work is of great significance in understanding the regional applicability of ASHP and building EC, and providing application references for real ASHP usage in building sectors.

Optimization of Low-Carbon and Highly Efficient Turning Production Equipment Selection Based on Beetle Antennae Search Algorithm (BAS)

Reducing carbon emission and raising efficient production are the important goals of modern enterprise production process. The same product can be produced by a variety of equipment, and the carbon emissions and processing time of different equipment vary greatly. Choosing suitable production equipment is an important method for manufacturing enterprises to achieve the efficient emission reduction of production process. However, the traditional production equipment selection mode only gives qualitative results, and it is difficult to provide effective advice for enterprises to choose suitable equipment under the needs of carbon neutrality. To solve this problem, this paper systematically analyzes carbon emission and the time of the turning production process, and a unified calculation model for carbon emission and efficient production of multi-type processing equipment is established. The important point of the article is to research the diversity among between carbon emissions and efficiency levels of the same product produced by different devices. The carbon emissions and efficiency levels of different kinds of equipment can be calculated by the BAS algorithm. By turning a shaft part as an example, the results show that this method can calculate the optimal value of carbon emissions and efficiency of the same product produced by different equipment and can provide suggestions for enterprises to select appropriate equipment for low-carbon and efficient production. This paper provides a reference for further research on the quantitative calculation model for the selection of high-efficiency and low-carbon production equipment.

A Rational Plan of Energy Performance Contracting in an Educational Building: A Case Study

Energy performance contracting (EPC) is the best solution for an educational building to implement energy conservation measures (ECMs) because of its high capital expenditure and operational expenditure needed for retrofit and maintenance. It is also considered a win–win mechanism for organising building energy efficiency retrofit projects. It aims to assist educational buildings in acquiring new high-efficiency equipment and maximising energy use reduction, as guaranteed by energy service company (ESCO). This study developed an EPC model using regression analysis, in which the inputs are based on the data collected during the preliminary energy audit in University A. As a result, with a quantum sharing ratio of 0.95/0.5 for ESCO/University A, the forecasted energy savings from the proposed ECMs, chiller optimisation and replacement, lighting retrofit, and energy management system are estimated to save 25.6% energy use, which reduces 5,672,057 kilowatt-hour (kWh) in electricity consumption; saves RM 2,762,291.76/year; carbon dioxide (CO2) mitigation equal to 3,771,061.22 kgCO2/year; return of investment of 4.2 years with a 5% interest rate; and building energy intensity of 93.55 kWh/m2/year. A sensitivity analysis of various quantum sharing ratios found that the saving value of ESCO is inversely proportional to that of University A as the client when the quantum sharing ratio for the former is increasing.

Progress in Adsorptive Removal of Volatile Organic Compounds by Zeolites

Volatile Organic Compounds (VOCs) are a class of pollutants that have recently received much attention in atmospheric and indoor air pollution problems. They are precursors for PM2.5 and ozone generation. The removal of VOCs emitted from exhaust gases is an urgent problem to solve air pollution. Adsorption is one of the most promising VOC abatement technologies, with the advantages of high purification efficiency, low cost, and simple equipment. The adsorbent plays a critical role in VOCs removal efficiency. Zeolite is a rapidly developing material due to its highly ordered and flexible microporous structure, good stability, and abundant surface modification. In this paper, the influence of zeolite properties, including framework structure, pore properties, and surface cations, on VOCs adsorption performance is analyzed. The VOCs adsorption performance on different zeolite adsorbents in the presence of water vapor is compared. The influential factors on the mass transfer kinetic properties of VOCs adsorption are summarized. Finally, an overview of zeolite honeycomb adsorbent applications for industrial use is presented, including multi-tower fixed bed adsorption and zeolite rotor adsorption.

Structural stress analysis of hybrid heat exchangers in the S-CO2 power cycle for marine waste heat recovery

Due to its high thermodynamic efficiency and small equipment size, the S-CO2 Brayton power cycle is a leading candidate for ship waste heat utilization. The hybrid heat exchanger formed by diffusion bonding of fins and etched plates can be used for heat exchange between the high temperature flue gas and the high pressure S-CO2. However, the law of structural strength is not clear for the hybrid heat exchanger. It is critical to carry out structural stress analysis. In this study, to assess the structural strength of the hybrid heat exchanger, the FEM was used and compared with a currently used method from ASME codes. The results show that the thermal stress caused by the temperature gradient is independent of the absolute temperature value. The change in the supercritical carbon pressure in the etched channel affects the mechanical stress more than the exhaust gas in the fin channel. Under design conditions, thermal stress and mechanical stress are equally important to the total stress of the hybrid heat exchanger. Moreover, the total stress is not a simple numerical superposition of thermal stress and mechanical stress but instead indicates a complex effect. From the FEM results, the etched channel exit that withstands a higher pressure load is the weakest point in the hybrid heat exchanger core. The FEM is a more comprehensive means for structural assessment than the ASME codes. This research can provide guidance for structural stress analysis of hybrid heat exchangers

THE COMPUTER MODELING OF CLASS -D AND -DE SWITCHING-MODE POWER AMPLIFIERS FOR VHF DIGITAL RADIO BROADCAST EQUIPMENT

Currently the transition to digital VHF radio broadcasting is being discussed more and more in different countries, which requires the design of new radio broadcast equipment devices. In classical method of amplifying the power of complex radio signals with a variable envelope, the new broadcast equipment will lose significantly to the existing broadcast equipment with frequency-modulated signal in many energy parameters. The most the promising ways to build high-efficiency broadcast equipment devices of complex radio signals with amplitude-phase modulation and high peak-factor are synthetic methods of linear amplification of radio frequency power (for example, basing on the scheme of L. Kahn) by using high-efficiency switching-mode circuits of powerful amplification. The present state of development of powerful radio-frequency transistors allows to assume that in the near future in the VHF-band switching-mode power amplifiers of Class -D and -F, which will be suitable for building digital radio broadcast equipment with the polar architecture of L. Kahn, will be everywhere used. These switching-mode amplifiers, in contrast to higher-frequency Class-E circuits, supply more steady characteristics in the frequency band. But when developing such broadcast equipment, it is also reasonable to deal with modified switching-mode power amplifiers of the Class -DE and -FE. The article deals with the questions of the computer modeling of switching- mode power amplifiers of Class -D and -DE in relation to the design of VHF radio broadcast equipment.

Optimization of a novel vacuum sublimation-rehydration thawing process.

To better guarantee the quality of the thawed meat, maximize the thawing rate, and minimize the system energy consumption, the multiparameter and multi-objective coupling optimizations for the newly proposed vacuum sublimation-rehydration thawing (VSRT) process was conducted. The polynomial nonlinear regression equations of single and comprehensive objectives were established by the central composite rotatable design, and the corresponding test of fitting degree and the analysis of influencing factors order were carried out. Furthermore, the interaction effects of influencing factors were investigated through the response surface methodology and were experimentally validated to obtain the optimal process parameters. The results showed that the established regression equations were in good agreement with the experimental values. For the different objectives, there were great differences in the influence order and interaction of factors. In the sublimation and rehydration stages, there existed an optimal region in the response surface to achieve a better value for the single and comprehensive objectives. When the sublimation time was 19min, the heating plate temperature was 26°C, the rehydration water volume was 1634ml, the rehydration water temperature was 29°C, the thawing time was relatively short (1.00h), and the thawing loss (1.19%), the total color difference (1.02), and the system-specific energy consumption (0.026kWh/kg) were relatively low. The comprehensive performance of the VSRT system reached the best state. PRACTICAL APPLICATION: The purpose of this work is to make the novel vacuum sublimation-rehydration thawing method not only better guarantee the quality of thawed meat but also maximize the thawing rate and minimize the energy consumption of the system, which can provide a new idea and reference for the development of new high-efficiency thawing equipment.

Long video-based action segmentation for earthmoving excavators using improved Temporal Convolutional Network models

Earthwork excavator, as an all-terrain and high-efficiency earthwork excavation equipment, has been widely used in earthwork sites. It is very necessary to analyze the work of earthmoving excavator by means of machine vision. In this paper, the action segmentation method based on long video was applied to the analysis and recogniton of the excavator’s action, and compared with other two current best action segmentation models using the real construction site video. Firstly, the sequence features of the excavator’s work video obtained at the cnstruction site was extracted through 3D convolution method, and then two differernt networks with the extracted sequence features were trained and tested. The experimental results showed that the average frame accuracy of MS-TCN model and ASRF model in excavator action segmentation were 82.6490% and 86.1042% respectively. However, for the recognition task under different working environment, the performance of the two models is quite different. The experimental results manifest that the motion segmentation model based on long video reached good results in excavator motion recognition in earthmoving operation. And it is helpful to analyze the long video working behavior sequence of excavator. This research contributes to the identification of critical elements that explains serial action and to the development of a new application scenario for vision-based behavior segmentation network. Additionally, the results of this study were helpful to automatically analyze the working efficiency and monitor the productivity of earthmoving excavators. Using this kind of data-driven decision can improve the work efficiency of earthmoving excavator and promote the project progress.

Dynamic characteristics and control strategies of the supercritical CO2 Brayton cycle tailored for the new generation concentrating solar power

The supercritical CO2 (sCO2) Brayton cycle has the advantages of high efficiency, good flexibility and compact equipment, and is widely regarded as the ideal power cycle for the new generation concentrating solar power (CSP). The application scenario of the CSP determines that the unit's fast peak shaving capability must be considered. In this paper, a dynamic simulation model was developed for an indirect-heated 800 °C/550 °C sCO2 CSP test plant, containing a particle heat storage system. The effects of control modes of heating power, cooling power, mass flow rate (m), turbine rotational speed and sCO2 inventory on the system dynamic characteristics were researched. It was found that the control mode of changing particle/water mass flow rate had a significantly faster response speed than changing temperature. Using the turbine optimal rotational speed control mode could improve the net cycle efficiency from 15.30% to 16.12%, in a continuous linear load reduction process. The sCO2 inventory control module played a crucial role in limiting the fluctuation of compressor inlet pressure. The regulation mode of changing m and turbine inlet temperature (T4) synchronously and that of changing m with constant T4 were all proved to achieve the goal of fast peak shaving well, but the latter one was safer, which could greatly limit the temperature change rate of sCO2 and equipment in the fast peak shaving process. Our work not only offers an operation solution for the sCO2 CSP test plant, but also gives guidance for the efficient, flexible and safe design of the third generation CSP plants.