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Clamp-on ultrasonic flowmeters serve as an important tool for on-site testing of gas flow meters. However, its accuracy is significantly affected by the actual flow field, thus limiting its application scenarios. To address this issue, this study focuses on typical industrial disturbance structures and obtains the evolution and distribution of non-ideal flow fields downstream of disturbances through experiments and numerical simulations, as well as their effects on velocity and flow measurement errors. The results indicate that when traditional reflection or diagonal measurements were used in the downstream of disturbances, the flow deviation was largely dependent on the installation position and angle of the clamp-on ultrasonic flowmeter. This introduced significant uncertainty and bias, rendering it impossible to correct measurement results through quantitative coefficients. Utilizing a dual-channel measurement method can enhance measurement accuracy. When two sets of sensors perpendicular to each other were used to combine the reflection measurement path, the deviation fluctuation downstream of disturbances can be effectively controlled within the range of ±2%, irrespective of the installation angle. This measurement approach significantly reduced the distance limitations on the distance of the straight pipe section during the use of clamp-on ultrasonic flowmeters.

A prefabricated pumping station is a new type of pumping station that plays an important role in the construction of sponge cities in developing countries. It solves the problem of urban water-logging and makes great contributions to the sustainable development of water resources. In order to research the influence of different installation positions of pumps on the internal hydraulic performance of a prefabricated pumping station, based on ANSYS software, the computational fluid dynamics (CFD) numerical simulation method was used to analyze the internal flow state of the prefabricated pump station. In this research, the optimal geometric parameters of pump installation in a prefabricated pumping station are given. The results show that when the distance between the connecting line of two pumps and the center of the sump is L = 0.2 R, the distance between the two pumps is S = 0.6 R, and the suspension height of the two pumps is H = 0.6 D, the internal flow pattern of the prefabricated pump station is better. (R is the cross-sectional radius of the sump and D is the diameter of the nozzle of the pump horn.) These research results have certain guiding significance for improvement of the hydraulic performance and operation efficiency of prefabricated pump stations. They also provide a theoretical basis for parameter selection for prefabricated pumping stations.

For horizontal-axis wind turbines, wind turbines typically alignment nacelle to the wind using yaw system, realizing max energy capture. If the wind turbine’s nacelle has a large error to the wind, the captured wind energy loss will be large, and it will also cause an increase in the load of the unit, which will pose a major risk to the safety of the wind turbine. Affecting the wind measurement error in addition to the performance of the sensor itself, the installation position of the wind measurement equipment also accounts for an important factor, this paper on the basis of the calculation of fluid dynamics simulation results, through the lateral and longitudinal comparison of the simulation results, pointed out the best installation location of the wind direction sensor, optimize the loss caused by wind measurement error of wind turbine in design, and provide guidance for the installation of the wind direction sensor on site.

The solar cavity heat absorber is the core component of a solar thermal power generation system; its structure and installation position directly affect the efficiency of the heat absorber. To study the influence of these factors on the performance of the heat absorber, in this paper, a numerical simulation of dish solar collector optics is constructed based on the Monte Carlo method, and the distribution characteristics of heat flux density under different heat absorber structures and installation positions are analyzed. The results show that the heat flux density on the inner wall surface of the absorber has a linear relationship with the solar radiation intensity; under the same cavity depth, the energy received by the cylindrical, dome, and inverted cone absorbers is easier to deposit on the top. The heat flux density on the top surface of the inner cavity presents an annular distribution law. As the position of the heat absorber moves away from the dish solar collector surface, the top energy is gradually transferred to the circumferential surface. When the heat absorber is in position B, the total power ratio of different heat absorber structures entering the cavity can reach 99%. At this time, the circular type of heat absorber is more conducive to the full heat absorption of the working medium.

Choking is a common method for controlling severe slugging in offshore oil and gas pipeline–riser systems. By combining experimental data with OLGA simulation, the influence of the installation position of the choke valve on control performance is analyzed. The results indicate that installing the valve near the riser top enables the elimination of slug flow at a larger valve opening, and can mitigate the pressure rise in the pipeline and facilitate valve selection for the slug control system, thus improving the safety and stability of the oil and gas transportation system. The mechanism analysis concludes that the principle for optimizing the valve installation position is to suppress liquid accumulation and liquid slug formation in the pipe section on an FPSO unit and to promote gas outflow. In a practical offshore pipeline case, the results under low-liquid-production-rate conditions are consistent with the simulated trends of the laboratory pipeline. However, in the case of the biggest production rate, the control performance at different installation positions tends to converge. The findings of this study can provide a reference for designing slug control strategies on offshore oil and gas production platforms.

Obtaining a reasonable mold flow field for casting slabs with different sections is challenging by solely modifying the nozzle structure and continuous casting process. Research was conducted on small-sectioned (1000 mm × 220 mm) and large-sectioned (3250 mm × 220 mm) slab continuous casting molds with a fixed nozzle form (concave bottom nozzle, side port inclination angle of 0°). A three-dimensional electromagnetic model is established to analyze the current frequency, installation position, and rotation angle under the active deceleration mode and acceleration mode. The results indicate that, regardless of the deceleration mode for small-sectioned slabs or the acceleration mode for large-sectioned slabs, the magnetic flux density in the mold decreases with increasing current frequency. However, the maximum electromagnetic force initially increases and then decreases, suggesting that both electromagnetic modes have the same optimal current frequency (3 Hz). The optimal mechanical design parameters for the deceleration mode of electromagnetic variable flow device (EM-VFD) with the small-sectioned slab are as follows: installation position Z  = 115 mm and rotation angle of 15°, ensuring that the maximum electromagnetic force is applied to the nozzle jet area. For the acceleration mode of the large-sectioned slab EM-VFD, the optimal mechanical design parameters are as follows: Z  = 115 mm and rotation angle of 10°, ensuring that the maximum electromagnetic force is applied to 1/4 and 3/4 areas of the wide face. These findings indicate that the new electromagnetic variable flow device, which can actively adjust the flow rate and angle of the steel even under given working conditions, provides the possibility for reasonable control of the mold’s flow field.

As a part of the new energy development trend, distributed power generation may fully utilize a variety of decentralized energy sources. Buildings close to the installation location, besides, may have a considerable impact on the wind turbines’ operation. Using a combined vertical axis wind turbine with an S-shaped lift outer blade and Φ-shaped drag inner blade, this paper investigates how a novel type of upstream wall interacts with the incident wind at various speeds, the influence region of the turbulent vortex, and performance variation. The results demonstrate that the building’s turbulence affects the wind’s horizontal and vertical direction, as well as its speed, in downstream places. The wall’s effect on wind speed changing in the downstream area is thoroughly investigated. It turns out that while choosing an installation location, disturbing flow areas or low disturbing flow zones should be avoided to have the least impact on wind turbine performance.

Recent advancements in drilling technology have driven substantial progress in cuttings removal tool development, particularly for addressing borehole cleaning challenges in highly deviated directional critical factors in operational safety and efficiency improvement. Despite these innovations, two fundamental challenges persist: an incomplete understanding of mechanistic cuttings removal processes and an insufficient methodological framework for optimal tool installation. Studying the installation positions and assessing the effects of two cuttings removal are essential steps to advance the application of such tools. This investigation was initiated with a comprehensive analysis of particle settling dynamics and migration behaviors in annular wellbore spaces. Building upon Moore's terminal settling velocity equation, a modified model was developed to characterize the transport patterns of cuttings. Through model integration, the precise positioning of the efficient Vortex Cuttings Removal Tool (VCRT) was determined at 188 m from the bit. Subsequently, Computational Fluid Dynamics (CFD) numerical simulation was employed to reveal distinct annular flow field characteristics between VCRT and conventional drilling tools. Field validation in Well Z401X demonstrated a strong correlation between empirical measurements and simulated predictions, with pressure drop deviations of 6.25% and rotational speed variances limited to 7.50%. Analytical results confirmed VCRT's superior performance, exhibited 36.43% reductions in cuttings accumulation at the wellbore's lower quadrant compared to conventional drilling tools. The application of VCRT accelerated cuttings migration velocity in the annular space, significantly increasing the volume of returned onsite cuttings. Friction resistance decreased by approximately 35.90%, indicating higher cuttings removal efficiency than conventional drilling tools.

The ultra-high-frequency (UHF) method is used to analyze the insulation condition of electric equipment by detecting the UHF electromagnetic (EM) waves excited by partial discharge (PD). As part of the UHF detection system, the UHF sensor determines the detection system performance in signal extraction and recognition. In this paper, a UHF antenna sensor with the fractal structure for PD detection in switchgears was designed by means of modeling, simulation and optimization. This sensor, with a flat-plate structure, had two resonance frequencies of 583 MHz and 732 MHz. In the laboratory, four kinds of insulation defect models were positioned in the testing switchgear for typical PD tests. The results show that the sensor could reproduce the electromagnetic waves well. Furthermore, to optimize the installation position of the inner sensor for achieving best detection performance, the precise simulation model of switchgear was developed to study the propagation characteristics of UHF signals in switchgear by finite-difference time-domain (FDTD) method. According to the results of simulation and verification test, the sensor should be positioned at the right side of bottom plate in the front cabinet. This research established the foundation for the further study on the application of UHF technique in switchgear PD online detection.

There is a large number of uncertain harmonic sources and background harmonics in the distribution network. Due to the function of the system node admittance matrix, the installation position of the filter has a significant impact on the harmonic control effect. In this paper, we aim to reduce the current distortion rate of the distribution network and optimize the optimal installation position of the active filter. Based on the principles of harmonic active/reactive power division and the relationship curve between the injection compensation current of each bus and the distortion rate, if the value of the current distortion rate meets the national standard requirements, we can obtain the compensation status of each bus filter for each harmonic and the corresponding compensation current. The bus with the smallest injected compensation current is the optimal installation location of the active filter. Simulation results by Matlab/Simulink verify the feasibility of the method. The results show that on the premise that the distortion rate meets the requirements of grid connection, the capacity of the filter is reduced, and the better economic efficiency is achieved.