The non-uniform inflow caused by the elbow inlet is one of the main reasons for the low actual operation performance of a centrifugal pump. Orthogonal experiment and GA_PSO algorithm are used to improve the head and efficiency of a centrifugal pump with an elbow inlet based on the method combining numerical simulation and prototype experiment in this paper. The effects of the design parameters, including elbow inlet radius ratio, blade inlet angle, blade number, blade wrap angle, blade outlet angle, impeller outlet diameter, blade outlet width and flow area ratio, on the pump head and efficiency are studied in the orthogonal experiment. The blade inlet angle is the major factor to match the non-uniform inflow and reduce the flow loss in the impeller inlet to contribute to enhancing the pump performance and cavitation characteristics. The particle swarm optimization (PSO) algorithm is optimized by integrating the genetic algorithm (GA), which ensures that the PSO-calculation result avoi... [more]

This article describes the methodology used to identify the mathematical equation that describes the correlations between the input and output parameters of an experiment. As a technological process, aerodynamic separation was chosen to represent the behavior of a solid particle within an ascending vertical airflow. The experimental data were used to identify two parameters, namely the average linear velocity and the angular velocity. The Table Curve 3D program was used to develop a mathematical equation describing the dependence between the input parameters (the shape and size of the solid particle, as well as the velocity of the airflow) and the monitored parameters. A pyramid-type analysis (following a filtering system, a general equation was determined from a large number of equations that characterize an experimental set mathematically) was designed in order to determine a single mathematical equation that describes the correlation between the input variables and those obtained as... [more]

Check valves are used extensively in industrial piping systems. Based on dynamic mesh technology, this study uses the RNG k-ε turbulence model to numerically calculate the dual disc check valve’s three-dimensional transient flow. The dynamic characteristics of the check valve in the pipeline system are also experimentally studied. To this end, the two discs are opened synchronously during the valve-opening process, including four stages: opening discs at a constant angular velocity, opening slowing down discs, slowly returning discs to the balance point, and discs maintaining oscillation. However, the movements of the two discs are asynchronous in the valve-closing process. As the downstream pressure increases, the valve disc begins to close, and the flow gradually stops; reverse flow takes shape, and the reverse flow stops until the discs are fully closed, and slamming of the check valve occurs. The non-dimensional dynamic characteristic curve of this type of dual disc check valve has... [more]

In order to improve the hydraulic performance of the centrifugal prefabricated pumping station and improve its internal flow pattern, this paper optimizes the geometric model of the centrifugal prefabricated pumping station based on the orthogonal optimization method. Through the subjective analysis method and range analysis method, it is concluded that the primary and secondary order affecting the hydraulic performance of the prefabricated pumping station is: center distance Y, pump spacing S, inlet radius R, suspension height Z, inlet height H, and the optimal parameter combination is pump spacing 550 mm (5.5 d), The suspension height is 300 mm (3.0 d), the center distance is 100 mm (1.0 d), the inlet height is 700 mm (7.0 d), and the inlet radius is 75 mm (0.75 d). The orthogonal optimization results show that under the design condition (Qd = 33.93 m3/h), the efficiency of the centrifugal prefabricated pumping station is 64.69%, which is increased by 0.70%, compared with the initial... [more]

Sustainable blank dimension design is the key to the implementation of green industrial development. However, blank dimension design only considers the blank production factor of the blank dimension design stage, which cannot guarantee the blank production stage and the use stage’s overall goal. In this paper, based on the guiding thinking of a business compass, a low-carbon and low-energy consumption blank dimension optimization design model was proposed. Taking the process parameters of the production and the use of the blank as the variables, the grey wolf optimization algorithm was adopted to solve the problem. Taking the gear blanks dimension as an example, the optimized blank dimension is 98.6, compared with the standard blank dimension of 100, 105, the energy consumption is 95.7% and 93.1%, the carbon emission is 92.6% and 90.2%, and the material consumption is 96.5% and 87.5%, respectively. The sustainable blank dimension design has obvious advantages in terms of low energy con... [more]

This paper addresses an effective method for the selection and design of optimal working fluids of organic Rankine cycle (ORC) based on quantitative working fluid selection rules, aiming to reduce the complexity and improve the calculation efficiency of the working fluid design model. In the proposed method, the critical properties of the optimal working fluids for the given heat sources are first explored and summarized based on the quantitative relationship obtained by existing research and simulations. Based on the concept of working fluid substitution, the critical properties of the optimal pure working fluid are then adopted to target the optimal mixture working fluid by solving a modified computer-aided molecular-mixture design (CAMD) model and the ratio r of critical pressure to critical temperature is also strictly constrained to ensure a better working fluid. The component and the composition of the mixture working fluid are, thus, determined simultaneously. Results showed tha... [more]

In this paper, an embedded multichannel capillary porous system (EM-CPS) was designed and fabricated with 304 stainless steel using the laser ablation method. The EM-CPS revealed its excellent ability to wick liquid lithium to its surface effectively. The interaction between Li-prefilled EM-CPS and plasma was studied, and the results showed that the surface temperature decreased by ~140 °C compared with the results of the experiment of EM-CPS without lithium filling. Additionally, EM-CPS displayed a better heat transfer performance and stronger radiation loss of the vapor cloud than the traditional woven tungsten-based meshes. In addition, the drift of the lithium vapor cloud center was found during plasma irradiation and led to a decrease in the intensity of the Li 670.78 nm emission line detected by the spectrometer at the observation point. When the thermal load deposited on the sample surface is reinforced by increasing the magnetic field, the rise in surface temperature is restrai... [more]

Improving the performance of flame holders has been a key focus of research on ramjet combustors. The plasma actuator has the potential to improve the ignition performance by manipulating the flow field of the flame holder. In this study, a plasma-actuated flame holder was designed. The aim of this study is to improve the performance of ramjet combustor by applying plasma discharge to the flame holder. The aerodynamic effects and ignition performance of the flame holder were investigated. The results demonstrated that the induced jet direction of the surface arc discharge was perpendicular to the actuator. The induced jet dissipated faster at lower pressures. The aerodynamic actuation intensity and jet area increased with the number of channels of surface arc discharges. Increasing discharge frequencies can increase the discharge times and jet height. The aerodynamic effects under a microsecond pulse duration were better than those under a nanosecond pulse duration. Actuators installed... [more]

The MDAO framework has become an essential part of almost all fields, apart from mechanical, transportation, and aerospace industries, for efficient energy conversion or otherwise. It enables rapid iterative interaction among several engineering disciplines at various fidelities using automation tools for design improvement. An advanced framework from low to high fidelity is developed for ducted and unducted turbomachinery blade designs. The parametric blade geometry tool is a key feature which converts low-fidelity results into 3D blade shapes and can readily be used in high-fidelity multidisciplinary simulations as part of an optimization cycle. The geometry generator and physics solvers are connected to DAKOTA, an open-source optimizer with parallel computation capability. The entire cycle is automated and new design iterations are generated with input parameter variations controlled by DAKOTA. Single- and multi-objective genetic algorithm and gradient method-based optimization case... [more]

Water pollution is a severe health concern. Several studies have recently demonstrated the efficacy of various approaches for treating wastewater from anthropogenic activities. Wastewater treatment is an artificial procedure that removes contaminants and impurities from wastewater or sewage before discharging the effluent back into the environment. It can also be recycled by being further treated or polished to provide safe quality water for use, such as potable water. Municipal and industrial wastewater treatment systems are designed to create effluent discharged to the surrounding environments and must comply with various authorities’ environmental discharge quality rules. An effective, low-cost, environmentally friendly, and long-term wastewater treatment system is critical to protecting our unique and finite water supplies. Moreover, this paper discusses water pollution classification and the three traditional treatment methods of precipitation/encapsulation, adsorption, and membra... [more]

The construction machinery and vehicles, especially the explosion-proof and explosion-isolation ability of the vehicles are playing an increasingly important role in the complex and unpredictable emergency rescue field. In this paper, the explosion-proof housing of hydraulic system power unit applied in engineering machinery is investigated, wherein the power unit includes motor, power supply and control element. Motor-driven hydraulic pump provides the necessary power for the hydraulic system. The gas explosion process, basic parameters, flame acceleration mechanism and the theory model of gas explosion in finite space are analyzed. Relevant mathematical models of the experimental gas explosion for explosion-proof cavity are established. Furthermore, the models are analyzed by numerical method. We simulate the dynamic process of explosion by software. The analysis, examination and simulation of structural strength are conducted on the explosion-proof cavity according to the maximum ex... [more]

Modeling is the primary point to conveying product characteristics. Accurately capturing the image needs of users for modeling is an important way to effectively improve product design efficiency. Quantitative theory type I is a method to solve the internal law between the user’s target image and the product modeling characteristics by building a mathematical model. Aiming at the problems of abundant product modeling design elements, diversified combination methods, and high design cost due to the subjective ambiguity of user images, a topological design method of product modeling based on quantification theory I is proposed. This method uses the semantic difference method and statistical method to obtain the quantitative data of perceptual semantic features of product modeling to represent the explicit and implicit needs of users. Based on the topological transformation, the topological analysis and modeling of the two types of requirements are carried out. The mapping model of produc... [more]

A new type of dishwasher pump without a pipeline system was invented for the first time to form an original sink-type dishwasher avoiding the accumulation of dirt in the hydraulic system. In order to improve the hydraulic performance of this new type of dishwasher pump with twin-volute passive rotation driven by a compound impeller, an orthogonal optimal design method was first introduced to optimize the compound impeller composed of axial cascades and radial blades. Six geometric parameters were selected as the main factors to design the orthogonal table L18(36). All impeller models were manufactured via high-precision 3D printing and tested to determine the optimal solution. Firstly, the hydraulic performance was measured using a specially designed test bench under the assumption of static-volute conditions. Then, the optimization scheme was verified in real machine experiments under the rotating-volute condition, and numerical calculations were used to assess the performance improve... [more]

This paper presents a descriptor representation-based guaranteed cost design methodology for polynomial fuzzy systems. This methodology applies the descriptor representation for presenting the closed-loop system of the polynomial fuzzy model with a parallel distributed compensation (PDC) based fuzzy controller. By the utility of descriptor representation, the guaranteed cost control (GCC) design analysis can utilize polynomial fuzzy slack matrices for obtaining less conservative results. The proposed GCC design is presented as the sum-of-squares (SOS) conditions. The application of polynomial fuzzy slack matrices leads to the double fuzzy summation issue in the control design. Accordingly, the copositive relaxation works out the problem well and is adopted in the control design analysis. The GCC design minimizes the upper limit of a predesignated cost function. According to the performance function, two simulation examples are provided to demonstrate the validity of the proposed GCC de... [more]

Exploring new solvents for efficient acid gas removal is one of the most attractive topics in industrial gas purification. Herein, using 2-tertiarybutylamino-2-ethoxyethanol as an absorbent in a packed column at atmospheric pressure was examined for selective absorption of H2S from mixed gas streams. In the present work, the acid gas load, H2S absorption selectivity, acid gas removal ratio, amine solution regeneration performance, and corrosion performance were investigated through evaluating experiments absorbing H2S and CO2 by using methyldiethanolamine and 2-tertiarybutylamino-2-ethoxyethanol. The experimental results illustrate that the H2S absorption selective factors were 3.88 and 15.81 by using 40% methyldiethanolamine and 40% 2-tertiarybutylamino-2-ethoxyethanol at 40 °C, respectively, showing that 2-tertiarybutylamino-2-ethoxyethanol is an efficient solvent for selective H2S removal, even better than methyldiethanolamine. Based on the consideration of cost, we added 5% TBEE to... [more]

Extractive distillation with salts, unlike other dehydration technologies, is better due to the null toxicity that exists in the distillate, since salt cannot be evaporated. With this distillation technology, it is possible to obtain a high concentration of ethanol, however, there are still problems in the control of the distillation columns in the presence of disturbances. The present work deals with the simulation and control of an extractive distillation column using CaCl2 as a separating agent, for which the Aspen Dynamics® simulator is used. The measurement and control of the ethanol composition are carried out by means of temperature, in addition, four control structures are evaluated and compared. These structures are L, D, LV, and DV, which are the most common in conventional distillation, and their performance is measured by means of deterministic indicators applying changes (disturbances) of composition and the flow rate in the main feed of the column. The most relevant resul... [more]

The demand for new novel flavour and fragrance (F&F) molecules has boosted the need for a systematic approach to designing fragrance molecules. However, the F&F-related industry still relies heavily on experimental approaches or on existing databases without considering the consequences resulting from changes in concentration, which could omit potential fragrances. Computer-aided molecular design (CAMD) has great potential to identify novel molecular structures to be used as fragrances. Using CAMD for this purpose requires models to predict the olfaction properties of molecules. A rough set-based machine learning (RSML) approach is used to develop an interpretable predictive model for odour characteristics in this work. New rule-based models are generated from RSML based on the dilution and a number of different topological indices which identify the structure-odour relationship of fragrance molecules. The most prominent rules are selected and formulated as constraints in a CAMD optimi... [more]

This article offers a general approach to studying a four-bar mechanism from a geometric viewpoint. The four-bar mechanism form is used in a large number of existing pieces of machinery and equipment. This type of mechanism, used to drive a screen and generate its oscillating motion, is referred to in this article for its application in separation systems. In the literature, there are numerous approaches for analyzing such a mechanism. In addition to determining this mechanism’s geometry, an examination of the influence of the drive system’s position on the motion of the tie rods, or the support system of an oscillating site, is also conducted. In the investigation, the connecting rod angle was adjusted between −45 degrees and 60 degrees without respect to the horizontal. The following parameters, which correspond to the operation of the oscillating sieve motion, were obtained from the determined mathematical relations: the movement made by the free end of the tie rod; the tie rod’s an... [more]

To improve the seeding qualification rate and stability of the air-suction vibrating disc type seed meter on the rice seedling raising line, in this paper, an improved wireless sensor network node layout optimization algorithm was proposed, and the operation monitoring system of the seed meter was designed using the Internet of Things and configuration software. In the system, the upper computer software adopted the Kingview software, the lower computer took the STM32F429IGT and CC2530 as the core controllers, and ZigBee was selected for data transmission to build the wireless sensor network. The acquisition of field status information and the sending of control instructions were realized through the sensor nodes constructed by the CC2530 core controller. The data was sent to the coordinator node in real-time through the wireless sensor network. The coordinator node realized the bidirectional transmission of data with Kingview and the upper computer control instructions forwarding usin... [more]

This research studies the discharge process and its mechanism using the discrete element method (DEM) with self-developed annular corrosion pill particles and the discharge device as an example in order to optimize the oil and gas field wellbore casing annular corrosion process. The object of study was chosen from four different grid numbers and four different grid widths, and EDEM software was utilized to simulate and assess the pill particle discharge process based on preliminary experimental research. Under five different pill wheel rotation speeds, the effects of the grid number and grid width on the filling amount, filling density, discharge variation coefficient, and compressive force of pill particles were investigated from macroscopic and microscopic viewpoints. The findings reveal that the grid number, grid width, and rotation speed all have a significant impact on pill filling and discharge performance. As a result, the discharge wheel’s structure and operating characteristic... [more]

Researching the moving speed of particles in a drum is helpful to the optimal design of the rotating device. In this paper, the average mixing velocity of flake particles with different shapes in an elliptical drum is studied. In detail, the mixing systems of rectangular, triangular, and circular flake particles and circular particles are studied; the rollers with different eccentricities are studied; the velocity and periodic variation characteristics of the particle system at 15 rpm and 45 rpm are compared and analyzed; the variation curves of particle average velocity, velocity peak fitting curve (PFC), velocity trough fitting curve (TFC), and velocity fitting under various working conditions are drawn. The results show that the average velocity fluctuation range of the particle system increases gradually with the increase of the eccentricity of the rotating device and the volume of flake particles; the fluctuation of particle average velocity fitting curve and PFC curve in the elli... [more]

This paper examines a novel approach to activated carbon (AC) production that uses pea waste (PW) and to what extent it is economically competitive with current production methods. Additionally, the outcome is to provide a detailed economic analysis to understand whether this process is viable. The focus of this production route and the economic analysis will be on a United Kingdom (UK) basis. The plant will be located within the north UK to minimise storage and transportation costs. It also has extensive links to other clusters of nearby industries that would produce from this process in air pollution control or wastewater treatments. The overall production process is detailed, and detailed equipment specifications, including the sizing of equipment and utility requirements, were also given. Material balance calculations are carried out to assess the performance and improve process design. An economic analysis is performed to study the potential of biomass-to-AC conversion costs and c... [more]

The full tubular pump device is taken as the research object in this article. This research method adopts the numerical simulation technology based on the SST (Shear-Stress-Transport) k-ω turbulence model to explore the internal flow characteristics of the stator−rotor cavity of the full tubular pump and optimize the stator−rotor clearance structure. The research shows that under the design conditions, compared with the axial flow pump, the torque increases by 47.91 N·m at the stator−rotor cavity structure and the efficiency decreases by about 20%. The torque at the rotor clearance of the full tubular pump accounts for about 50% of the torque at the rotor. Since there is a large area of backflow on both sides of the cavity, and there is a vortex structure on the inlet side of the cavity, it shows that the rotor structure and its area greatly affect the operating efficiency of the pump device. With the reduction in the rotor force area, the clearance length, and the outer diameter of th... [more]

This paper examines the simulation, design, and fabrication of a nano-particle silver microheater. COMSOL Multiphysics is used to simulate the microheater of an area of 720 × 720 μm2. Different stages of the microheater fabrication process are discussed. The size of the cartridge used is 10 pL and the nozzle diameter was 50 μm. The drop spacing was chosen to be 45 μm after testing several different values. Controlled printing of Ag ink was reached by setting the tickle control frequency to 8 kHz and cartridge print height to 0.4 mm. The nozzle temperature was set at ambient temperature. The inkjet printed microheater is of same area and track and gap widths of 110 μm. The measured resistance of the microheater, 119 Ω, is approximately equal to the simulated resistance of 100 Ω. It was observed that the temperature at the center of the heater reaches up to 250 °C.

Petroleum-based plastics have become a big problem in many countries because of their non-degradability and that they become microplastics in the environment. This study focused on the optimization of production medium and conditions of polyhydroxyalkanoates (PHAs), which are biodegradable bioplastics and are accumulated in microbial cells. Among 341 isolates from 40 composted soil samples, the best isolate was the HD34 strain, which was identified using morphological, molecular, and biochemical methods. The results showed that the strain was most closely related to Ensifer adhaerens LMG20216T, with 99.6% similarity. For optimization of production medium and conditions using response surface methodology, it exhibited an optimal medium containing 3.99% (w/v) of potato dextrose broth (PDB) and 1.54% (w/v) of D-glucose with an adjusted initial pH of 9.0. The optimum production was achieved under culture conditions of a temperature of 28 °C, inoculum size of 2.5% (v/v), and a shaking speed... [more]