Advanced Simulation Software Research Articles

Underwater explosive bubble interaction with an adjacent submerged structure

An experimental and computational investigation was conducted to study the interaction between bubbles generated by an underwater explosive (UNDEX) and a nearby steel plate structure. The experiments were performed for different standoff distances to investigate the interaction between the gas bubble and the rigid structure. High-speed photography was utilized to capture the underwater explosive gas bubble’s behavior, and a series of pressure transducers were used to record the emitted pressure histories. The numerical simulations were performed with the Dynamic System Mechanics Advanced Simulation software, which is a full y coupled Eulerian–Lagrangian fluid–structure interaction code. The numerical simulations were validated with the experiments in terms of the detonation pressure, structural surface pressures, and UNDEX gas bubble growth and collapse. Results show that the UNDEX standoff distance greatly influences the gas bubble’s shape, migration speed, bubble jetting behavior, and loading into its adjacent structure. Moreover, the impulse generated by the shock wave on the plate surface proved to be small in comparison to the impulse generated by the collapse of the UNDEX gas bubble. The magnitude of impulse depends on standoff distance, collapse symmetry, and relative collapse location.

Numerical Simulation of Fluid Carrying Pollutant Particles Erosion in Elbow Pipe Is Carried out by COMSOL

With the development of Marine energy to the deep and ultra-deep-water field, the severe environment of high temperature and high pressure in the engineering background makes the problem of flow security in oil and gas transportation system more serious and prominent. For this part of the underwater production and processing system, more stringent requirements are put forward. In order to study the erosion of fluid pipelines such as oil and natural gas, the COMSOL (A large-scale advanced numerical simulation software) finite element model was used. Under the condition of different flow parameters, the erosion trajectory of solid particles in the pipeline and the erosion failure rule of the bend are obtained. In this paper, the erosion wear rate of 90° pipe elbow is calculated, and three different erosion models are compared.

P‐169: Towards Fully Integrated 3D Master Equation — Kinetic Monte Carlo Predictive Device Simulations

In the past decade, the discovery of organic semiconductor materials and the development of organic electronic devices has occurred mostly by experimental trial‐and‐error. In the past years, rational design based on predictive modeling has started playing a larger role in accelerating research and development of organic semiconductor devices. To make this transition possible, we developed and validated advanced predictive simulation software, Bumblebee, based on 3D kinetic Monte Carlo (KMC) and 3D master equation (ME) methods for simulating state‐of‐the art multilayer organic light emitting diode (OLED) stacks. While the 3D‐KMC engine is optimized for high voltages, the 3D‐ME engine is especially suitable for the low voltage regime, making these two engines complementary to each other for efficient simulation of OLED device performance in different operation regimes. To demonstrate the power of predictive modelling, we show several examples of device simulation results obtained with Bumblebee for different OLED stacks. Particular focus will be given to the low current/low voltage range where the impact of traps and energetic disorder on device turn‐on/turn‐off is most important.

Semi-Implicit and Semi-Explicit Adams-Bashforth-Moulton Methods

Multistep integration methods are widespread in the simulation of high-dimensional dynamical systems due to their low computational costs. However, the stability of these methods decreases with the increase of the accuracy order, so there is a known room for improvement. One of the possible ways to increase stability is implicit integration, but it consequently leads to sufficient growth in computational costs. Recently, the development of semi-implicit techniques achieved great success in the construction of highly efficient single-step ordinary differential equations (ODE) solvers. Thus, the development of multistep semi-implicit integration methods is of interest. In this paper, we propose the simple solution to increase the numerical efficiency of Adams-Bashforth-Moulton predictor-corrector methods using semi-implicit integration. We present a general description of the proposed methods and explicitly show the superiority of ODE solvers based on semi-implicit predictor-corrector methods over their explicit and implicit counterparts. To validate this, performance plots are given for simulation of the van der Pol oscillator and the Rossler chaotic system with fixed and variable stepsize. The obtained results can be applied in the development of advanced simulation software.

Improving Safety and Traffic Conditions on National Roads Passing through Towns without Bypass

Traffic congestion spread beyond major cities and expands on national roads that connect various sites of interest. Many of these roads pass through the towns whose inhabitants must endure the negative consequences of transit traffic: increased delays and pollution levels, decreasing pedestrians safety. Thus, it is necessary to find a balance between road users’ wishes (drivers and pedestrians) in order to reduce vehicles transit time and increased pedestrians safety. The study of road traffic is a complex problem, difficult to analyze by analytical methods and therefore it is suitable for computer simulation. Using advanced simulation software, the paper investigate the influence of traffic intensity, pedestrian crossings, traffic signals timing and traffic signals coordination parameters through microsimulation of traffic on an important national road that transit a Romanian town without bypass. The proposed solutions can lead to reduced vehicles transit time, of air pollution and an increase of pedestrians safety.

Wind turbine control: open-source software for control education, standardization and compilation

Standardized, easy to use, and preferably open-source research software is an important aspect in supporting and solidifying the wind turbine community. To this end, three contributions in the form of open-source software projects are presented in this paper. First, a community-driven wind turbine baseline controller, the Delft Research Controller (DRC), is presented. The DRC is applicable to high-fidelity simulation software that uses the DISCON controller interface. The controller distinguishes itself by the variety of available control and estimation implementations, its ease of use, and the universal applicability to wind turbine models. Secondly, in the wake of the DRC, the SimulinkDRC graphical controller design and compilation environment has been developed. Users having access to Simulink can benefit from the convenient way of controller development the tool provides. Finally, the FASTTool has been developed for educational purposes, by focusing on the graphical aspect of wind turbine (controller) design. The tool simplifies interaction with the advanced FAST simulation software, by comprehensive visualizations and analysis tools. This paper demonstrates and describes the functionality of all three software projects.

Optimization and Analysis of Structure about Lifting Device of Logistics Sorting

The lifting device of a logistics sorting machine needs high frequency upward and downward reciprocating motion therefore the cutting fork arms and matching parts of the shaft are often worn out. In this paper the problem of the shear fork types applied for the lifting mechanism is studied at first. Then the advanced numerical simulation software ANSYS adopted for the lifting mechanism of the shear fork type, and the means of virtual simulation is introduced. Hence the possible location of faults and fault modes are analysed. Then improving measures about the lifting mechanism of the logistics sorting machine are suggested.

Optimization and Analysis of Structure about Lifting Device of Logistics Sorting

The lifting device of a logistics sorting machine needs high frequency upward and downward reciprocating motion therefore the cutting fork arms and matching parts of the shaft are often worn out. In this paper the problem of the shear fork types applied for the lifting mechanism is studied at first. Then the advanced numerical simulation software ANSYS adopted for the lifting mechanism of the shear fork type, and the means of virtual simulation is introduced. Hence the possible location of faults and fault modes are analysed. Then improving measures about the lifting mechanism of the logistics sorting machine are suggested.

ParallelEye-CS: A New Dataset of Synthetic Images for Testing the Visual Intelligence of Intelligent Vehicles

Virtual simulation testing is becoming indispensable for the intelligence testing of intelligent vehicles. However, even the most advanced simulation software provides rather limited test conditions. In the long run, intelligent vehicles are expected to work at SAE (Society of Automotive Engineers) level 4 or level 5. Researchers should make full use of virtual simulation scenarios to test the visual intelligence algorithms of intelligent vehicles under various imaging conditions. In this paper, we create realistic artificial scenes to simulate the self-driving scenarios, and collect a dataset of synthetic images from the virtual driving scenes, named “ParallelEye-CS”. In the artificial scenes, we can flexibly change environmental conditions and automatically acquire accurate and diverse ground-truth labels. As a result, ParallelEye-CS has six ground-truth labels and includes twenty types of tests, which are divided into normal, environmental, and difficult tasks. Furthermore, we utilize ParallelEye-CS in combination with other publicly available datasets to conduct experiments for visual object detection. The experimental results indicate that: 1) object detection algorithms of intelligent vehicles can be tested under various scenario challenges; 2) mixed dataset can improve the accuracy of object detection algorithms, but domain shift is a serious issue worthy of attention.

Drive simulation tests for electric drilling rig

AbstractThe article presents methodology and selected results of simulation tests of diesel and electric dive system for drilling rig. Research in this field were conducted under the project no. POIR.01.01.01-00-D011/16 entitled „New generation of modular rigs, drilling and bolting, with battery drives, designated to work in underground cooper ore and raw rock material mines”. The project is funded by the National Center of Research and Development (NCBiR). The aim of the project is to design and implementation of innovation drilling and bolting rig with electric drive system. Due to the complexity of the structure of the drive system (mechanical, hydraulic and electrical elements), it was necessary to use advanced simulation software dedicated to multiphysics analysis. Data presented in the article can be used as guidelines in design process of drilling and bolting rigs as well as in optimization their driving system and mechanical construction.

Bank Buildings, Belfast, UK: making safe after a fire

In August 2018, a fire badly damaged a listed building in the centre of Belfast. This left the perimeter walls standing and the inside largely destroyed. Because of the dangerous nature of the structure, the surrounding area was closed. This paper describes the engineering aspects of the approach to making the remaining structure safe to allow the surrounding area to reopen and to start the rebuilding works on the retained building. The design approach to the public safety cordon involved the use of empirical techniques, as well as advanced simulation software. The design approach for the facade-retention scheme was complicated by the poor ground and buried services, as well as having to allow for installation with no access inside the building. The solution involved the use of shipping containers as structural components, as well as fibre-reinforced foundation rafts. The scheme has been successfully installed, and access to the city centre has been reinstated.

Digitally Designed Airport Terminal Using Wind Performance Analysis

Over the past few decades, digital tools have become indispensable in the field of architecture. The complex design tasks that make up architectural design methods benefit from utilizing advanced simulation software and, consequently, design solutions have become more nature-adapted and site-specific. Computer simulations and performance-oriented design enable us to address global challenges, such as climate change, in the preliminary conceptual design phase. In this paper, an innovative architectural design method is introduced. This method consists of the following: (1) an analysis of the local microclimate, specifically the wind situation; (2) the parametric shape generation of the airport terminal incorporating wind as a form-finding factor; (3) Computational Fluid Dynamics (CFD) analysis; and (4) wind-performance studies of various shapes and designs. A combination of programs, such as Rhinoceros (Rhino), and open-source plug-ins, such as Grasshopper and Swift, along with the post-processing software Paraview, are utilized for the wind-performance evaluation of a case study airport terminal in Reykjavik, Iceland. The objective of this wind-performance evaluation is to enhance the local wind situation and, by employing the proposed architectural shape, to regulate the wind pattern to find the optimal wind flow around the designed building. By utilizing the aforementioned software, or other open-source software, the proposed method can be easily integrated into regular architectural practice.

A detailed analysis of free vibration on 70 MW hydro power turbine rotor

Most prime movers have vibrational problems due to the inherent unbalance due to some reason or other, the mass centre of the rotor does not coincide with the geometrical axis of the shaft known as eccentricity. During the shaft rotation a small eccentricity gives rise to a transverse force that increases with shaft rpm and tends to higher deflections of the shaft. In this approach a specified 70 MW hydro power turbine shaft is selected, models are prepared with the beam, mass, and combination elements in advanced engineering simulation software ANSYS for the specified design parameters and dimensions of the turbine shaft for free vibration analysis. The turbine rotor is placed at different locations from left to right of the turbine shaft for different bearing supports using subspace modes extraction method and modes extracted up to critical speed of 3000 rpm, which is the operating speed of the turbine. The results which include the Eigen values, Eigen vectors and responses of free vibrations and used bearing properties are recorded. Finally, it was concluded that there exists a safe location of the turbine rotor on the turbine shaft for each of the different bearing properties.

Acceleration slip regulation control strategy for four‐wheel independent drive electric vehicles

AbstractTo prevent four‐wheel independent drive electric vehicle (4WID EV) wheels from slipping when they are accelerating, an acceleration slip regulation (ASR) control strategy is proposed. Based on the classification of road conditions and the calculation of the optimal slip ratio for road conditions, the slip ratio is adjusted around the optimal slip ratio through controlling the driving torque output. Meanwhile, considering the change of wheel longitudinal force actually, we design a compensator in the ASR control strategy. Then, the system stability is analytically investigated through the classical control theory. Finally, we design an ASR control system in Matlab/Simulink, and apply the advanced simulation software Carsim to build a 4WID EV model, then build a cosimulation model using Carsim and Matlab/Simulink. The simulation results show the effectiveness and validation of the proposed ASR control strategy. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Integrated Daylighting Design by Combining Passive Method with DaySim in a Classroom

This paper suggests a daylighting design method by combining a passive approach and advanced software to design external shading devices for daylighting in a classroom. A simplified method to predict and assess the indoor natural illuminance is a prerequisite for designers to design schools with better performance. Recently there has been growing demand for school refurbishment; mainly environmental improvement of classrooms in Korea. However, the passive approach of design has been neglected while the use of advanced simulation software has increased, requiring additional time and cost. Combining passive design methods with up-to-date numerical simulation is explored with shading devices to verify the daylighting distribution and daylight autonomy in classrooms with different orientations and shading forms. Weather tool Autodesk Ecotect, for the shading coefficient, and DaySim software (v3.0), for daylight autonomy, were adopted for the initial and the detail design stage, respectively. The findings support the linked design approaches of passive and advanced software would benefit designers in the strategic design process with further potential for design options and lighting electricity reduction.

Prediction of SOC of lead-acid battery in pure electric vehicle based on BSA-RELM

The state of charge (SOC) of lead-acid batteries plays an important role in battery management systems. Aiming at the problem that the SOC of lead-acid batteries in pure electric vehicles cannot be measured directly, a novel algorithm based on a robust extreme learning machine (RELM) optimized by the bird swarm algorithm (BSA) is proposed in this paper. RELM overcomes the shortcoming that an extreme learning machine (ELM) cannot deal with outliers and improves the prediction accuracy of ELM. BSA is used to optimize the numbers of hidden layer nodes and the adjustment factors of RELM. The problem that the numbers of the hidden layer nodes and the adjustment factor are difficult to determine is solved, which can further improve the convergence speed of RELM and help to find the global optimal value. The main parameters which affect the SOC of batteries such as current, voltage, temperature, and internal resistance have been collected by the advanced vehicle simulation software ADVISOR to model and test. Simulation results show that compared to other algorithms such as back propagation neural network, radical basis function neural network, and fuzzy neural network, BSA-RELM has a higher prediction accuracy.

Renewable Energy: A Globally Local Issue, States CGtech

The generation of energy and the potentially harmful effects of the by-products created during its generation and end use are a concern to us all. Here, Tony Shrewsbury, managing director of CGTech, highlights how the company’s advanced CNC simulation and optimisation software is playing a key role in improving the bigger picture

The Compliance to Broadcast Standards of a Side-Mounted Circularly Polarized Antenna

Non-directional antenna bays in FM broadcast applications were designed to exhibit radiation characteristics that conform to broadcast standards. However, the metallic tower where these antennas are mounted and secured is not considered during the development process. Knowing that the radiation characteristics of antennas are affected by the metallic tower, it is the aim of this paper to present the compliance of the side-mounted Circularly Polarized Antenna (CPA) to broadcast standards. The CPA compliance to requirements on polarization components, pattern circularity and bandwidth is specifically presented. Results of numerical analyses using an advanced antenna simulation software show that the radiation characteristics of the CPA are severely altered by the presence of the tower and thus impairing its capacity to adhere to the said broadcast requirements. Some adjustments on the CPA structure are needed to improve its performance.

Casting of adjuster bracket—process optimization and validation

ABSTRACTCasting of metal products consists of a series of intricate manufacturing processes that need to be precisely conducted and controlled. Rather than doing process design by a hit-and-trial approach, simulations can be run before casting is actually undertaken in a foundry. These simulations allow to model, verify, and validate the entire casting process along with the prediction of possible defects in the cast products. This study is based on casting an adjuster bracket using traditional mold design approach, and also using simulation. A Computer-Aided Design (CAD) model of the casting is developed in SOLIDWORKS and simulated using MAGMASoft. The results obtained are temperature profile within the mold after pouring, solidification sequence, and casting defects such as porosity and hotspots. Good correlation between experimental and simulation results confirmed sufficient model health to virtually optimize the mold through simulations. The optimized mold design completely removed the hotspot and reduced porosity which is within the machining allowance of the final product. However, the casting yield is reduced by 6% by adding a carefully selected riser in the optimized mold design. It can be concluded that simulations are reasonably accurate in modeling casting process, predicting defects, and modifying casting design using optimization techniques available in the advanced casting simulation software.

Model reduction and model predictive control of energy-efficient buildings for electrical heating load shifting

In France, buildings account for a significant portion of the electricity consumption (around 68%), due to an important use of electrical heating systems. This results in high peak load in winter and causes tensions on the production-consumption balance. In view of reducing such fluctuations, advanced control systems (including the Model Predictive Control framework) have been developed to shift heating load while maintaining indoor comfort and taking advantage of the building thermal mass. In this paper, a framework for developing optimisation-based control strategies to shift the heating load in buildings is introduced. The balanced truncation method and a time-continuous optimisation method were used to develop a real-time control of the heating power. These two methods are well suited for control problems and yield precise results. The novelty of the approach is to use reduced models derived from advanced building simulation software. A simulation case study demonstrates the controller performance in the synthesis of a predictive model-based optimal energy management strategy for a single-zone test building of the “INCAS” platform built in Le Bourget-du-Lac, France, by the National Solar Energy Institute (INES). The controller exhibits excellent performance, reaching between 6 and 13% cost reduction, and can easily be applied in real-time.