Virtual design and performance prediction of a silencing air cleaner used in an I.C.engine intake system

This paper reports results of the authors’ studies on the virtual design method used in the development of low noise intake system of I.C. engine. The resulting high pass-by noise at level above the legislative target at full throttle when engine speed was around 5200 r/min necessitated a BEM-aided redesign task, following the typical process of design and development of an intake system. During the initial design, based on the acoustic theory and the requirements (1. The air flux of the redesigned should equal to or exceed the value of the original flux; 2. The filtering area must not be degraded), and considering the constraint of space in the engine compartment, total volume and rough internal dimensions were determined. During the detailed design, the exact internal dimensions of the air cleaner were determined, and an effective method was applied to improve the acoustic performance at low frequency. The predicted sound power of the intake system indicated that the objective of reducing the overall engine noise by minimizing intake system noise was achieved.

VIRTUAL DESIGN OF A NEW TYPE OF HYDRAULIC SUPPORT

Using virtual reality to design a new type of hydraulic support is discussed.That is how to make use of the virtual design to develop coal mining machine in practice. Theadvantages of virtual design are studied and the simple virtual reality system is built. The 3Dparts and elements of hydraulic support are modeled with parametric design in CAD software, thenexported to VR environment, in which the virtual hydraulic support is assembled, operated andtested. With the method, the errors and faults of design can be fined easily, many improvements aremade and the new hydraulic support is developed successfully.

Modular Fixture Assembly Model for Virtual Assembly Design

To support modular fixture assembly design in virtual environment,a multi-view based modular fixture virtual assembly model is proposed.Instead of squeezing all assembly related information into a single model,three complementary views of assembly model,element information,function and structure,and assembly relationship are proposed to be used.The first view contains the detailed element information,while the other two explicitly capture the hierarchical function relationships and mating relationships respectively.These views are complementary in the sense that each view only contains a specific aspect of assembly related information while together they include required assembly related information.The proposed assembly model is specialized to accommodate the features of modular fixture virtual assembly design and applied in our developed prototype system.

Interactive sculpting of product shape based on constraint manipulation in virtual environment

In product concept design, not only designers with professional CAD skills, but also final customers take part in the design and evaluation of product shape styling. Because customers usually lack surface modelling background and are not familiar with concrete operations of commercial CAD systems, it is difficult for them to express their change intentions of product shape through professional CAD tools if they are not satisfied with the current shape design. This paper puts forward a method for creating, dragging and manipulating constraint and load represented in form of icon entity in interactive sculpting of product shape in virtual environment. The method supports customers manipulation of sculpting constraints or loads on sculpting shapes in virtual reality interaction to control the deformation of product shape. Constraints management based on icon entity is similar to spline lofting operation that is familiar to engineers, so users do not need to know surface details or have any professional knowledge of surface modelling, by only using their physical and engineering experience, they can manipulate the sculpting of product shape intuitively.

Research on virtual dynamic optimization design for NC machine tools

Virtual dynamic optimization design can avoid the repeated process from de-sign to trial-manufacture and test.The designer can analyze and optimize the productstructures in virtual visualization environment.The design cycle is shortened and the costis reduced.The paper analyzed the peculiarity of virtual optimization design,and put for-wards the thought and flow to implement virtual optimization design.The example to opti-mize the internal grinder was studied via establishing precise finite element model,modi-fying the layout of Stiffened Plates and designing parameters of the worktable,and usingthe technology of modal frequency revision and the technology of multiple tuned damper.The result of optimization design compared the new grinder with the original grinder showsthat the entire machine's first orders natural frequency is enhanced by 17%,and the re-sponse displacement of the grinding-head has dropped by 28% under the first order natu-ral frequency and by 41% under second order natural frequency.Finally,the dynamic per-formance of the internal grinder was optimized.

EDUCATIONAL EFFECTIVENESS OF A VIRTUAL DESIGN STUDIO ON ZERO-ENERGY BUILDING DESIGNS:THE CASE OF THE U.S.SOLAR DECATHLON DESIGN CHALLENGE

Ongoing global architectural agendas span climate change,energy,a carbon-neutral society,human comfort,COVID-19,social justice,and sustainability.An architecture studio allows architecture students to learn how to solve complicated environmental issues through integrated thinking and a design process.The U.S.Department of Energy’s Solar Decathlon Design Challenge enables them to broaden their analytic perspectives on numerous subjects and strengthen their integrated thinking of environmental impacts,resilience,sustainability,and well-being.However,the unprecedented impact of the global COVID-19 pandemic transformed the physical studio-based design education system into an online-based learning environment.Mandatory social distancing by the global COVID-19 pandemic restricted interactive discussions and face-to-face collaborations for the integrated zero-energy building design process,which requires features of architecture,engineering,market analysis,durability and resilience,embodied environmental quality,integrated performance,occupant experience,comfort and environmental quality,energy performance,and presentation.This study emphasizes the educational effectiveness of virtual design studios as a part of the discourse on architectural pedagogy of zero-energy building(ZEB)design through integrated designs,technological theories,and analytic skills.The survey results of ten contests show educational achievement with over 90%of the highest positive tendency in the categories of embodied environmental quality and comfort and environmental quality,whereas the positive tendency of educational achievement in the categories of integrated performance,energy performance,and presentation were lower than 70%.The reason for the low percentage of simulation utilization and integrated performance was the lack of a proper understanding of and experience with ZEB simulations and evaluations for undergraduate students.Although VDS is not an ideal pedagogical system for the iterative design critique process,it can support the learning of the value of architectural education,including integrative design thinking,problem-solving skills,numerical simulation techniques,and communicable identities through online discussions and feedback during the COVID-19 pandemic.

Design of virtual machine tool programme technology

this paper overall programme research on virtual design technology of machine tools, not only established a virtual design environment, identify reasonable options in a relatively short period of time, but also providing the basis for quotation, therefore reflecting a favourable measures quickly to market demand.

Prediction for Dynamic Characteristics of Ring-Plate Planetary Indexing Cam Mechanism

This paper is aimed to propose an approach to predict the dynamic characteristics of ring-plate planetary indexing cam mechanism, which is a novel type of indexing mechanism that employs internal planetary transmission structure. Firstly, the geometry and structure of the mechanism are discussed and the kinematic practicability is simulated with virtual prototype design. Then a 3D finite element model of the ring-plate planetary indexing cam mechanism is developed with the commercial software of MATLAB and ANSYS. Through the finite element analysis, the natural frequencies and the corresponding mode shapes are predicted in one motion cycle. On the basis of the virtual prototype design and finite element analysis, an experimental prototype is made and tested to validate the prediction of the dynamic characteristics. The agreement between experimental results and the finite element analysis testifies that the finite element model developed is applicable to the prediction of the dynamic characteristics of this type of mechanism.

Historical Canadian Fortress in the Latest Technology

The paper examines thoroughly how utilizing the latest technology, such as a PC （personal computer）, an iPad, or an iPhone, can entertain many people and allow them to learn about the archaeological findings that have become broadly available through the application of new technology. The paper assesses web usage through the difference in availability and convenience of PC and compact devices by connection to 3D augmented reality applications. Modem technology has allowed access to this information to become radically altered, whereas historical records and remains are dwindling. However, the development of 3D technology means that the general public can experientially pursue the dignity of historical buildings. It also becomes easier through the use of the latest technology to decipher the effectiveness of people＇s interaction with inclusive descriptions of the documentation. This research aims at verifying the visualization of Fort Frontenac by the use of a chronological renovation process. This paper is composed of five elements： an introduction, the historical records about the necessity of 3D modeling, heritage visualization by means of 3D modeling, web design, and iPad and iPhone usage, a comparison of the architectural change that occurred in the

Chronological Restoration of Fort Frontenac in 3D for Heritage Visualization

This paper is composed of three elements： 3D modeling, web design and heritage visualization on the basis of the chronological restoration of Fort Frontenac in 1673, 1675, 1680, 1685 and 1688, changing from narrow and plain to broad, grand features. The aim is to use computer graphic design to inform and create an interest in historical visualization by rebuilding Fort Frontenac using 3D modeling and interactive design. The final model can be integrated into an interactive website to learn more about the fort＇s historic importance. It is apparent that using computer graphics can save time and money when it comes to historical visualization. Visitors do not have to travel to the actual archaeological buildings and can simply use the web in their own homes to learn about this information virtually. In order to create a sophisticated restoration of archaeological buildings, meticulously assessing historical records will draw viewers into the visualizations, such as the historical world of Fort Frontenac. As a result, the completed restoration allows the viewers to effectively understand the fort＇s social system, habits and historical events.

Control of Water Supply in Pipe Networks Nonlinear Case

The paper deals with control of supply in pipe networks based on so-called Dynamic Virtual Distortion Method. Making use of the analytical network model of this installation and using presented below, the so-called Virtual Distortion Method （VDM）, the control of water supply can be performed. Minimization of supply pressure in inlets to the network, subject to inequality constraints imposed on outlet pressure （in chosen nodes） is discussed. Taking advantage of pre-computed influence vectors, the real-time control strategy can be realised with small computational effort and therefore, can be managed with use of hardware-based controllers. Non-linear constitutive relation （water flow vs. pressure head） has been assumed.

Towards digital architecture,engineering,and construction(AEC)industry through virtual design and construction(VDC)and digital twin

The architecture,engineering,and construction(AEC)industry is undergoing a substantial change,and the tech-nological advancements are shaping the future of this industry.Over years,numerous tools have been developed based on building information modeling(BIM)and the Internet of Things(IoT)to manage a variety of tasks and activities within different construction and operational phases in the AEC industry.Recently,with the advent of novel internet-enabled technologies in providing the ability of real-time connectivity,researchers have started to develop virtual design and construction(VDC)and digital twin approaches to remotely monitor,control,and optimize different work progresses and activities in real-time at any work level in the AEC industry.This paper presents a reference model to illustrates the main advantages and applications of VDC and digital twin,and to demonstrate their trends and anticipated cost savings in the AEC industry at a global level.These technological advancements along with augmented reality(AR)and virtual reality(VR)can offer the unique benefit of real-time monitoring of the current status as well as predicting the future of any physical structure at any level of work.The global demand and usage of these technological advancements will lead to great cost savings in the AEC industry which would be US$950 million in design and construction and US$400 million in operation and maintenance phases in the non-residential AEC industry in 2025.This paper also discusses the future challenges of VDC and digital twin in the industry.As a main line of future research,these technologies can simultaneously be utilized with artificial intelligence to enable human-centered decision making to automate and optimize work progresses.Such integrations of VDC,digital twin,artificial intelligence,and human-centered approaches will shape the future of the AEC industry and provide numerous research opportunities in this domain.

Virtual design and analysis with multi-dimension coupling for engineering machinery cooling system

A good cooling circle should ensure that the system can work at an appropriate temperature in the requirements of power increase,engine compartment constraint and working demands for modern engineering machinery,which asks for a thorough understanding of system thermal loads before practical production.However,traditional experiment method spends a long time,costs a huge resource but lacks efficiency,whereas virtual design can avoid the shortcomings of traditional method and can analyze operating states adequately with variable loads on engine,generator,drives,battery pack and HVAC systems.Therefore,this paper focuses on a new virtual design method based on multi-dimension coupled simulation adopting Flowmaster software for initial prediction and CFX tool for further optimization.The simulation results in different operating conditions are compared and validated with experiments.Orthogonal experiment and range analysis are used to explore key parameters of cooling system.The research will be helpful in guiding future design and optimization of engineering machinery.

Designing natural product-like virtual libraries using deep molecule generative models

Natural products（NPs） have long been recognized as a valuable resource for drug discovery, and bringing NP-related features to virtual libraries is believed to be an effective way to increase the coverage of druggable chemical space. Here, deep learning-based molecule generative model, which is a recent technique in de novo molecule design, was applied to generate virtual libraries with NP-like properties. Results demonstrated that the model was effective in generating molecules that highly resemble NPs. Moreover, the model was also found to be capable of generating NP-like molecules that were also easy to synthesize, significantly increasing the practical value of the compound library.