Conceptual Engineering Design Research Articles

Thermal and stress analyses of a novel coated steam dual pipe system for use in advanced ultra-supercritical power plant

Improving the energy efficiency of advanced ultra-supercritical power plants, by increasing steam operating temperature up to 700 °C, can be achieved, at reduced cost, by using novel engineering design concepts, such as coated steam pipe systems manufactured from high temperature materials commonly used in current operational power plants. This paper describes a preliminary feasibility analysis of the design concept of a novel coated dual pipe system under steady-state operation, using analytical and finite element models to evaluate the possible thermal gradients and stresses generated. The results show that the protective coating layer contributes to the effective reduction in the surface temperature of the primary steel pipe. Thermal stresses generated due to the significant difference in the thermal and mechanical properties of the coating and substrate pipe are larger than the mechanical stresses generated by the combined effects of the internal steam pressure in the primary steam pipe and external pressure from the counter-flow cooling steam during steady-state operation. Compared with the stress relaxation of the coating and substrate pipe, creep has a significant impact on the stress distribution within the coating layer. Several key factors have been identified, such as the coating thickness, conductivity, thermal expansion, heat transfer coefficient of cooling steam, cooling steam temperature and cooling steam pressure, which are found to govern thermal and stress distributions during steady-state operation.

A MATLAB App to Introduce Chemical Engineering Design Concepts to Engineering Freshmen through a Pharmaceutical Dosing Case Study

An interactive MATLAB simulation app and design project are described for introducing chemical engineering concepts to engineering freshmen. A MATLAB simulation for pharmaceutical drug dosing is packaged with a graphical user interface in an app that is student friendly. Minimal engineering or coding knowledge is necessary to operate and understand the application. The students design drug dosage and frequency of ACE inhibitors for different patient conditions. Teaching tips and frequently asked questions are presented here.

An approach for teaching process safety risk engineering and management control concepts using AIChE's web‐based concept warehouse

One of many efforts to help instructors teach process safety‐related concepts to undergraduate chemical engineers includes using AIChE's web‐based Concept Warehouse, a real‐time, interactive teaching tool which can be used during lectures when teaching chemical engineering subjects. This article describes a student outreach effort by the AIChE Safety and Health Division to help populate the Concept Warehouse with vetted process safety‐related problems. The purpose of this article is to describe how we are bridging the gap between the practitioner volunteering their expertise and faculty members interested in incorporating current process safety‐related concepts into their classes. The goal for this effort is to provide a comprehensive instructional tool that can be used to help teach process safety‐related engineering design concepts, as well as to help teach the essential administrative process safety and risk management system concepts, using problems that describe both the engineering and administrative controls required for safe and reliable operations.The Concept Warehouse is an information database and instructional tool accessible to anyone teaching core chemical engineering topics such as thermodynamics, kinetics, or process safety anywhere in the world. This article defines and provides the framework of this effort to populate the Concept Warehouse with process safety‐related problems. As process safety risk reduction efforts continue to evolve, this article provides updates to traditional definitions that can be used to help orient those unfamiliar with these systems‐related process safety risk management strategies. The article concludes with a few example problems which could be used when teaching process safety‐related concepts. © 2018 American Institute of Chemical Engineers Process Saf Prog 38: e12010, 2019

Are you better off alone? Mitigating the underperformance of engineering teams during conceptual design through adaptive process management

Teams are a major feature of engineering and are commonly thought to be necessary when solving dynamic and complex problems. Even though teams collectively provide a diversity of knowledge, skills, and perspectives to problem-solving, previous work has demonstrated that in certain scenarios, such as in language-based and more spatially oriented configuration design problems, the production by a team is inferior to that of a similar number of individuals working independently (i.e., nominal team). This research explores this comparison of individual versus group problem-solving within the domain of conceptual engineering design. Thus, a behavioral study was run with freshman engineering students, who solved a conceptual engineering design problem individually or collaboratively in a team. Results corroborate previous findings, exhibiting that individuals outperform teams in the overall quality of their design solutions, even within this more free-flowing and explorative setting of conceptual design. Exploiting this result, this work further considers whether adaptive feedback from a process manager can lessen the underperformance of collaborative design teams compared to individuals, by helping teams overcome potential deterrents that may be contributing to their inferior performance. Teams that are under the guidance of a process manager end up performing better than teams that are not in terms of solution quality, and almost as well as individuals, though not significantly different. This result suggests that process managers are able to mitigate some of the deficiencies in design teams. In an attempt to uncover some of the cognitive rationale and strategies that may be beneficial throughout problem-solving, the managerial interactions with the design teams are then investigated. Furthermore, to determine the reason of the collaborative teams’ underperformance, the effect of verbalization is studied as a possible cognitive hindrance. In the end, this work expands growing research on team problem-solving in engineering, and suggests that collaborative teams may not be optimal in every circumstance, but under the proper process management, can become substantially more effective.

The multi-attribute topological graph method and its application on power flow analysis in closed planetary gear trains

The concept of multi-attribute topological graph is proposed in this article to represent the characteristics of both structure and state for typical one-degree-of-freedom planar spur closed planetary gear trains. This method is well applied in power flow analysis and provides a graphical view for the types, values, directions, and transmission relationship of power flow, especially for the recirculation power representation. Furthermore, a template model of multi-attribute topological graph for closed planetary gear trains is also presented, which would be helpful to the multi-attribute topological graph generation for some certain types of closed planetary gear trains just by changing symbols in the template model. A corresponding software is also developed to make the analysis process more convenient. By inputting different parameters, the different visual results can be obtained automatically, thus benefiting engineers in conceptual design.

Optimization of Lignin-Based Biocatalyst Production from Pine Sawdust and Wheat Straw.

Pine sawdust and wheat straw are abundant lignocellulosic wastes that have been recently converted into bioethanol under a biochemical platform scheme whose main waste is lignin. Lignin can be transformed into a wide variety of high added-value products, including its functionalization as a catalyst. A key step in the synthesis of a lignin-based catalyst is the sulfonation reaction, whose operating conditions, namely, H2SO4 to lignin ratio (mL/g), temperature and time, have been arbitrarily chosen. In this contribution, an optimization methodology (i.e., Box-Behnken) is applied in order to found the operating conditions during the sulfonation reaction that maximizes the total acid sites density of lignin-based catalysts from pine sawdust and wheat straw. The optimization results show that the time in sulfonation reactions can be significantly reduced, compared to those previously reported, without affecting the performance of both catalysts in esterification reactions. These results could be further considered for energy and costs reduction purposes during the conceptual design engineering of the sulfonation reaction.

System based on thermal control of the HCCI technology developed for reduction of the vehicle NOX emissions in order to fulfil the future standard Euro 7

On the present the environmental protection belongs among the most important worldwide priorities. From this reason there is valid within the framework of the European Union the standard Euro, which is specifically defined in the transport area. Nowadays the actual issue of this standard is signed Euro 6. It is established in order to eliminate most of the undesirable air pollutants. However, there is already prepared a new and even stricter emission standard Euro 7. It is a well-known fact that the actual emission standards are very hard and the automobile factories, together with the engine design concepts are trying to fulfil the new emission standards, mainly the NOX emission requirements. These circumstances also caused the infamous affair “dieselgate”. The new engine concept, which is called HCCI (Homogeneous Charge Compression Ignition), could be a suitable solution of the present NOX emission problems. Principle of the HCCI technology is based on self-ignition of the homogenous fuel mixture using compression in order to reduce emissions, whereas the NOX emission level is almost negligible. However, there are also several essential problems connected with the above-mentioned innovative technology, for example a high level of pressures arising during the compression process and intensive heat release. Another serious problem is a complicated control of the self-ignition process. This article presents an original technical solution, which enables to regulate the whole self-ignition process and in this way to ensure a reliable operation of the HCCI engine. We would like to emphasize also a fact that this unique solution was applied for a patent, as well. The innovated piston combustion engine was installed in the experimental vehicle designed for participation at the international competition shell eco marathon 2018 in London focused on minimisation of the fuel consumption.

Analysis of green environmental protection concept in environmental engineering design

With the development of China's economy, people's living standards are increasing, and the requirements for the living environment are also increasing. In order to meet the requirements of people's living environment while meeting the use of function, the idea of green environmental protection should be paid attention to in the process of engineering design. This paper analyzes the importance of the concept of green environmental protection, and analyzes how to adhere to the concept of green environmental protection.

Analysis of green environmental protection concept in environmental engineering design

With the development of China's economy, people's living standards are increasing, and the requirements for the living environment are also increasing. In order to meet the requirements of people's living environment while meeting the use of function, the idea of green environmental protection should be paid attention to in the process of engineering design. This paper analyzes the importance of the concept of green environmental protection, and analyzes how to adhere to the concept of green environmental protection.

A case study of mining-induced impacts on the stability of multi-tunnels with the backfill mining method and controlling strategies

Deep mining practices are jeopardized by the recurrent instability and failure of roadways/multi-tunnels. This paper describes a case study of the mining-induced impacts on the stability and control strategy of overlying multi-tunnels with backfill mining in the Ping Dingshan No. 10 Coal Mine in Henan Province, China. To reveal the dynamic impacts of coal mining on the stability of overlying multi-tunnels, particularly in the process of mining cycle and after the overlying strata long-term stability period, a 3D finite element model was applied to explore the effect of longwall panel width, advancing distance, and backfill material’s compaction ratio (BMCR) on the multi-tunnels’ deformation characteristics. The results obtained demonstrate that failure and deformation of the overlying multi-tunnels become more pronounced with the increased longwall panel width and advancing distance, as well as with BMCR reduction. The ranking of deformation degree in the overlying multi-tunnels is as follows: main haulage roadway > auxiliary haulage roadway > main inclined shaft > rock crosscut > auxiliary inclined shaft. Using a 2D physical simulation experiment, a comprehensive analysis method and engineering design concept for the stability control of overlying multi-tunnels with backfill mining are put forward based on further research of the deformation characteristics of multi-tunnels using caving and backfilling method. The results obtained are instrumental to the stability control of overlying tunnels in deep mining practices with similar conditions.

Post Evaluation on Convergence Project-based Instruction Model applying Concept of Creative Engineering Design in Technical High School

Post Evaluation on Convergence Project-based Instruction Model applying Concept of Creative Engineering Design in Technical High School

Constructive-regime parameters of rotor-brush cleaner for tuberous roots dry cleaning

Applying engineering design concepts and analysis, this work outlines the development of a small scale root cleaner from computer model simulation to a working prototype. The methodologies of mechanical design, material acquisition, construction and prototype testing are addressed. Results of researches of innovative technologies of tuberous roots cleaning process showed that efficiency increase of cleaning quality in the form of connected soil with vegetable remains depends on rational constructive-technological system and optimum constructive-regime parameters of device. Constructive-technological system of rotor-brush cleaner with justification of constructive-regime parameters is offered: brush angle, frequency of brush rotation, frequency of disk rotation. Quality of cleaning in this cleaner increases due to the application f rotor brush as working body which clears product in cleaning channel formed by disk, propeller and brush. Power consumption decreases as a result of application of propeller rational form and compact arrangement of working bodies.

Cyclical fatigue of annealed and of thermally tempered soda-lime-silica glass

We present experimental and theoretical investigations on the cyclic fatigue of annealed and of thermally tempered soda-lime-silica glass. Static fatigue due to subcritical crack growth at micro cracks significantly decreases the macroscopic strength of soda-lime-silica glass and causes a time-dependent strength reduction. A subsequent thermal tempering process is typically used to induce residual surface compression stresses, which inhibit the crack growth of surface cracks, and corresponding bulk tension stresses. From the experimental results we show that the existing models for static fatigue used in linear elastic fracture mechanics can be used for the lifetime prediction of cyclically loaded annealed glass and thermally tempered glass, although the (static) crack growth exponent slightly decreases in cyclic loading. The equivalent duration of tensile stress at the crack tip of a micro crack governs the crack growths and not the number of cycles. The threshold for subcritical crack growth determined from the cyclic experiments was found to be in good agreement with data from literature. But unlike in strength tests with singular and quasi-static re-loading, it could be found that periodic loading with load free intervals does not lead to a strength increase by crack healing effects. Based on the results, an engineering design concept for cyclically loaded glass is presented.

The Tao Way Follows Nature, The Highway Stems From Culture:The Application of Green Concept in Engineering Design of Tong-Huang Highway

The Highway from Tongling to Huangshan locates in the scenic area with two mountains and one lake (those are Yellow Mountain, Jiuhua Mountain and Taiping Lake). It is not only an important passageway in Anhui Province that connects the north and the south, but also a tourism corridor in the scenic area. During the design of the Project, the unique natural landscape in southern Anhui is taken into account; a design objective of bearing Hui culture and fitting in the landscape is set; a design philosophy of ecological road, tourism road, scientific road and cultural road is executed; and the old philosophical thought and design method of "the Tao way follows nature, the highway stems from culture is applied. Eventually an environmental friendly, resource-conserving,innovative and humanistic harmonious demonstration highway project is successfully made.

Idea-configuration-evaluation (ICE): development and demonstration of a new prescriptive model of the conceptual engineering design process based on parameter analysis and C–K theory

This paper introduces a new prescriptive model of conceptual engineering design. The model is based on the method called parameter analysis (PA) and the relatively new descriptive model called C–K theory. PA was developed based on observations of designers in action, while C–K theory has a strong foundation in logic theory. The new model combines the benefits of C–K theory and PA to overcome the lack of a strong theoretical foundation in PA and the insufficient prescriptive power of C–K theory. The paper describes in detail the process of developing the new model, which was similar to product development. It started with conceptualization in order to define a set of key factors and principles, i.e., the conceptual foundation or the “ideology” of the new prescriptive model. Next, those principles were integrated into a structured systematic procedure to form the new prescriptive model. The conceptual design of a realistic design task is used to demonstrate the application of the new model. The significance of the current work is the contribution to the theory and practice of engineering design, eventually leading to improved design processes and better designed products. Reporting on the experimental testing of the new model will follow in the future.

Identifying experts in the crowd for evaluation of engineering designs

ABSTRACTCrowdsourcing offers the opportunity to gather evaluations on concept designs from evaluators that otherwise may not have been considered, thus leveraging additional expertise to improve decision making during early stages of the design process. Previous research has shown that crowdsourcing may fail to evaluate correctly even ‘simple’ engineering design concepts, because non-expert evaluations overwhelm the entire crowd evaluation. This article proposes using expertise prediction heuristics to automatically identify experts and filter non-experts prior to a crowdsourced evaluation. We conducted an experiment to test four common expertise prediction heuristics: (1) evaluator demographics, (2) evaluation reaction time, (3) mechanical reasoning aptitude, and (4) ‘easy and known’ versions of the actual ‘difficult and unknown’ design evaluation task. The results show statistical significance between variables for all four heuristics; however, most predictive power is garnered going from easy to difficult tasks. A combination of these heuristics offers a practical way to identify and filter experts from non-experts, thus improving crowdsourced evaluation of early-stage design concepts.

Quality Improvement in Hot Dip Galvanizing Process Using Robust Design tools

This paper deals with the concept of quality engineering and robust design as one of the new practical methods for the improvement of galvanizing parameters design in order to obtain the best mechanical properties (hardness) by experimental design and robust design tools. By using Taguchi parameter design, three factors (controllable factors) were chosen, which are temperature, time, and withdraw speed, along with three levels for each factor to determine their effect on the hardness in galvanizing steel in order to obtain better quality levels. A L27(33) orthogonal array was selected and used in this experiment. 
 Minitab software was used in design and data analysis to achieve the desired quality objectives. Results show that the best combination to achieve a desired hardness were (T=455 ˚C, t=4 min., and S=6 m/min ). The experiment also revealed that the temperature and time have the largest effect on the hardness. In addition, the optimum condition was verified during the optimization stage using central composite design.

Tritium transport analysis for CFETR WCSB blanket

Water Cooled Solid Breeder (WCSB) blanket was put forward as one of the breeding blanket candidate schemes for Chinese Fusion Engineering Test Reactor (CFETR). In this study, a simplified tritium transport model was developed. Based on the conceptual engineering design, neutronics and thermal-hydraulic analyses of CFETR WCSB blanket, tritium transport process was analyzed. The results show that high tritium concentration and inventory exist in primary water loop and total tritium losses exceed CFETR limits under current conditions. Conducted were sensitivity analyses of influential parameters, including tritium source, temperature, flow-rate capacity and surface condition. Tritium performance of WCSB blanket can be significantly improved under a smaller tritium impinging rate, a larger flow-rate capacity or a better surface condition. This work provides valuable reference for the enhancement of tritium transport behavior in CFETR WCSB blanket.

Architectural Design Method of Architectural Engineering

After clearly defining the basic concept and category of architectural engineering and architectural design, this paper proposes basic requirements, and principles and mastery methods of design concept of architectural design, and describes dialectical thinking, system thinking and creative thinking method required in architectural design. To set up systematic architectural design methods, this paper explains the focus and requirements of the four stages of the architectural design: conceptual design, preliminary design, detailed design, and construction. Taking the China Pavilion at Expo 2010 Shanghai as an example, this paper analyzes design methods to solve the different problems in different design stages.

English

The aim of this research is to develop a learning model which blends factors from learning environment and engineering design concept for learning in computer programming course. The usage of the model was also analyzed. This study presents the design, implementation, and evaluation of the model. The research methodology is divided into three phases, they are: reviewing related literatures and surveying needs and problems in teaching computer programming in order to analyze and synthesize the elements of the model, developing a model which blends learning environment and learning activities based on engineering design processes, and evaluating the effects of using implemented environment on the learners’ programming conceptual understanding, problem-solving using programming skills, program analytical skills, and attitude in learning programming. The samples in this study include 8 experts who examine the tentative model and 52 undergraduate students of computer science program in Bansomdejchaopraya Rajabhat University, Thailand, to evaluate the implemented model. The student samples were separated into two groups which are control and experiment group. The results of the comparison between pre-test and post-test scores showed that the programming conceptual understanding, problem-solving by using programming skills, and program analytical skills of the students were significantly increased. In addition, in comparing between control and experiment groups, the scores of problem-solving using programming skills and program analytical skills of the experiment group are significantly higher than that of the control group. However, there were no significant differences in the scores of programming conceptual understanding between those groups. It was also found that the students in experiment group have a high attitude in learning programming in high level. Key words: Blended learning environment, engineering design concept, computer programming.