Early Design Stage Research Articles

Pre-Design Selection of the Rated Power of a Heaving Point Absorber Wave Energy Converter

Wave energy converters (WECs) have significant potential for renewable energy generation, but early-stage design processes often require lengthy simulations. This study focuses on the pre-design selection of the rated power for a heaving point-absorber WEC. Addressing the gap in simplified methodologies, this study evaluates the wave energy resource, selects operational sea-states, and assesses device performance using time-domain simulations and linear potential flow theory. The results revealed that a WEC rated at 87% below peak power can capture 91% of the total available energy, achieving a balance between energy efficiency and cost-effectiveness. Furthermore, a simplified method to estimate rated power based on a constant ratio between mean and RMS power is proposed, offering significant potential for early-stage design applications. Future work should validate this approach across diverse WEC types and wave climates.

Decision-making in structural type selection at the early design stage in terms of carbon emissions and cost – Insights from case studies of port mooring facilities

Decision-making in structural type selection at the early design stage in terms of carbon emissions and cost – Insights from case studies of port mooring facilities

Evolving Tensegrity Façade Systems: Computational Morphogenesis through Multi-Step Optimization and Digital Fabrication of Structural Modules

In the field of façade design and engineering, the tensegrity structural principle may be utilized in pursuit of flexible, lightweight, and adaptable building envelopes. Depending on their geometry, tensegrity structures can form planar or nonplanar grids suitable for facades, and as prestressed structures, they tend to be resistant to dynamic loads such as seismic forces and wind. However, the form-finding process requires nonlinear analysis and physical simulations, and to optimize façade structures for a multitude of environmental objectives, computational analyses, and multi-objective optimization algorithms should also be implemented, which can further complicate the process. Addressing this challenge, this research introduces a tensegrity façade system developed through a multi-step approach. Initially, a simplified structural model is analyzed and optimized under assumed loads, which is then followed by the generation of a complex shape compression module, developed to account for a variety of environmental factors. This method enhances flexibility in the early design stages and provides an array of design solutions depending on the specific project requirements. The proposed system can provide high structural, material, and energy efficiency, and also improve the building occupants’ experience and comfort. The method was tested through computer simulations and produced results were built as physical mockups.

Early-stage design and development of mine waste valorisation technologies with expert input

Early-stage design and development of mine waste valorisation technologies with expert input

Product carbon emissions estimation method in the early design stage based on multi-perspective similarity matching of design scenarios

Product carbon emissions estimation method in the early design stage based on multi-perspective similarity matching of design scenarios

BIM-based embodied carbon evaluation during building early-design stage: A systematic literature review

BIM-based embodied carbon evaluation during building early-design stage: A systematic literature review

Multi-Objective Optimization of Daylighting–Thermal Performance in Cold-Region University Library Atriums: A Parametric Design Approach

Open atrium spaces in university libraries have emerged as a prevalent architectural trend. While increasing daylighting through enlarged glazing areas enhances the indoor environment, it simultaneously introduces significant thermal challenges in cold regions where environmental comfort demands lead to higher energy loads. This study investigates the optimization of daylighting–thermal performance balance through a multi-objective parametric approach to address the inherent conflicts between environmental quality and energy efficiency in atrium design. In this paper, we take the library project in the cold region as a practical case, use the measured data to support the simulation experiment, combine the parametric platform and multi-objective coupling optimization algorithm to carry out digital modeling, and explore the dynamic relationship between the atrium light, heat environment, and the value of energy consumption under the influence of a variety of parameters. The experimental results show that the quality and energy efficiency of the atrium light environment are improved after parameter optimization. The energy consumption per unit area (EUI) is reduced by 84.84 kwh/m2–106.83 kwh/m2 while the adequate natural illuminance (UDI) is increased by 5.06–27.64%, which confirms the feasibility of the research and development of the building light–heat coupling optimization technology route and program module. This paper aims to explore the quantitative law of design elements on light–heat balance at the early stage of architectural design and to provide a theoretical basis and reference blueprint for improving the comprehensive decision-making ability of architects in sustainable design and realizing integrated and efficient program decision-making.

Devising a method for assessing the performance of exergetic efficiency of a pressure wave exchanger

With all their undeniable advantages, forced engines equipped with gas turbine supercharging (GTS) have a significant inherent drawback of the turbocharger (TC), which is associated with the inertia of the TC rotor, causing a discrepancy between the flow characteristics of the supercharger and the hydraulic needs of the engine under transient modes, during sharp acceleration of the vehicle. As an alternative option and one of the effective methods for forcing the engine in order to obtain high technical, economic, and environmental performance indicators of the working process under transient operating modes, a wave pressure exchanger (WPE) is considered as the object of this study. However, the available information related to the energy exchange of working fluids in the units of the wave exchanger has not yet been sufficiently studied. To partially solve this problem, a method has been devised for assessing the exergetic efficiency of WPE, which takes into account the effect of partial exhaust gas recirculation, purging the rotor cells with a fresh charge. Based on the results of development studies, in the presence of a pattern of change in these parameters (purging and recirculation), it is possible to influence the process of improving the working cycle and the exergetic efficiency of the pressure exchanger. A rational combination of purging the rotor cells with a fresh charge (from 4 to 8 %) and reusing part of the combustion products (recirculation from 3 to 5 %) in the working process of the supercharger ensured an increase in the exergetic efficiency of WPE from 0.72 to 0.91 and partially solved the research problem. The resulting data can be implemented both at the early stages of WPE design and for existing modifications of supercharging units, in the process of their further modernization and improvement

Evaluating the usage of a building code calculator app as a design tool

Building code knowledge is essential for designers, but it can be challenging to learn and master. While automated code compliance tools assist in navigating these complexities, they are typically used later in the design process. This study introduces the Building Code Calculator App as an early-stage design tool. Grounded in cognitive load theory, the app simplifies information to simplify the learning process. It also incorporates concept mapping, a visual tool that aids in knowledge construction. This research aimed to examine the effectiveness of the Building Code Calculator App as a tool for design education. The app offers a visual guide to building codes and includes calculation features with explanations. It was hypothesized that the app would improve designers’ knowledge and skills while reducing their stress levels as they work on building code tasks. The study also predicts that the app will be adopted by designers in the future. A survey was conducted with senior interior design students after they completed a building code task using traditional methods and then used the app. All of the survey participants indicated the usefulness of the Building Code Calculator App in assisting the application of building code’s content and expressed disposition to use the app in the future. Results also confirmed that using the app lowered the participants’ stress levels, demonstrating its value as a design tool. In conclusion, these results advocate for a more comprehensive approach to building code education that leverages technology to provide practical, hands-on learning opportunities.

Incorporating Life Cycle Assessment and Uncertainties in Early Building Design: A Case Study Using Leaf Cutter Ant

To mitigate the impact of the climate, there is an advantage in incorporating climate calculations for design alternatives early in the design process. However, there is a need for tools dedicated to providing climate feedback on design sketches in the early design stages. A main actor in this stage is the architect. It is therefore beneficial if the toolchain already used by architects can be adapted to provide the necessary decision support for climate optimized design. For this purpose, a software tool called LCAnt version 0.2.2 was developed. This tool assists in determining amounts of materials from volume sketches in Rhino using a novel method for estimating the load-bearing structure and connecting it to an existing life cycle assessment database through Grasshopper. A real-life case study was used to demonstrate and evaluate how this type of tool can be applied in early design stages. This study was expanded by exploring strategies for managing uncertainties naturally present in these early design stages. This work demonstrates how to incorporate uncertainty evaluation into the early building design phase to obtain higher-quality decision support for low-climate-impact buildings. The uncertainty evaluation will at the same time identify in which stage important decisions regarding layout and material choices should be made to minimize the climate impacts of the finished building. Combining this with the studied tool LCAnt, which adapts to the workflow of professional building design, will facilitate implementation.

A method to determine the availability and performance of fixed-wing air taxis in real weather conditions for regional air mobility within Germany

The success of an on-demand air taxi transportation system depends, in part, on its availability during daily operations. To further analyze such a system, this paper introduces a method for determining the availability and performance of air taxis under real weather conditions. In the availability analysis, mainly the fulfillment of the visual meteorological conditions minima (VMC) is investigated, and in the performance analysis, it is checked if the performance is sufficient to operate in the given weather conditions. Therefore, the integration of weather data from the European Center for Medium-Range Weather Forecast (ECMWF) and real trajectories into the mission analysis tool of the aircraft preliminary design software Multidisciplinary Integrated Conceptual Aircraft Design and Optimization Environment (MICADO) for small aircraft is carried out for the first time. This allows the estimation of the performance of air taxis under real weather and operating conditions already at the aircraft preliminary design stage and potential technical deficits can be identified at an early design stage. Two single engine, fixed-wing air taxi designs, one with a hybrid-electric powertrain and one with an all-electric powertrain, are investigated in this paper. The results show that the availability is strongly limited by the VMC minima). The maximum availability of the short reference flight route between Nuernberg and Egelsbach is 41.78 % and the maximum availability of the long reference flight route between Augsburg and Moenchengladbach is 20.48 %. The availability of the hybrid-electric air taxi is not limited, as all investigated flights under sufficient VMC can be performed with this aircraft while complying with the required reserves. However, the availability of the all-electric air taxis is limited due to its performance. Because of adverse wind conditions, not all flights investigated under sufficient VMC can be performed with the all-electric air taxi while complying with the required reserves, as the energy demand is too high. For the all-electric air taxi operating on the short reference flight route, a 13.2 % increase in gravimetric battery energy density (GBED) is needed to ensure sufficient performance. The findings indicate the necessity of considering the real operating conditions in the preliminary design of small aircraft.

Impact Analysis of Building Structure on Building Envelope Design in the Context of Sustainability

This study examines the impact of the building structure on the building envelope in line with sustainable design goals. The building envelope plays a critical role in energy efficiency, conservation of natural resources, and reduction of environmental impacts with its design components such as form, facade, roof, and orientation. The study analyzed sustainable building examples accepted in the international literature, and the building structure's design flexibility and performance advantages were evaluated. The findings show that innovative building systems such as steel, wood, and precast concrete provide significant advantages in sustainable design processes. Structural elements that allow for wide openings and are recyclable increase the building envelope's energy efficiency. The results reveal that the building structure is not only structural durability but also a strategic component in achieving sustainability goals. In this context, it is emphasized that structural elements should be planned at the early design stage.

Early-Stage Design Optimization of Primary School Building’s Geometry with Reference to Energy Performance

Early-Stage Design Optimization of Primary School Building’s Geometry with Reference to Energy Performance

CAE Artificial Neural Network Applied to the Design of Incrementally Launched Prestressed Concrete Bridges

Bridges are typically designed by reputable, specialized engineering and design companies with years of experience. In these firms, experienced engineers share and pass on their knowledge to younger colleagues. However, when these experts retire, some of the knowledge is lost forever. As a subset of artificial intelligence methods, artificial neural networks (ANNs) can solve the problem of acquiring, transferring, and preserving specialized expert knowledge. This article describes the possible application of CAE ANN to acquire knowledge and to assist in the design of incrementally launched prestressed concrete bridges. Therefore, multidimensional graphs in the form of iso-curves of equal values were created, allowing practicing engineers to understand complex relationships between design parameters. The graphs also contain information about the reliability of the results, which is defined by an estimated parameter. The general rule is that results based on a larger number of actual data points are more reliable. Finally, an ANN BD assistant is proposed as an application that assists engineers and designers in the early stages of design and/or established engineers and designers in variant studies and design parameter optimization.

An Evaluation of the Accuracy of Existing Empirical and Semi-Empirical Methods for Predicting the Wing Mass of Large Transport Aircraft

This paper investigates and evaluates the accuracy of various empirical and semi-empirical methods for predicting aircraft wing-structure mass. Eight methods were selected and analysed using data from large passenger-transport aircraft. The required technical data variables and specifications associated with these methods of wing-mass estimation were identified. When data were unavailable, sound engineering assumptions and judgments were applied as a last resort. The root mean square percentage error (RMSPE) was employed as the comparative indicator of accuracy to compute the average discrepancy between the predicted and actual wing-mass values. The resulting RMSPE values were 10% for the Kundu method, 13% for the Torenbeek II method, 15% for the Basgall method, and 17% for the Howe and LTH methods. According to the findings, the Kundu and Torenbeek II methods achieved the highest accuracy, with nonsignificant differences in their RMSPE values. Predicted wing mass was within [−12.5%, +11.7%] of the actual wing mass in approximately 62% of the study cases, which is adequate for most conceptual and preliminary aircraft-design purposes. Predictions were within [−22.3%, +20.6%] for about 25% of cases and within [−39.0%, +29.7%] for about 13% of cases. Furthermore, more complex methods did not enhance accuracy, as essential variables for these methods are often unavailable during the early design stage, rendering their inclusion less practical. Based on the collected and analysed data, a new updated formula for estimating aircraft wing mass is introduced. In comparison to the methods previously discussed, the new formula yields a superior overall RMSPE of 11%, significantly improving the accuracy of wing-mass estimation. Specifically, the results show an RMSPE of 6.5% for aircraft with a maximum takeoff mass exceeding 300,000 kg and 13% for those with a maximum takeoff mass below 300,000 kg. The refined method proves effective for wings with an aspect ratio of up to 10, offering reasonable accuracy during the conceptual design phase. However, some discrepancies still arise when this method is applied to unconventional aircraft.

Investigation on the ventilation impact of enclosed-type teaching buildings under different aperture ratios and wind directions

ABSTRACT Enclosed-type of educational buildings, which are commonly seen in the campus nowadays, suffer from poor natural ventilation, causing higher energy consumption from mechanical ventilation as well as poorer indoor air quality. This study examines the natural ventilation performance of enclosed-type educational buildings in Qinhuangdao, China, with a focus on the effects of building aperture ratios and wind directions. The analysis considers aperture ratios ranging from 0% to 100% and wind angles from 0°to 180°, assessing wind velocity distribution and age of air within the rooms. The results indicate that natural ventilation is most effective when the aperture ratio is approximately 60%, which enhances space utilization and occupancy rates. Furthermore, aligning building openings with the prevailing wind direction optimizes ventilation efficiency. The study also reveals that ventilation performance varies across different room types and building locations, suggesting that strategic room arrangement can further improve ventilation outcomes. These findings highlight the importance of incorporating natural ventilation strategies in the early stages of architectural design, with potential benefits for energy conservation, indoor air quality, and public health.

A Comparative Analysis of the Spatial Design Perspective of Wayfinding: The Emergency Room as a Case Study

Medical buildings, particularly emergency rooms, can be challenging to navigate, leading to stress and time loss for users if spatial layouts are poorly organized. This study focused on the concept of wayfinding, particularly on oral and visual communication, which has been identified as a human factor influencing the wayfinding process. This study aimed to examine the spatial design phase of emergency rooms in terms of wayfinding. The study approach used quantitative and qualitative methods. A literature review and observations during field visits were carried out. During the field visits, the researchers considered the numbers of human factors in the emergency rooms. Space syntax software was used to analyze the architectural plans from the perspectives of (1) visibility and (2) connectivity, examining the location of human factors in the architectural layouts. A comparative study of three cases in the United Arab Emirates was performed. The following human factors were identified: receptions and two categories of nurse stations, namely, first-look nurse stations (FLNSs) and observation nurse stations (ONSs). The results demonstrate the need for a developmental phase regarding the spatial arrangements of human components, guided by a space syntax analysis, to enhance the wayfinding process in the three emergency room cases. This study provides various recommendations for the repositioning of the human factors in the three case studies: for case study “A”, one of the three human elements should be modified; for case study “B”, only one of the two human elements should be altered; and, for case study “C”, all three human components should be moved to an advantageous position based on the spatial data. The conclusion illustrates the feasibility of adopting a spatial analysis approach for emergency rooms in the early design stages.

Using a Novel Co-Design Prototyping Approach for System-in-Package Devices

System technology co-design (STCO) is the critical process of optimizing the interface between integrated IC device(s), package, and printed circuit board (PCB) at the early stages of product design and development. STCO can avoid poor system planning which could otherwise impact cost, yield, and performance. This paper focuses on the challenges and opportunities of STCO for system-in-package (SiP) and multi-chip package (MCP) solutions, which use a combination of wire bond and flip-chip die as well as SMT (surface mount technology) passive components. A scalable methodology is presented that uses Xpedition Substrate Integrator, a software tool for single-die ASIC and 2.5/3D packaging that automates the optimization of the system-level netlist, to achieve robust floorplanning and connectivity efficiency for SiP co-design. Compared to manual methods, this specialized workflow on typical SiP designs reduced up to 10-14% decrease in net congestions, leading to improvements in form factor, cycle time, and performance.

Panel Method for 3D Inviscid Flow Simulation of Low-Pressure Compressor Rotors with Tip-Leakage Flow

This paper presents a low-order three-dimensional approach for predicting the inviscid flow around low-pressure compressors. The method is suitable for early design stages and allows a broad exploration of design possibilities at minimal cost. It combines the vortex lattice method with the panel method by using a mixed boundary condition. In addition, it models the tip-leakage flow using an iterative algorithm. First, the verification of the approach is carried out on a low-pressure compressor configuration. The wake length is a decisive parameter for ensuring correct flow deflection in ducted applications. A periodicity condition is introduced and validated, which reduces the computational and memory requirements. On average, the calculations take less than one minute in real time. The approach is validated on the same low-pressure compressor configuration. A good agreement is obtained with RANS concerning the mean flow and the tip-leakage flow characteristics. Sensitivity to the mass flow rate is also fairly well predicted, although discrepancies develop at lower mass flow rates.

Tan House Footbridge: Designing with repurposed steel, from early design stages to fabrication

Tan House Footbridge was a collaboration between Network Rail, WSP UK and Format Engineers. The use of repurposed steel has been central to the design process, made possible by creative digital techniques that facilitated a refinement of structural typology to match the available stock of previously unwanted material. The use of generative digital methods permitted an iterative and flexible design process that allowed any material and embodied carbon savings arising from different options to be tracked at each step towards fabrication. The collaboration is a good illustration of how to achieve carbon reduction by making informed early design decisions. The bridge was designed, detailed and fabricated between February 2022 and October 2024. At the time of writing, the authors believe Tan House to have the lowest embodied carbon of any footbridge which Network Rail has constructed on a live site. An internal Network Rail/design team study has determined that Tan House is considerably lower in CO2 than the Network Rail standard Series 400 steel rail bridge. It is testament to the fact that a bespoke and site-appropriate design does not have to be costly in capital expenditure or embodied carbon. This article describes the workflow used to deliver the bridge and shares lessons learned by the team on the use of repurposed/reclaimed material within the design and procurement process.