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This paper aims to provide the results of investigations concerning an influence of the tyre with longitudinal grooves on the car body aerodynamics. It is considered as an important aspect affecting the vehicle aerodynamic drag.

To investigate a contribution of grooved tyres to the overall vehicle drag, three wind tunnel experimental campaigns were performed (two by Peugeot Société Anonyme Peugeot Citroen, one at the Lodz University of Technology). In parallel, computational fluid dynamics (CFD) simulations were conducted with the ANSYS CFX software to enable formulation of wider conclusions.

The research shows that optimised tread patterns can be derived on a single tyre via a CFD study in combination with a controlled experiment to deliver designs actively lowering the overall vehicle aerodynamic drag.

A reduction in the aerodynamic drag is one of ways to decrease vehicle fuel consumption. Alternatively, it can be translated into an increase in the maximum travel velocity and the maximum distance driven (key factor in electric vehicles), as well as in a reduction of CO₂ emissions. Finally, it can improve the vehicle driving and steering stability.

The tyre tread pattern analysis on isolated wheels provides an opportunity to cut costs of R&D and could be a step towards isolating aerodynamic properties of tyres, irrespective of the car body on which they are applied.

The purpose of this paper is to gain a better understanding of the flow field structure around the race car in two cases: stationary wheel and rotating wheel. In addition, this paper also illustrates and clarifies the influence of wheel rotation on the aerodynamic characteristics around the race car.

The author uses steady Reynolds-Averaged Navier-Stokes (RANS) equations with the Realizable k-ε model to study model open-wheel race car. Two cases are considered, a rotating wheel and stationary wheel.

The results obtained from the study are presented graphically, pressure, velocity distribution, the flow field structure, lift coefficient (C_l) and drag coefficient (C_d) for two cases and the significant influence of rotating case on flow field structure around wheel and aerodynamic characteristics of race car. The decreases in C_d and C_l values in the rotating case for the race car are 16.83 and 13.25 per cent, respectively, when compared to the stationary case.

Understanding the flow field structures and aerodynamic characteristics around the race car in two cases by the steady RANS equations with the Realizable k-ε turbulence model.

The paper proposes a study of a GT2 racing car with a computational fluid dynamic (CFD) tool. Results of STAR-CCM+ simulations of the flow around the car in a wind tunnel with movable ground and wheels are presented for different air speeds to assess the different contributions of pressure and shear to lift and drag over the speed range. The rear wing contributes more than 85% of the lift force and 7-8% of the drag force for this particular class of racing cars. When reference is made to the low speed drag and lift coefficients, increasing the speed from 25 to 100 m/s produces an increase of CD of more than 3% and a reduction of CL of more than 2%. The resultsuggests modifying the constant CD and CL values used in lap time simulation toolsintroducing the tabulated values to interpolate vs. the speed of the car.

This paper seeks to reduce the time it takes to perform external aerodynamic simulations without compromising accuracy. At present, cleaning up CAD data sets, in particular for undercarriage parts, takes several man‐weeks.

Body‐fitted and embedded mesh techniques are combined to obtain accurate external aerodynamic solutions for realistic car geometries with minimal user intervention. The key idea is to mesh with typical body‐fitted RANS grids the external shape of the vehicle, which is smooth and requires detailed physical modeling. The underhood and undercarriage are treated as embedded surfaces. The flow in this region is massively separated, requiring LES runs and isotropic grids. This makes it a suitable candidate for embedded grids.

Comparisons with body‐fitted and experimental data for a typical car show that this approach can yield drag predictions with an error less than 5 percent.

The present approach reduces turnaround times for complete car geometries to one to two days, without compromising accuracy.

To the authors' knowledge, this is the first time such an approach has been tried and validated for external aerodynamics.

The literature on interfirm networks devotes scant attention to the ways collaborating firms combine and integrate the knowledge they share and to the subsequent learning outcomes. This study aims to investigate how motorsport companies use network ties to share and recombine knowledge and the learning that occurs both at the organizational and dyadic network levels.

The paper adopts a qualitative and inductive approach with the aim of developing theory from an in‐depth examination of the dyadic ties between motorsport companies and the way they share and recombine knowledge.

The research shows that motorsport companies having substantial competences at managing knowledge flows do so by getting advantage of bridging ties. While bridging ties allow motorsport companies to reach distant and diverse sources of knowledge, their strengthening and the formation of relational capital facilitate the mediation and overlapping of that knowledge.

The analysis rests on a qualitative account in a single industry and does not take into account different types of inter‐firm networks (e.g. alliances; constellations; consortia etc.) and governance structures. Cross‐industry analyses may provide a more fine‐grained picture of the practices used to recombine knowledge and the ideal composition of inter‐firm ties.

This study provides some interesting implications for scholars and managers concerned with the management of innovation activities at the interfirm level. From a managerial point of view, the recognition of the different roles played by network spanning connections is particularly salient and raises issues concerning the effective design and management of interfirm ties.

Although much of the literature emphasizes the role of bridging ties in connecting to diverse pools of knowledge, this paper goes one step further and investigates in more depth how firms gather and combine distant and heterogeneous sources of knowledge through the use of strengthened bridging ties and a micro‐context conducive to high quality relationships.

This study aims to reduce the weight of the door, improve the operating efficiency and ensure the safety of vehicle operation.

Based on traditional aluminium alloy doors, a new type of honeycomb composite material was developed. Tests were conducted to determine the honeycomb compression resistance, honeycomb and skin shear performance, plate bending, thermal conductivity and environmental protection. Eight doors were developed based on the full-side open structure, and static strength and stiffness analyses were performed simultaneously. To solve door vibration problems, modal analysis and test were carried out.

The test results showed that the weight of the door was reduced by more than 40% whilst ensuring the strength and stiffness of the vehicle. The first–sixth-order test mode of the door was increased by more than 14% compared with existing aluminium alloy doors.

A new type of honeycomb composite material was used in this study. The test results showed that the weight of the door was reduced by more than 40% whilst ensuring the strength and stiffness of the vehicle. The 1st-to-6th order test mode of the door was increased by more than 14% compared with the existing aluminium alloy door.

Styling is plagued by prejudice in the literature on the management of design – making it a taboo to talk about styling and designers as stylists. At the same time, the ability of designers to shape the look and feel of products still represents the most defining work of designers. However, reduced to superficial changes in form, styling has been misrepresented as simplistic decoration that is of limited strategic interest for managers of design, especially when compared to the more immaterial (processual) qualities that the discipline has to offer.

In this chapter, we question the validity of the conceptualization above, arguing for a renewed interest in the work of designers as stylists. Building on a general reassessment of style in art and design, we appropriate Ackerman's (1962) work on style for studies on styling and the management of design. In doing so, we propose that styling relates to the problem-solving activities of companies, in which designers create and shape solutions and their expressions. By defining styling along these lines, we account for the ‘‘everyday’’ view that designers (as stylists) shape the look and feel of products, but we no longer disregard the central concern of designers to integrate their decisions on form and function when shaping the look and feel of new products in practice.

This paper aims to examine how long-lived firms can further develop through digitalisation in terms of actions, conditions and effects from a competitiveness perspective.

This exploratory study follows an inductive approach based on a survey conducted via interviews undertaken with nine long-lived Italian firms. The dimensions of the model (command, continuity, community, connection), elaborated by Miller and Le Breton-Miller (2005) in relation to longevity factors, were chosen to analyse digitalisation’s contribution to these long-lived firms’ development.

The digitalisation implemented by the analysed firms contributed in a variety of ways: (1) improved the efficiency and effectiveness of their business processes, (2) enhanced the understanding of customer experience, (3) supported their craftsmanship and the transmission of the knowledge included in the entrepreneurial path, (4) increased the awareness of the cultural value of the firms’ heritage and (5) allowed for the development of cutting-edge design skills by experimenting with content on different digital platforms and devices.

This study suggests managers of long-lived firms develop digital skills that allow them to interact with the rapid evolution of this context and understand how to effectively implement digitalisation in their specific firm. From this perspective, it is strategic to establish or strengthen collaborative network relationships to acquire such necessary skills.

This study provides novel empirical evidence on how long-lived firms are facing the challenge of digitalisation in terms of actions, conditions and effects to improve their competitiveness and ensure their survival.

This study aims to achieve optimum flow separation control for a road vehicle using a reverse flow fan on rear side.

A full-length reverse flow fan array (fan’s air speed is 50% of the car’s speed) is attached throughout the width of the vehicle at rear edge corner.

The reverse flow fan array positioned at rear edge of car pushes the airflow against the car’s rear window. It creates the recirculation region and alters the pressure distribution. This reduces the lift coefficient by 150%, which becomes the downforce and reduces the drag coefficient by 22%. As the car speed increases, fan speed should also be increased for effective flow control.

This active flow control method for 3D Ahmed car body has been studied computationally at low speed (40 m/s).

This design increases the downforce, thus gives better cornering speed and stability, and decreases the drag which improves fuel efficiency. It can be used for effective flow control of cars (hatchback/sedan). The findings can be applied to the bluff bodies, road vehicles, UAV and helicopter fuselage for flow separation control.

The fan array is attached on car’s rear side, which blows air against the car’s rear window. It alters the pressure distribution and aerodynamics forces favorably. But the existing high-speed fan used in a sports cars sucks the air from bottom and pushes it rearward, which increases both the traction force and drag.

The purpose of this study is to propose a precise and standardized strategy for numerically simulating vehicle aerodynamics.

Error sources in computational fluid dynamics were analyzed. Additionally, controllable experiential and discretization errors, which significantly influence the calculated results, are expounded upon. Considering the airflow mechanism around a vehicle, the computational efficiency and accuracy of each solution strategy were compared and analyzed through numerous computational cases. Finally, the most suitable numerical strategy, including the turbulence model, simplified vehicle model, calculation domain, boundary conditions, grids and discretization scheme, was identified. Two simplified vehicle models were introduced, and relevant wind tunnel tests were performed to validate the selected strategy.

Errors in vehicle computational aerodynamics mainly stem from the unreasonable simplification of the vehicle model, calculation domain, definite solution conditions, grid strategy and discretization schemes. Using the proposed standardized numerical strategy, the simulated steady and transient aerodynamic characteristics agreed well with the experimental results.

Building upon the modified Low-Reynolds Number k-e model and Scale Adaptive Simulation model, to the best of the authors’ knowledge, a precise and standardized numerical simulation strategy for vehicle aerodynamics is proposed for the first time, which can be integrated into vehicle research and design.