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The purpose of this study is to model the dynamic characteristics of an opened supersonic disk-gap-band parachute.

A fluid-structure interaction (FSI) method with body-fitted mesh is used to simulate the supersonic parachute. The compressible flow is modeled using large-eddy simulation (LES). A contact algorithm based on the penalty function with a virtual contact domain is proposed to solve the negative volume problem of the body-fitted mesh. Automatic unstructured mesh generation and automatic mesh moving schemes are used to handle complex deformations of the canopy.

The opened disk-gap-band parachute is simulated using Mach 2.0, and the simulation results fit well with the wind tunnel test data. It is found that the LES model can successfully predict large-scale turbulent vortex in the flow. This study also demonstrates the capability of the present FSI method as a tool to predict shock oscillation and breathing phenomenon of the canopy.

The contact algorithm based on the penalty function with a virtual contact domain is proposed for the first time. This methodology can be used to solve the negative volume problem of the dynamic mesh in the flow field.

This study aims to investigate the morphing concepts able to manipulate the dynamics of the downstream unsteadiness in the separated shear layers and, in the wake, be able to modify the upstream shock–boundary layer interaction (SBLI) around an A320 morphing prototype to control these instabilities, with emphasis to the attenuation or even suppression of the transonic buffet. The modification of the aerodynamic performances according to a large parametric study carried out at Reynolds number of 4.5 × 10⁶, Mach number of 0.78 and various angles of attack in the range of (0, 2.4)° according to two morphing concepts (travelling waves and trailing edge vibration) are discussed, and the final benefits in aerodynamic performance increase are evaluated.

This article examines through high fidelity (Hi-Fi) numerical simulation the effects of the trailing edge (TE) actuation and of travelling waves along a specific area of the suction side starting from practically the most downstream position of the shock wave motion according to the buffet and extending up to nearly the TE. The present paper studies through spectral analysis the coherent structures development in the near wake and the comparison of the aerodynamic forces to the non-actuated case. Thus, the physical mechanisms of the morphing leading to the increase of the lift-to-drag ratio and the drag and noise sources reduction are identified.

This study investigates the influence of shear-layer and near-wake vortices on the SBLI around an A320 aerofoil and attenuation of the related instabilities thanks to novel morphing: travelling waves generated along the suction side and trailing-edge vibration. A drag reduction of 14% and a lift-to-drag increase in the order of 8% are obtained. The morphing has shown a lift increase in the range of (1.8, 2.5)% for angle of attack of 1.8° and 2.4°, where a significant lift increase of 7.7% is obtained for the angle of incidence of 0° with a drag reduction of 3.66% yielding an aerodynamic efficiency of 11.8%.

This paper presents results of morphing A320 aerofoil, with a chord of 70cm and subjected to two actuation kinds, original in the state of the art at M = 0.78 and Re = 4.5 million. These Hi-Fi simulations are rather rare; a majority of existing ones concern smaller dimensions. This study showed for the first time a modified buffet mode, displaying periodic high-lift “plateaus” interspersed by shorter lift-decrease intervals. Through trailing-edge vibration, this pattern is modified towards a sinusoidal-like buffet, with a considerable amplitude decrease. Lock-in of buffet frequency to the actuation is obtained, leading to this amplitude reduction and a drastic aerodynamic performance increase.

Purpose – The purpose of this chapter is to differentiate between a sociology of the body and an embodied sociology, prior to considering what this might mean in methodological terms for those wishing to conduct research into the senses and the sensorium in sport and physical culture.

Design/methodology/approach – The approach taken involves reviewing the work of those who have already engaged with the senses in sport and physical culture in order to highlight an important methodological challenge. This revolves around how researchers might seek to gain access to the senses of others and explore the sensorium in action. To illustrate how this challenge can be addressed, a number of studies that have utilised visual technologies in combination with interviews are examined and the potential this approach has in seeking the senses is considered.

Findings – The findings confirm the interview as a multi-sensory event and the potential of visual technologies to provide access to the range of senses involved in sport and physical culture activities.

Research limitations/implications – The limitations of traditional forms of inquiry and representational genres for both seeking the senses and communicating these to a range of different audiences are highlighted and alternatives are suggested.

Originality/value – The chapter's originality lies in its portrayal of unacknowledged potentialities for seeking the senses using standard methodologies, and how these might be developed further, in creative combination with more novel approaches, as part of a future shift towards more sensuous forms of scholarship in sport and physical culture.

In Western liberal democracies over the last decade or so, community development, housing policy and neighbourhood renewal have been increasingly underscored by a philosophy of participatory decision-making (see Imre & Raco, 2003; Lo Piccolo & Thomas, 2003; Maginn, 2004). At one level, it appears that central and local governments have experienced a policy and democratic epiphany. This is reflected in a ‘new’ acknowledgment that ‘when citizens themselves are the key to the quality of neighbourhoods, a new avenue of policy intervention is opened up’ (Lelieveldt, 2004, p. 534; see also Crenson, 1983). In this context, participatory models of decision-making are seen as having the potential to ‘empower’ local residents who were previously the subject of ‘top-down’ or command and control forms of planning (Healey, 1999; Meredyth, Ewing, & Thomas, 2004; Barry, Osborne, & Rose, 1996; Rose, 1996; Dean, 2002). On another level, however, there is caution, suspicion even, about this paradigm shift. A perception exists that governments are essentially displacing, redistributing and/or retreating from their historical welfare responsibilities (Chaskin, 2003, 2001; Fraser, Lepofsky, Lick, & Williams, 2003; Pierre, 1999).

Literature from across the social sciences and research evidence are used to highlight interdisciplinary and intersectional research approaches to food and family. Responsibilisation emerges as an important thematic thread, as family has (compared with the state and corporations) been increasingly made responsible for its members’ health and diet.

Three questions are addressed: first, to what extent food is fundamentally social, and integral to family identity, as reflected in the sociology of food; second, how debates about families and food are embedded in global, political and market systems; and third, how food work and caring became constructed as gendered.

Interest in food can be traced back to early explorations of class, political economy, the development of commodity culture and gender relations. Research across the social sciences and humanities draws on concepts that are implicitly sociological. Food production, mortality and dietary patterns are inextricably linked to the economic/social organisation of capitalist societies, including its gender-based divisions of domestic labour. DeVault’s (1991) groundbreaking work reveals the physical and emotional work of providing/feeding families, and highlights both its class and gendered dimensions. Family mealtime practices have come to play a key role in the emotional reinforcement of the idea of the nuclear family.

This study highlights the imperative to take pluri-disciplinary and intersectional approaches to researching food and family. In addition, this paper emphasises that feeding the family is an inherently political, moral, ethical, social and emotional process, frequently associated with gendered constructions.

The purpose of this paper is to present a method for early crack detection in rotating shafts. A rotor-bearing system, consisting of an elastic rotor mounted on fluid film bearings, is used to detect the presence of the crack at a depth of around 5 percent of shaft radius. The fluid film bearings, the shaft and the crack introduce coupled bending vibrations both in the horizontal and vertical plane. Experimental time series of the rotor composite response under normal steady-state operation are uncoupled, to develop a signal processing procedure able to reveal the presence of the crack.

The variation of the coupling property that a crack (breathing or not) or a cut (always open) introduces into the system and the localization of the coupling in the time domain is a concept proposed as a means to detect transverse surface cracks in rotating shafts. This consideration is combined with the concept of external excitation for the development of an additional crack-sensitive response during system normal operation. Using an external excitation of an active magnetic bearing of specific duration, frequency and amplitude, the method uses this coupling variation during rotation.

The method is simple, quick and effective for early crack detection, being able to detect cracks as shallow as 5 percent of the shaft radius while the system is under normal operation, and can even be applied real-time. Experimental verification uses a simple elastic rotor with a cut mounted on fluid film bearings, with the cut producing similar coupling phenomena as an opened crack. Experimental results are encouraging.

The method used is simple, quick and effective for early crack detection, being able to detect cracks as shallow as 5 percent of the shaft radius while the system is under normal operation, and can even be applied real-time.

Stress damages us and our performance. It is a real part of most manager's experience and can be said to occur when significant demands exceed perceived management responsibilities and routines. Stress can be the essence of working life, and certainly need not always be damaging to us. But when it becomes excessive, it is something unwanted.

This chapter starts from the assertion that leading is a physically demanding activity. The challenges associated with it arise from at least three sources: as a response to ambiguous ‘wicked’ problems taking the lead necessitates moving into unknown situations; followers’ projections and the leader’s conscious or unconscious desire to fulfil them create psychological and emotional pressure and leaders often work in isolation. These realities of leading create physical stress that can result in disrupted sleep, digestive ailments and over-reliance on food and alcohol for short-term relief. Conscious breathing is introduced as a way of mitigating these physical effects. Such breathing can halt the vicious cycle of feeling stressed because one is breathing shallowly and breathing shallowly because of feeling stressed. Additionally, it can reduce the sense of time pressure by introducing an experience of greater spaciousness and provide a means whereby the leader can access her or his ‘best self’ in meeting the demands of the role. The ideas are illustrated through a case study of a senior executive who successfully used conscious breathing practices to transform the way in which he led his team.

The paper aims to focus on airflow and heat transfer inside the human nasal cavity. The contribution of this work is the inertial analysis of the momentum and thermal stress of the cavity throughout the respiratory cycle.

By means of computer tomography scans, an accurate three‐dimensional anatomical representation of the human nasal cavity was obtained. A three‐dimensional numerical model is presented in order to predict the time evolution of flow patterns during a quiet breathing cycle, covering inhalation and exhalation. An inertial analysis of the momentum and a detailed study of the thermal behaviour during the breathing cycle is carried out.

Head loss, velocity and temperature values are in agreement with experimental results from previous studies. Based on these results, the influence of the inhalation and the exhalation on the flow pattern and air conditioning has been reviewed. Results suggest that the anterior and posterior turbinate regions are where the air conditioning is primarily produced.

The future goal is to investigate respiratory disorders to increase the effectiveness of the eventual treatment of the pathology. The model could be a useful tool to predict, for instance, the modification of the flow patterns due to septal perforations.

The transient resolution provides insight into the momentum and thermal inertia though the breathing which is far from being well understood.

THE partial pressure of the oxygen content in the atmosphere decreases directly with the atmospheric pressure, i.e., with the altitude, the proportion of oxygen in the atmosphere (about 20·9 per cent) remaining practically constant in the substratosphere.