Flow Dynamics Over Two Cylinders in Tandem Subjected to Different Heating Cases

Heated and unheated flows with forced convection over two fixed circular cylinders in tandem are studied numerically for 80 ≤ Re ≤ 250 and 1 ≤ T* ≤ 2.3. Three different spacing ratios (L/D) = [2, 4, 8] are considered under three heating conditions. The scenarios considered are (1) heated upstream and unheated downstream cylinders, (2) unheated upstream and heated downstream cylinders and (3) heated upstream and downstream cylinders. These scenarios represent the limiting case for a cross-flow heat exchanger, where the downstream tubes are at increasingly lower or higher temperature for cooling or heating, respectively. The global aerodynamic forces on the cylinder as vortices shed was investigated. The flow is visualized by plotting the streamlines, temperature fields, and velocity magnitude contours for the different spacing ratios and compared to the flow regimes in literature namely, Extended-body, Reattachment, and Co-shedding regimes. The drag and surface heat transfer coefficients are analyzed for different scenarios. The effect of heating on the fluid properties and the resulted wakes in the flow are found to be strongly influenced by Re and L/D. The scenario of heated upstream and unheated downstream cylinders was found to increase the mean drag coefficient Cd on the upstream cylinder for L/D = 2 & 4 but is not as evident for the downstream cylinder. The heat transfer coefficient h on the upstream cylinder remained approximately the same regardless of a heated or unheated downstream cylinder. In contrast, h of the downstream cylinder decreases for the scenario of heated upstream and downstream cylinder.

Extended body … extended mind: The risk of thought

Communication may be understood through its manifest meaning or through the medium in which it is expressed. The latter approach begins from the material social relations and technologies that constitute the medium of communication. This approach has a certain similarity with affect theory understood as a pre-cognitive focus on bodies and technologies. An affective network sets up the manifest subject–object, or human–machine, relations with a subjectified anxiety. The objectification of intelligence produces a fundamental anxiety about what it is to be human. I attempt to determine where thought may yet intervene in a world of algorithms which is pervaded by anxiety.

Whatever Next and Close to my Self – The Transparent Senses and the ‘Second Skin’: Implications for the Case of Depersonalisation

In his seminal paper ‘Whatever next? Predictive brains, situated agents, and the future of cognitive science’ Andy Clark (2013) argued that the brain’s job is to predict whatever information is coming ‘next’ on the basis of the prior information perceived before. In this paper we suggest that term ‘next’ should be understood not only at the temporal scale (i.e. what is perceived in the upcoming second); but (ii) also from a spatial dimension (i.e. what is perceived literally next to or close-to-my-body). We examine the perceptual processing of proximal sensory inputs which have a key impact on the organism’s survival. Specifically, we focus on tactile experiences that extend to the immediate objects/materials that envelop closely our skin, namely clothes. One relatively overlooked aspect of our experiences is that humans in modern societies spend most of their lives having their bodies closely enveloped by materials/textile. Following the seminal ‘extended mind’ thesis (Clark & Chalmers 1998; Kirchhoff & Kiverstein 2019), we argue that these materials may be conceived as a ‘second skin’ or ‘extended skin’ that underwrite what we will call here ‘extended body-image’ and ‘extended body-schema’ (cf. Gallagher 2005). We argue that tactile experiences – mediated by the skin and the ‘extended skin’ – may be viewed as a ‘transparent bridge’ intrinsically relating and facilitating exchanges between the self and the physical and social world. Contrary to the standard approach that views the skin (and tactile experiences) as a mere border separating the self and world, here we propose that the skin (and its extended version, ‘the second skin’, i.e. the clothes) simultaneously and inherently distinguish and connect the bodily self to its environment. We conclude with potential implications of this observation for the case of Depersonalisation Disorder, a condition that makes people feel estranged and detached from one’s self, body and the world.

A New Form of Modern Sport: The Beginnings of Lakeland Rock Climbing 1880–1914

The English Lake District played a key role in British rock climbing and is arguably the place where rock climbing first separated from mountaineering in the 1880s. This article sets its origins in the wider context of Alpinism. It then explains the attractions of the Lake District to early climbers and the ways and locations in which early rock climbing emerged as key participants exploited the landscape to create the innovative rock climbing challenges that were key to their enjoyment. It provides rich detail on how the sport extended body limits, developed new climbing techniques, and used better equipment. Leading climbers there began to record and measure the standard of climbs—another innovation. Although mountaineering clubs elsewhere were exclusively male, relegating leading women mountaineers to a marginal role, in the Lakes, women rock climbers made a notable contribution. The article concludes by evaluating the wider significance of the Lake District for British climbing.

TELESAR VI: Telexistence Surrogate Anthropomorphic Robot VI

Telexistence refers to the general technology that allows humans to experience the real-time sensation of being in another place, interacting with a remote environment, which may be real, virtual, or a combination of both. It also refers to an advanced type of teleoperation system that allows an operator behind the controls to perform remote tasks dexterously with the feeling of being in a surrogate robot working in a remote environment. Telexistence in a real environment through a virtual environment is also possible. The concept was originally proposed by the first author in 1980, and its feasibility has been demonstrated through the construction of alter-ego robot systems called Telexistence Surrogate Anthropomorphic Robot (TELESAR) I–V. TELESAR VI is a newly developed telexistence platform for the ACCEL Embodied Media Project. It was designed and implemented with a mechanically unconstrained full-body master cockpit and a 67 degrees-of-freedom (DOF) anthropomorphic avatar robot. The avatar robot can operate in a sitting position since the main area of operation is intended to be manipulation and gestural. The system provides a full-body experience of our extended “body schema,” which allows users to maintain an up-to-date representation in space of the positions of their different body parts, including their head, torso, arms, hands, and legs. All ten fingers of the avatar robot are equipped with force, vibration, and temperature sensors and can faithfully transmit these elements of haptic information. Thus, the combined use of the robot and audiovisual information actualizes the remote sense of existence, as if the users physically existed there, with the avatar robot serving as their new body. With this experience, users can perform tasks dexterously and feel the robot’s body as their own, which provides the most simple and fundamental experience of a remote existence.

Numerical Investigation of Flow around Two Tandem Identical Trapezoidal Cylinders

The trapezoidal beam structure is ubiquitous in giant engineering equipment, while their aerodynamic characteristics have not been clearly understood. Numerical simulation method was adopted to investigate the flow around two tandem identical trapezoidal cylinders. The study was conducted using a Reynolds number of 2.2 × 104, and with a spacing ratio varying from 0.5 to 10. The incompressible two-dimensional finite volume method was used for solving Reynolds-Averaged Navier–Stokes (RANS) equations with realizable k−ε model. The effects of cylinder geometry and spacing between the cylinders on aerodynamic characteristics, unsteady flow patterns, time-averaged flow characteristics, and flow instability was studied. The results show that the flow around the two tandem trapezoidal cylinders is highly dependent on the spacing ratio. The flow modes can be classified into: extended-body regime (Mode I, S∗ ≤ 1), reattachment regime (Mode II, 2 ≤ S∗ ≤ 3), and binary regime (Mode III, S∗ ≥ 4). We explored their respective flow characteristics and distinctions through the force/pressure coefficients, time-average streamwise velocity, and the flow field evolution.