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This paper aims to explore how music festival organisers negotiate diversity and inclusion in marketing and promotion practices through symbolic and social boundaries.

Based on semi-structured interviews with 18 festival organisers in Rotterdam and participant observation with six festival photographers I show that symbolic and social boundaries are employed in three areas: (1) boundaries in festival format (i.e. [partially] free or ticketed), (2) boundaries in distribution partners and technologies and (3) boundaries in promotional content.

Symbolic and social boundaries are intentionally used by festival organisers to build and delineate festival audiences. Implications are drawn on current understandings of the accessibility of music festival spaces, arguing that festival research should move beyond within-space dynamics to grasp the negotiation of diversity and inclusion at festivals more fully.

While music festivals are often marketed as celebratory spaces that are “welcoming to everyone”, few studies have investigated diversity and inclusion nor marketing and promotion practices at music festivals. This study shows how festival audiences are shaped through marketing and promotion practices.

The paper aims to introduce a new algorithm based on the boundary integral method developed to solve moving boundary phase change problem subject to all possible cases of cyclic boundary temperature.

In the present paper, the phase change problem with periodic boundary temperature, which may be above or below the phase change temperature, is analyzed. The analysis is based on applying the boundary integral method in a new numerical algorithm. There are two main topics of the analysis herein. The first one is to study the direct effect of the cyclic boundary temperature on the movement of the moving boundary for various Stefan numbers. The second one is check that the proposed method covers all possible cases of cyclic boundary temperature with respect to the phase change temperature.

When using the proposed method, it is found an easy mathematical manipulation and the results can be improved when fine time step size used.

The proposed method is a very new method, which can be applied to any case of moving boundary phase change problem subject to any case of cyclic boundary temperature. Also the proposed method takes into consideration different parameters that affect directly on the evolution of the moving boundary such as Stefan number, etc.

The purpose of this paper is to investigate the effect a variety of different boundary layers have on a wing in ground‐effect.

Experiments were carried out in the University of Southampton's 3′×2′ wind tunnel. A variable length splitter plate was designed and manufactured in order to generate four boundary‐layer thicknesses at a selected measurement position. A single element inverted GA(W)‐1 aerofoil was then introduced to the flow at varying heights above the plate. Laser Doppler anemometry (LDA) and surface static pressure measurements (both on the aerofoil surface and on the splitter plate) were recorded.

The flow beneath the wing is found to be affected considerably by the presence of the boundary layer. As the boundary‐layer thickness is increased, the under‐wing pressure is observed to increase, hence resulting in decreased suction. Further, the LDA results indicate a modification to the wake profile. In particular, at low wing heights, the wake is observed to become entrained in the boundary layer, to differing degrees dependant on the boundary layer present and the wing height.

The acquisition of force values from the tests will have allowed further understanding of the “real world” implications of the presence of the boundary‐layer thicknesses on a wing in ground‐effect but this is not possible in the test facility used.

The aerodynamics of a wing in ground‐effect are of great interest for both lifting surfaces for aircraft and downforce generation in motorsport applications. The implications of this paper enhance the importance of understanding the boundary conditions present when wind tunnel testing for these applications.

Although the influence of the boundary layer on low ground clearance objects has been well documented, the methods used here, in particular the use of the pressure tapped splitter plate and LDA, allow a further insight into the explanations behind this influence.

An algorithm is presented for creating a flexible boundary to analyse three‐dimensional assemblies of spheres. It can be used to study localization phenomena in particulate materials. The boundary is composed of adjoining triangular plate elements which are connected at their corners to the centres of neighbouring spheres. The applied external boundary stresses create traction forces on the plates, which are distributed among the plates’ particles. The boundary performed favourably in tests on a large assembly of particles when only contact and rotational damping were used. Plane strain compression tests on assemblies with flexible and periodic boundaries revealed a lower strength with the former. This result could be due to the greater restraint on particle movements produced by periodic boundaries or to the early development of a column buckling failure pattern of the assembly with flexible boundaries. No shear bands were observed in the assembly.

The purpose of this paper is to describe the micro fluid flow analysis in a micro thruster of micro‐/nano‐ satellite propulsion system and to propose the algorithm for the fluid flow simulations with the open boundary based on moving boundary method.

The analysis is based on a finite volume moving boundary method. Underlying mathematical model is the system of Navier‐Stokes‐Fourier partial differential equation describing compressible gas model. Propellant under the study is pure nitrogen gas. First, the static geometry velocity vector field is calculated and the information of the velocity at the outflow boundary is obtained; then, with the moving boundary method the outlet boundary is evolved. Evolution of the boundary is stopped when the continuum model ceases to hold. The criteria of the continuum model failure are based on the local Knudsen number.

The validations of the flow with respect to the Knudsen number showed that the continuum model is valid in the nozzle interior part (from the pressure value to the nozzle throat). The exterior nozzle part (diverging side) showed immediate raising of the Knudsen number above the continuum threshold (0.01). For the overall accurate computations of thruster flow, the continuum model must be coupled with molecular model (i.e. Boltzmann BGK).

In this paper, the authors propose a method for the computation of an open boundary flow with the application of the moving boundary method.

A technique combining finite elements and boundary elements is promising for unbounded field problems. A hypothetical boundary is assumed in the unbounded domain, and the usual finite element method is applied to the inner region, while the boundary element method is applied to the outer infinite region. On the coupling boundary, therefore, both potential and flux must be compatible. In the finite element method, the flux is defined as the derivative of the potential for which a trial function is defined. In the boundary element method, on the other hand, the same polynomial function is chosen for the potential and the flux. Thus, the compatibility cannot be satisfied unless a special device is considered. In the present paper, several compatibility conditions are discussed concerning the total flux or energy flow continuity across the coupling boundary. Some numerical examples of Poisson and Helmholtz problems are demonstrated.

This paper presents a modification of the classical boundary integral equation method (BIEM) for two‐dimensional potential boundary‐value problem. The proposed modification consists in describing the boundary geometry by means of Hermite curves. As a result of this analytical modification of the boundary integral equation (BIE), a new parametric integral equation system (PIES) is obtained. The kernels of these equations include the geometry of the boundary. This new PIES is no longer defined on the boundary, as in the case of the BIE, but on the straight line for any given domain. The solution of the new PIES does not require boundary discretization as it can be reduced merely to an approximation of boundary functions. To solve this PIES a pseudospectral method has been proposed and the results obtained compared with exact solutions.

The boundary element method is a useful method for the analysis of field problems involving unbounded regions. Therefore, the method can be used advantageously in combination with the finite element method. This is sometimes called a combination method and it is suitable as a picture‐frame technique. Although this technique attains good accuracy, the matrix of the discretized equation is not banded, since it is a dense matrix. In this paper, we propose an infinite boundary element which divides the unbounded region radially. By the use of this element, the bandwidth of the discretized system matrix does not increase beyond that of the finite element region and its original matrix structure is maintained. The infinite boundary element can also be applied to homogeneous unbounded field problems, for which the Green's function of the mirror image is difficult to use. To illustrate the validity of the proposed technique, some numerical calculations are demonstrated and the results are compared with those of the usual combination method and the method using the hybrid‐type infinite element.

The purpose of this paper is to report a numerical solution for the problem of steady, two dimensional boundary layer buoyant flow on a vertical magnetized surface, when both the viscosity and thermal conductivity are assumed to be temperature-dependent. In this case, the motion is governed by a coupled set of three nonlinear partial differential equations, which are solved numerically by using the finite difference method (FDM) by introducing the primitive variable formulation. Calculations of the coupled equations are performed to investigate the effects of the different governing parameters on the profiles of velocity, temperature and the transverse component of magnetic field. The effects of the thermal conductivity variation parameter, viscosity variation parameter, magnetic Prandtl number Pm_r, magnetic force parameter S, mixed convection parameter Ri and the Prandtl number Pr on the flow structure and heat transfer characteristics are also examined.

FDM.

It is noted that when the Prandtl number Pr is sufficiently large, i.e. Pr=100, the buoyancy force that driven the fluid motion is decreased that decrease the momentum boundary layer and there is no change in thermal boundary layer is noticed. It is also noted that due to slow motion of the fluid the magnetic current generates which increase the magnetic boundary layer thickness at the surface. It is observed that the momentum boundary layer thickness is increased, thermal and magnetic field boundary layers are decreased with the increase of thermal conductivity variation parameter =100. The maximum boundary layer thickness is increased for =100 and there is no change seen in the case of thermal boundary layer thickness but magnetic field boundary layer is deceased. The momentum boundary layer thickness shoot quickly for =40 but is very smooth for =50.There is no change is seen for the case of thermal boundary layer and very clear decay for =40 is noted.

This work is original research work.

In conventional boundary element formulations, the singularities of the fundamental solution are usually located on the problem boundary. This leads to difficulties in evaluating solution quantities on or near the boundary. A method is presented for locating the singularities on an auxiliary boundary outside the problem domain and having this auxiliary boundary location determined automatically via a Galerkin criterion. This automatic generation of the auxiliary boundary results in a highly accurate, adaptive but non‐linear method. The number of singularities can be significantly reduced compared to conventional boundary element formulations which usually require the same number of singularities as the number of boundary elements used. The method is illustrated with three examples involving Laplace's equation in two dimensions. Excellent numerical results are obtained in all cases using only a few singularities.