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The Department of Health's introduction of intermediate care recognised the need for rehabilitation following acute hospital care. The importance of rehabilitation was also stressed by a review carried out across England and Wales by District Audit. This article reports a phenomenological study carried out to explore service users' experiences of a 22‐bedded intermediate care service. Face‐to‐face, semi‐structured interviews were conducted with eight service users who were older people, with a further follow‐up interview two weeks later. Data was analysed using an open‐coding and theming approach. One of the six emergent themes is discussed in this article: service users' rehabilitation experiences. Data was themed into a rehabilitation framework of users' understanding, assessment and goal setting, interventions and transfer home. Intermediate care was found to provide support for service users between discharge from acute hospital and return to their own homes, but service users lacked understanding and awareness of the potential of the intermediate care service. They did not feel involved in their assessment and goal setting and so were unable to make individual contributions regarding their own rehabilitation needs. Interventions were subsequently not linked to their needs and transfer home experiences were variable. Users' experiences did not reflect the Department of Health's four principles that underpin the delivery of intermediate care: person‐centred care; whole system working; timely access to specialist care; promoting health and an active life. Recommendations are made to address these and to incorporate the recommendations from District Audit.

The purpose of this paper is to understand and develop ways to enhance patients’ experiences of preoperative education received prior to surgery for colorectal cancer.

Based in the UK, three-action research cycles were undertaken to evaluate preoperative education, identify changes seen by patients and staff as likely to improve the service and to re-evaluate such changes following implementation. Data in each cycle were collected from: observations of clinic interactions; patient questionnaires; individual semi-structured interviews with multidisciplinary colorectal unit staff; longitudinal semi-structured interviews with patients and carers pre-surgery, two weeks post-surgery and 12 weeks post-surgery; patient and carer focus groups post-surgery; and existing educational material.

In total, 138 participants shared their experiences of either giving or receiving preoperative education. Findings were themed into why patients want preoperative education, and patients’ views of the educational processes.

Patients emphasised the need for educational provision to be fully understandable, comprehensive and client-centred using a range of communication processes. Patients emphasised the need for educational provision to be more fully understandable, comprehensive and client-centred and that important messages should be reinforced using a range of media. At a time of many uncertainties for patients’ lives, such education needed to encompass the experiences patients could expect, delivered by confident healthcare professionals.

Contextualising understanding and facilitating their own actions, enabled patients to regain control in circumstances particularly disruptive of bodily and other life routines. Establishing a sense of control is confirmed as important for patient's wellbeing in preparing for surgery and postoperative rehabilitation.

The purpose of this paper is to evaluate the capacity of two equation turbulence models to reproduce mean and fluctuating quantities in the case of both natural convection and isothermal flows.

Numerical predictions of mean velocity profiles, air and wall temperatures as well as turbulent kinetic energy by three different two equation models (standard k‐ε, renormalisation group k‐ε and shear‐stress transport‐k‐ω) are compared with corresponding experimental values.

The prediction of mean velocities and temperatures is in all cases satisfactory. On the other hand, the prediction of turbulent quantities is less precise.

The three models under consideration in this paper can be used for engineering applications such as HVAC calculations.

The purpose of this paper is to carry out a hydrodynamic and thermal analysis of turbulent forced-convection flows of pure water, pure ethylene glycol and water-ethylene glycol mixture, as base fluids dispersed by Al₂O₃ nano-sized solid particles, through a constant temperature-surfaced rectangular cross-section channel with detached and attached obstacles, using a computational fluid dynamics (CFD) technique. Effects of various base fluids and different Al₂O₃ nano-sized solid particle solid volume fractions with Reynolds numbers ranging from 5,000 to 50,000 were analyzed. The contour plots of dynamic pressure, stream-function, velocity-magnitude, axial velocity, transverse velocity, turbulent intensity, turbulent kinetic energy, turbulent viscosity and temperature fields, the axial velocity profiles, the local and average Nusselt numbers, as well as the local and average coefficients of skin friction, were obtained and investigated numerically.

The fluid flow and temperature fields were simulated using the Commercial CFD Software FLUENT. The same package included a preprocessor GAMBIT which was used to create the mesh needed for the solver. The RANS equations, along with the standard k-epsilon turbulence model and the energy equation were used to control the channel flow model. All the equations were discretized by the finite volume method using a two-dimensional formulation, using the semi-implicit method for pressure-linked equations pressure-velocity coupling algorithm. With regard to the flow characteristics, the interpolation QUICK scheme was applied, and a second-order upwind scheme was used for the pressure terms. The under-relaxation was changed between the values 0.3 and 1.0 to control the update of the computed variables at each iteration. Moreover, various grid systems were tested to analyze the effect of the grid size on the numerical solution. Then, the solutions are said to be converging when the normalized residuals are smaller than 10-12 and 10-9 for the energy equation and the other variables, respectively. The equations were iterated by the solver till it reached the needed residuals or when it stabilized at a fixed value.

The result analysis showed that the pure ethylene glycol with Al₂O₃ nanoparticles showed a significant heat transfer enhancement, in terms of local and average Nusselt numbers, compared with other pure or mixed fluid-based nanofluids, with low-pressure losses in terms of local and average skin friction coefficients.

The present research ended up at interesting results which constitute a valuable contribution to the improvement of the knowledge basis of professional work through research related to turbulent flow forced-convection within channels supplied with obstacles, and especially inside heat exchangers and solar flat plate collectors.

To study the hydrodynamic and thermal behaviors of a turbulent flow of nanofluids, which are composed of saturated water and Al₂O₃ nanoparticles at various concentrations, flowing inside a tube submitted to a uniform wall heat flux boundary condition.

A numerical method based on the “control‐volume” approach was used to solve the system of non‐linear and coupled governing equations. The classical κ‐ε model was employed in order to model the turbulence, together with staggered non‐uniform grid system. The computer model, satisfactorily validated, was used to perform an extended parametric study covering wide ranges of the governing parameters. Information regarding the hydrodynamic and thermal behaviors of nanofluid flow are presented.

Numerical results show that the inclusion of nanoparticles into the base fluid has produced an augmentation of the heat transfer coefficient, which has been found to increase appreciably with an increase of particles volume concentration. Such beneficial effect appears to be more pronounced for flows with moderate to high Reynolds number. In reverse, the presence of nanoparticles has induced a rather drastic effect on the wall shear stress that has also been found to increase with the particle loading. A new correlation, Nu_fd=0.085 Re^0.71 Pr^0.35, is proposed to calculate the fully‐developed heat transfer coefficient for the nanofluid considered.

This study has provided an interesting insight into the nanofluid thermal behaviors in the context of a confined tube flow. The results found can be easily exploited for various practical heat transfer and thermal applications.

The present study is believed to be an interesting and original contribution to the knowledge of the nanofluid thermal behaviors.

The purpose of this paper is to present some methods to analyse and determine the performance of compact heat exchangers; show the applicability of various computational approaches and their limitations, provide examples to demonstrate the methods, and present results to highlight the opportunities and limitations of the considered methods.

Engineering methods based on thermal balances and correlations, as well as computational fluid dynamics (CFD) methods based on the finite control volume (CV) approach, are used.

Overall, it is found that computational heat transfer methods of various kind and complexity are useful tools if carefully handled and appropriately applied. However, there are several constraints, difficulties and limitations to be aware of. Radiators, extended surfaces and enhanced ducts are considered.

The paper presents a timely and coherent review and description of various computational methods to simulate the thermal‐hydraulic performance of compact heat exchanger issues.

To understand and analyze sanctions evasion and enforcement via virtual currencies.

Discusses various jurisdictions’ attempts to further the use of virtual currency to facilitate and maximize access to international funds; analyzes the aspects that make virtual currency uniquely suited to evade sanctions; suggests best practices for industry participants to be sure to account for the differences in crypto asset structure and related risks.

The US Treasury Department’s Office of Foreign Assets Control (OFAC) has explicitly stated that despite virtual currency’s anonymity, industry participants are still responsible for policing and enforcing client compliance. Although sanctioned jurisdictions are thinking creatively about ways around SWIFT, the use of virtual currency to skirt sanctions presents certain challenges.

Virtual currency industry participants should understand OFAC’s specific guidance regarding compliance obligations in the cryptocurrency space, and should implement best practices and conservative measures to avoid unknowingly running afoul of sanctions laws.

Expert analysis and guidance from experienced investigations and sanctions lawyers.

The purpose of this paper is to optimize the performance of an incinerator plant in terms of NO emissions and temperature of particles 2 s after the last air injection, which must be above 850°C as established from the Directive 2000/76/EC of the European Parliament and of the Council – December 4, 2000 on dioxins formation in waste incineration plants.

Investigation is made by coupling proper models developed within three commercial software environments: FLUENT, to reproduce the thermodynamic field inside the combustion chamber of the incinerator plant taken into account, MATLAB, to evaluate the position and temperatures of the particles 2 s after the last air injection, MODEFRONTIER, to change both the secondary air mass flow rate and the equivalent heat transfer coefficient of the refractory walls to fulfill the conflicting objectives of reducing the NO formation and increasing the mean gases temperature as required by the Directive.

The investigations suggest that it is possible to create the conditions allowing the reduction of NO emissions and the fulfilment of the European limits. In particular, the obtained results suggest that increasing the overall mass flow rate of the secondary air and using a different refractory material on the walls, the environmental performance of the incinerator plant can be improved.

Many other parameters could be optimized and, at the same time, more detailed models could be used for the Computational Fluid Dynamics simulations. Moreover, also the energy generated at the plant would need a better investigation in order to understand if optimal conditions can be really achieved.

The work covers new aspects of Waste-to-Energy (WtE) systems, since it deals with an optimization study of plant design and operating parameters. This kind of investigation allows not only to improve already existing technologies for WtE systems, but also to develop new ones.

To determine the axial evolution of the hydrodynamic and the thermal fields for mixed convection in inclined tubes and to investigate the presence of flow reversal.

The elliptical, coupled, steady state, three‐dimensional governing partial differential equations for heated ascending laminar mixed convection in an inclined isothermal tube were solved numerically using a finite volume staggered grid approach.

The axial evolution of the velocity profiles and fluid temperatures show that upstream diffusion has an important effect near the inlet of the heating region. As a result, both the wall shear stress and the Nusselt number are affected upstream of the heating zone. Flow reversal occurs of GF≥9 × 10⁵. The shape and size of the region with negative velocities depends strongly on the value of the Grashof number. The effect of the Grashof number on the axial evolution of the wall shear stress and the Nusselt number is shown to be very important in the region of developing flow.

The results have been calculated for one Reynolds number (Re=100), a single fluid (air) and one tube inclination (45°).

Further results of this type can be mapped and would be useful for heat exchanger design.

This is the first time that flow reversal has been calculated numerically for inclined tubes. Most previous studies concern horizontal or vertical tubes and use axially parabolic equations which are easier to solve but can not calculate the flow field in the region with backflow.