Dario De Marinis, Marco Donato de Tullio, Michele Napolitano and Giuseppe Pascazio
The purpose of this paper is to provide the current state of the art in the development of a computer code combining an immersed boundary method with a conjugate heat transfer…
Abstract
Purpose
The purpose of this paper is to provide the current state of the art in the development of a computer code combining an immersed boundary method with a conjugate heat transfer (CHT) approach, including some new findings. In particular, various treatments of the fluid-solid-interface conditions are compared in order to determine the most accurate one. Most importantly, the method is capable of computing a challenging three dimensional compressible turbulent flow past an air cooled turbine vane.
Design/methodology/approach
The unsteady Reynolds-averaged Navier–Stokes (URANS) equations are solved within the fluid domain, whereas the heat conduction equation is solved within the solid one, using the same spatial discretization and time-marching scheme. At the interface boundary, the temperatures and heat fluxes within the fluid and the solid are set to be equal using three different approximations.
Findings
This work provides an accurate and efficient code for solving three dimensional CHT problems, such as the flow through an air cooled gas turbine cascade, using a coupled immersed boundary (IB) CHT methodology. A one-to-one comparison of three different interface-condition approximations has shown that the two multidimensional ones are slightly superior to the early treatment based on a single direction and that the one based on a least square reconstruction of the solution near the IB minimizes the oscillations caused by the Cartesian grid. This last reconstruction is then used to compute a compressible turbulent flow of industrial interest, namely, that through an air cooled gas turbine cascade. Another interesting finding is that the very promising approach based on wall functions does not combine favourably with the interface conditions for the temperature and the heat flux. Therefore, current and future work aims at developing and testing appropriate temperature wall functions, in order to further improve the accuracy – for a given grid – or the efficiency – for a given accuracy – of the proposed methodology.
Originality/value
An accurate and efficient IB CHT method, using a state of the art URANS parallel solver, has been developed and tested. In particular, a detailed study has elucidated the influence of different interface treatments of the fluid-solid boundary upon the accuracy of the computations. Last but not least, the method has been applied with success to solve the well-known CHT problem of compressible turbulent flow past the C3X turbine guide vane.
Details
Keywords
Klára Rybenská, Lenka Knapová, Kamil Janiš, Jitka Kühnová, Richard Cimler and Steriani Elavsky
A wide gap exists between the innovation and development of self-monitoring, analysis and reporting technology (SMART) technologies and the actual adoption by older adults or…
Abstract
Purpose
A wide gap exists between the innovation and development of self-monitoring, analysis and reporting technology (SMART) technologies and the actual adoption by older adults or those caring for them. This paper aims to increase awareness of available technologies and describes their suitability for older adults with different needs. SMART technologies are intelligent devices and systems that enable autonomous monitoring of their status, data analysis or direct feedback provision.
Design/methodology/approach
This is a scoping review of SMART technologies used and marketed to older adults or for providing care.
Findings
Five categories of SMART technologies were identified: (1) wearable technologies and smart tools of daily living; (2) noninvasive/unobtrusive technology (i.e. passive technologies monitoring the environment, health and behavior); (3) complex SMART systems; (4) interactive technologies; (5) assistive and rehabilitation devices. Technologies were then linked with needs related to everyday practical tasks (mainly applications supporting autonomous, independent living), social and emotional support, health monitoring/managing and compensatory assistance rehabilitation.
Research limitations/implications
When developing, testing or implementing technologies for older adults, researchers should clearly identify concrete needs these technologies help meet to underscore their usefulness.
Practical implications
Older adults and caregivers should weigh the pros and cons of different technologies and consider the key needs of older adults before investing in any tech solution.
Social implications
SMART technologies meeting older adult needs help support both independent, autonomous life for as long as possible as well as aiding in the transition to assisted or institutionalized care.
Originality/value
This is the first review to explicitly link existing SMART technologies with the concrete needs of older adults, serving as a useful guide for both older adults and caregivers in terms of available technology solutions.