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Vertical gardens offer multiple benefits in urban environments, including passive cooling services. Previous research explored the use of “active vertical gardens” as potential evaporative air-cooling units by developing a mathematical model based on the FAO-56 Penman Monteith equation. Further research showed that active vertical gardens function best by creating an airflow in the cavity behind the garden such that air is cooled by flowing over the water-saturated garden substrate. The purpose of this paper is to improve the quantification of active vertical garden performance.

A building-incorporated vertical garden was built in Quito, Ecuador, with an air inlet at the top of the garden, an air cavity behind the garden and where air was expelled from the base. Measurements were made of air temperature, humidity and velocity at the air inlet and outlet.

The active vertical garden cooled the air by an average of 8.1 °C with an average cooling capacity of 682.8 W. Including the effects of pre-cooling at the garden inlet, the garden cooled the air by an average of 14.3 °C with an average cooling capacity of 1,203.2 W.

The results are promising and support the potential for active vertical gardens to be incorporated into building services and climate control.

The purpose of the study is to optimise the cross-sectional shape of passively cooled horizontally mounted pin-fin heat sink for higher cooling performance and lower material usage.

Multi-objective shape optimisation technique is used to design the heat sink fins. Non-dominated sorting genetic algorithm (NSGA-II) is combined with a geometric module to develop the shape optimiser. High-fidelity computational fluid dynamics (CFD) is used to evaluate the design objectives. Separate optimisations are carried out to design the shape of bottom row fins and middle row fins of a pin-fin heat sink. Finally, a computational validation was conducted by generating a three-dimensional pin-fin heat sink using optimised fin cross sections and comparing its performance against the circular pin-fin heat sink with the same inter-fin spacing value.

Heat sink with optimised fin cross sections has 1.6% higher cooling effectiveness than circular pin-fin heat sink of same material volume, and has 10.3% higher cooling effectiveness than the pin-fin heat sink of same characteristics fin dimension. The special geometric features of optimised fins that resulted in superior performance are highlighted. Further, Pareto-optimal fronts for this multi-objective optimisation problem are obtained for different fin design scenarios.

For the first time, passively cooled heat sink’s cross-sectional shapes are optimised for different spatial arrangements, using NSGA-II-based shape optimiser, which makes use of CFD solver to evaluate the design objectives. The optimised, high-performance shapes will find direct application to cool power electronic equipment.

This paper presents possibility of laser application for fabrication of 3D elements and structures. The Aurel NAVS‐30 Laser Trimming and Cutting System with special software was used. It was applied successfully for fabrication of vias (minimum diameter – 50 μm) in fired and unfired LTCC ceramics and channels with width between 100 μm and 5 mm. The achievements and problems are presented and discussed. The influence of lamination process on quality of vias and channels as well as the problems connected with interaction of laser beam with ceramic tapes are shown. Three‐dimensional resistors and microfluidic system were successfully designed and fabricated based on our investigations. Chosen electrical and thermal parameters of constructed devices are shown, too.

This paper aims to investigate vulnerability factors that influence thermal comfort in residential buildings in the context of climate change and variability, as well as adaptive strategies that can be adopted. There is a need for research that systematically addresses factors influencing thermal comfort in the context of climate change.

Using a vulnerability framework, this paper reviews existing literature to identify factors driving impacts to comfort, as well as strategies to increase adaptive capacity in buildings. Data were collected from several sources including international organizations, scientific journals and government authorities, following an initial Web-based subject search using Boolean operators.

Significant impacts can be expected in terms of thermal comfort inside buildings depending on four vulnerability factors: location; age and form; construction fabric and occupancy and behaviour. Despite the fact that the majority of the existing studies are technically driven and spatially restricted, there is strong evidence of interdependencies of scales in managing vulnerability and adaptive capacity.

Results from this review emphasise the importance of balance mitigation with adaptation regarding new building design and when retrofitting old buildings. The factors identified here can also be used to assist in construction of simplified tools such as a vulnerability index that helps in identifying the most vulnerable buildings and dwellings and assist in retrofit decisions.

The paper offers critical insight regarding implications in building design and policy in a vulnerability framework.

The purpose of this study is to quantify the free convective heat transfer around a vertical cylindrical electronic component equipped with vertical fins representing an antenna, contained in a closed cavity maintained isothermal. Its cooling is provided via a water-based copper nanofluid whose volume fraction varies between 0% and 10%. Its effective viscosity and thermal conductivity are determined with the Brinkman and Maxwell models.

The governing equation system has been solved by means of the volume control method based on the SIMPLE algorithm.

A Nusselt-Rayleigh correlation valid in the 3.32 × 10⁵ – 6.74 × 10⁷ Rayleigh number range is proposed. It allows the thermal sizing of the considered system used in high power electronics to ensure their correct operation in the worst conditions.

The proposed correlations are original and unpublished.

The purpose of this paper is to compare the thermal effect between square and circular geometry of light emitting diode (LED) with respect of the same surface for the intent of reducing the junction temperature.

The heat equation is presented in a dimensionless form. To solve it numerically subject to the boundary conditions, the authors realized a three-dimensional code with Comsol Multiphysics.

The model is validated with previously published works. The authors found a good agreement.

New design of heat sink is improved for circular LED and a reduction of 18 per cent of the junction temperature is permitted. The authors study the influence of various parameters: number and length of fins and number and width of splits. New distribution of multichip LED in circular geometry permits to put 42 chips instead of 36 chips with respect of the same surface and pitch and with reduction of the junction temperature by 16 per cent.

The purpose of this study is to investigate the validation of the usefulness of cooling systems containing Peltier modules for cooling power devices based on measurements of the influence of selected factors on the value of thermal resistance of such a cooling system.

A cooling system containing a heat-sink, a Peltier module and a fan was built by the authors and the measurements of temperatures and thermal resistance in various supply conditions of the Peltier module and the fan were carried out and discussed.

Conclusions from the research carried out answer the question if the use of Peltier modules in active cooling systems provides any benefits comparing with cooling systems containing just passive heat-sinks or conventional active heat-sinks constructed of a heat-sink and a fan.

The research carried out is the preliminary stage to asses if a compact thermal model of the investigated cooling system can be formulated.

In the paper, the original results of measurements and calculations of parameters of a cooling system containing a Peltier module and an active heat-sink are presented and discussed. An influence of power dissipated in the components of the cooling system on its efficiency is investigated.

This paper aims to present the design and experimental tests of an active circulating cooling system for the Experimental Advanced Superconducting Tokamak in-vessel inspection manipulator, which will help the current manipulator prototype to achieve a full-scale in-vessel high temperature environment compatibility.

The high-temperature effects and heat transfer conditions of the manipulator under in-vessel environment were analyzed. An active circulating cooling system was designed and implemented on the manipulator prototype. A simulative in-vessel inspection task in a high temperature environment of 100°C was carried out to evaluate the performance of the active circulating cooling system.

The proposed active circulating cooling system was proved effective in helping the manipulator prototype to achieve its basic in-vessel inspection capability in a high temperature environment. The active circulating cooling system performance can be further improved considering the cooling structure coefficient differences in different manipulator parts.

For the first time, the active circulating cooling system was implemented and tested on a full-scale of the in-vessel inspection manipulator. The experimental data of the temperature distribution inside the manipulator and the operating status of the circulating system were helpful to evaluate the current active circulating cooling system design and provided effective guidance for improving the overall system performance.

The purpose of this study is to analyze the question “In what order of magnitude does the comfort and performance improvement lie with the use of a cooling vest for construction workers?”.

The use of personal cooling systems, in the form of cooling vests, is not only intended to reduce the heat load, in order to prevent disruption of the thermoregulation system of the body, but also to improve work performance. A calculation study was carried out on the basis of four validated mathematical models, namely a cooling vest model, a thermophysiological human model, a dynamic thermal sensation model and a performance loss model for construction workers.

The use of a cooling vest has a significant beneficial effect on the thermal sensation and the loss of performance, depending on the thermal load on the body.

Each cooling vest can be characterized on the basis of the maximum cooling power (Pmax; in W/m²), the cooling capacity (Auc; in Wh/m2) and the time (tc; in minutes) after which the cooling power is negligible. In order to objectively compare cooling vests, a (preferably International and/or European) standard/guideline must be compiled to determine the cooling power and the cooling capacity of cooling vests.

It is recommended to implement the use of cooling vests in the construction process so that employees can use them if necessary or desired.

Climate change, resulting in global warming, is one of the biggest problems of present times. Rising outdoor temperatures will continue in the 21st century, with a greater frequency and duration of heat waves. Some regions of the world are more affected than others. Europe is one of the regions of the world where rising global temperatures will adversely affect public health, especially that of the labor force, resulting in a decline in labor productivity. It will be clear that in many situations air conditioning is not an option because it does not provide sufficient cooling or it is a very expensive investment; for example, in the situation of construction work. In such a situation, personal cooling systems, such as cooling vests, can be an efficient and financially attractive solution to the problem of discomfort and heat stress.

The value of the study lies in the link between four validated mathematical models, namely a cooling vest model, a thermophysiological human model, a dynamic thermal sensation model and a performance loss model for construction workers.

First responders are specialty teams who are trained to work in toxic environments to assess and diffuse the threat. They have to wear specially designed Personal Protective Ensembles (PPE) that is impermeable to liquids and gasses. Microclimate inside PPEs gets hot and humid, rapidly rendering it uncomfortable and often hazardous to work longer than 30 minutes at a time. Providing active cooling is one way to extend the time spent in PPEs. Two water-cooled prototype garments were developed at our department. This study focused on the evaluation of the prototype cooling garments using human subjects, performing simulated tasks in an environmental chamber. Both physiological and perceptual responses were considered to understand the garment's effectiveness in providing cooling relief as well as the user acceptance in terms of ease of use, comfort and perceived effectiveness. The subjects' perception of cooling relief generally agreed with the physiological data. The two prototype cooling vests positively affected skin temperatures, sweat rate, microclimate temperature, humidity, perceived temperature and perceived humidity. Both physiological and perception data indicated there were no significant and consistent differences between the two cooling vests. The subjects perceived the prototype cooling garments to provide effective cooling, to be attractive and practical overall.