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This article presents experimental and numerical determinations of thermal transmittance performed on three different types of window frames (vinyl, aluminium, and wooden) within the same insulated glass unit. Good agreement between experimental and numerical results was attained. Using the numerical models, thermal improvement techniques of the frames and their influence on thermal transmittance of frames were studied. The first thermal improvement technique was using the insulation materials inserted inside large air cavities. By filling the cavity of vinyl frame with the polyurethane foam, thermal transmittance of vinyl frame was lowered by 10%. The second technique was based on repeating the procedure with materials installed inside frames with the materials that have lower thermal conductivity. This technique can be applied on thermal breaks and on steel profiles inside cavities. The result of this thermal improvement (attained by replacing thermal break material with material that has lower thermal conductivity) was certain reduction of the thermal transmittance of frames, by 9%. Using stainless steel instead of the oxidized steel was reduction of the thermal transmittance of vinyl frame by 3%. For the case of wooden frames the influence of shifting glazing unit deeper into profile upon the thermal transmittance of the frame was analyzed. Installing the glass unit by 5 mm deeper into the wooden frame reduced glass thermal transmittance by 5%.

The article presents ways to choose effective structural and technological solutions for fastened thermal insulation systems of complex forms of facades based on the simulation of heat fields and flows through the use of the SolidWorks Simulation Xpress software package. Determination of the optimal parameters of thermal insulation at the design stage will allow us to get rid of the negative effects of cold bridges at the junctions of the balconies, and reduce the cost of installing bonded thermal insulation of facades with complex shapes. It was found that it is most effective to insulate not the entire contour of the balcony slab, as required by regulatory documentation, but rather the size of the insulation from the wall outside equal to 750 mm with a thickness of insulation on top of the slab of 30 mm, and on the bottom of the slab - 50 mm. It is economically feasible to use such a warming technology for modern multi-storey buildings with non-standard volumetric-architectural solutions that are built according to frame-stone, frame-monolithic or monolithic schemes without thermal break between the balcony slab and the monolithic floor slab with open types of balconies and bay windows or not closed loggias .

Modern masonry structures, apart from having a load-bearing function, are more and more subjected to additional non-structural requirements related to, e.g., thermal insulation and moisture control. This has respectively led to the introduction of thermal break layers, in practice often executed using autoclaved aerated concrete (AAC) blocks, and damp proof courses (DPC) in masonry walls. These modifications have an impact on the mechanical characteristics of the masonry, such as the shear strength. In this paper, an extensive experimental campaign is therefore conducted on masonry triplets to investigate the initial shear strength of concrete block and clay brick masonry, including AAC blocks. The impact of the the presence of a polyethylene DPC layer is also studied. Moreover, the position of the DPC membrane is varied, i.e., directly on top of the brick (which is generally not recommended yet common in construction practice) and in the middle of the mortar joint. In total, 138 shear tests were performed according to the EN 1052-3 standard, with low to moderate precompression levels. The test results focus on the differences in friction angle, shear modulus, and friction coefficient. It is concluded that the presence of an AAC block decreases the initial shear strength to a value which is lower than the one assumed by Eurocode 6. Moreover, when adding a DPC membrane, the shear strength is reduced even further to almost zero, in particular when the membrane is not put in the middle of the mortar joint.

Since energy efficiency has become the main priority in the design of buildings, load-bearing walls in modern masonry constructions nowadays include thermal break elements at the floor–wall junction to mitigate thermal bridges. The structural stability of these bearing walls is consequently affected. In the present paper, a numerical study of the resistance and stability of such composite masonry walls, including AAC thermal break layers, is presented. A finite element mesoscopic model is successfully calibrated with respect to recent experimental results at small and medium scale, in terms of resistance and stiffness under vertical load with or without eccentricity. The model is then used to extend the numerical models to larger-scale masonry walls made of composite masonry, with the aim of investigating the consequences of thermal elements on global resistance and stability. The results confirm that the resistance of composite walls is governed by the masonry layer with the lowest resistance value, except for walls with very large slenderness and loaded eccentrically: composite walls with low slenderness or loaded by a vertical load with limited eccentricities are failing due to the crushing of the AAC layer, while the walls characterized by large slenderness ratios and loaded eccentrically tend to experience buckling failure in the main clay masonry layer.

An experimental research on the resistance of composite masonry walls is presented. The composite specimens considered herein are load-bearing masonry walls comprising two types of masonry units (i.e. regular masonry units with one layer of thermal break elements). The focus regarding the thermal elements has been put on isolation layers made of aerated autoclaved concrete (AAC). The research included extensive laboratory experiments on small and medium scale of homogeneous and composite specimens (stacked blocks and masonry wallets) under uniaxial compression load with and without eccentricity. The experimental results show that the interaction between masonry and thermal elements has a positive influence on the local bearing resistance of the thermal break layer because of the stiffening brought by the upper masonry layers. Based on this observation, interaction factors are proposed. In addition, results indicate that the global strength reduction due to eccentricity showed to be slightly more severe for composite walls in comparison with the homogeneous specimens.

This paper focuses on the development of the water-cooled divertor target concept known as Thermal Break, which was carried out in two phases. In Phase 1, six small scale mock-ups were fabricated and subjected to high heat flux (HHF) testing of up to 25 MW/m2 and thermal cycling of up to 500 cycles at 20 MW/m2. All six mock-ups survived the campaign and maintained 20 MW/m2 heat exhaust capability. Detailed examination of mock-ups was carried out to understand the damage mechanisms. One mock-up, which was tested beyond its design intent at 500 cycles, shows signs of progressive damage. Potential damage modes were identified and influenced subsequent Phase 2 mock-up design. Although there are signs of tungsten surface cracking, the predominant damage mode is not by “deep cracking” but substantial permanent deformation in the interlayer features. Therefore, in Phase 2 the manufacturing procedure was updated, the interlayer grooves were given stress-relieving radii which have significantly reduced the interlayer plastic strain range. Interlayer design parameters were selected following the use of response surface-based design search and optimization. Mock-ups of the Phase 2 design have been manufactured and HHF testing is planned within 2018.

Innovations occur in the design of structural elements in order to incorporate and/or improve technical features. This study begins with a standard design for one-way reinforced pre-slabs. Thermal performance is analyzed, along with the possibility of improving it, by means of incorporating corrugated cardboard. Tests were conducted with prototypes to investigate the viability of integrating corrugated cardboard into the production process of reinforced concrete pre-slabs. The modified production processes (of corrugated cardboard and concrete pre-slabs) and the improvements in thermal performance were evident in the final design. These improvements as compared to the conventional design are quantified by thermal transmittance, which was between 90.16 and 140.98% when utilizing corrugated cardboard with a thermal conductivity between 0.10 and 0.05 W m−1 K−1 respectively. Adding this new material and modifying the resistance section did entail an increase in cost. However, the joint evaluation of the production and use phases of the structural element designed indicated a positive economic balance. It was found that with the new design, the structural solution's thermal performance improved and compensated for the increase in costs incurred during the production phase.

Virtual engineering is being widely adopted in diverse technical fields and has the potential to accelerate the realization of tokamak fusion energy. In this paper, we demonstrate, for the first time, the use of virtual engineering techniques to enhance the development cycle of a water-cooled divertor plasma facing component. The divertor concept under development is the thermal break, which aims to increase heat flux limits and DEMO-relevance by alleviating the high thermal mismatch stress between a tungsten monoblock and a copper alloy cooling pipe. Response surface-based design search and optimization is used to explore the potential of the concept and to inform the design of a high-heat-flux (HHF) mock-up. In developing a brazing manufacturing procedure, computed tomography scanning and subsequent image-based finite-element modeling revealed a defective joining process which would result in unacceptable divertor performance. The same techniques were used to develop an improved brazing procedure that was used to manufacture the mock-ups. A production defect was discovered by ultrasonic qualification testing, but a “virtual twin” model confirmed the acceptable performance of the mock-up under HHF. Indeed, all mock-ups were then subjected to at least 100 cycles of 20 MW/m 2 HHF testing, with no signs of damage. The development of these virtual engineering and modeling techniques will facilitate criteria for design and component rejection, and in future enable predictive maintenance of components in service. Practical trials and experiments will remain essential to complement and validate simulations.

This paper presents numerical and experimental investigations on a typical thermal break composite facade profile under four-point bending. The purpose of this study is to gain the knowledge of the interfacial behaviour between aluminum extrusion and polyamide insert beyond elastic range. Understanding the behaviour of this energy efficient facade profile within plastic range is important for the design under extreme loading, such as earthquakes, strong wind conditions and even blast loads. The experimental investigation was carried out on four types of beam specimens. The specimens were grouped by their span lengths with three specimens for each span length. As the specimens’ geometry and composite action are complicated, seven strain gauges were used per specimen including small strain gauges to fit in the limited space of the thermal break section. A three stage failure process was observed during the experiments. A numerical investigation was carried out by using Finite Element modelling to simulate behaviour of the thermal break composite facade profile under similar loading condition in order to compare with the testing results as well as to capture the corresponding failure mechanisms. Numerical simulations were setup by applying a proposed partitioned multi-phase failure model to simulate three stage failure process discovered by experiments. The results from FE models were compared and discussed with experimental counterparts. In summary, FE models showed consistent results to the experimental counterparts and it also provided the insight and more details of failure mechanism and stress distribution including interfacial condition details. Behaviour of the thermal break facade profile in the plastic range displayed excellent ductility and high strength capacity of this type of thermal break section in the plastic range after slip.

International audience; For buildings designed with internal insulation, thermal bridges at the junction between slabs and walls are a common issue, since they create heat loss from inside of the building. Thermal break systems (TBS), which are composed of structural elements (rebars and steel profiles) and insulation material, are used to reduce this heat loss and to transfer shear forces from the slab to the walls. Insulation system of TBS generates a temperature gap from wall to slab. As a consequence, while the wall is exposed to climatic actions and is repeatedly dilated and contracted, whereas the slab pertains a constant temperature and does not present any volumetric variation, thus the TBSs are submitted to large displacement constrains. The paper illustrates the effect of the thermal dilatation and contraction of the walls, which create a supplemental force in the TBSs, and consequently cracking of the walls. A numerical model of a quarter of a building’s storey is submitted to the climatic actions computed at the location of Embrun city, in France. One side of the L-shape wall is supposed to face to the south, and the other one to the west. The thermal and mechanical analysis are performed with the software CASTEM. In thermal analysis, air temperature and flux of solar radiation signal are defined from databases of METEO FRANCE, and are applied on the exterior surface of the walls. The results of the first calculation, by thermo-hydro-mechanical analysis (THM) with elasticity behavior, confirm that a significant stress level in tension occurs in the concrete at the corner of the walls and the nearby interface elements of the TBS. Furthermore, the TBSs that are close to the corner of the walls pertain the highest horizontal and axial forces, and are at risk to exceed the limit strength. Based on those results, a second calculation, which includes the coupling of damage with shrinkage and creep model from the THM analysis, is made for determining more realistic forces in the TBSs, and analyzing the cracking pattern of the walls. © 2021, Scipedia S.L.. All rights reserved.

[EN] The slim-floor beam is a composite concrete-steel beam fully integrated into the floor depth that was developed at the beginning of the 1990s. This composite beam presents a very good behaviour during the fire event because most of the steel parts of the section remain protected by the concrete encasement. Indeed, in a fire event, only the bottom surface of the lower steel plate results exposed to the heat source. The use of intumescent coating or other fireproof materials is the most common way to insulate the steel beam from fire but requires an accurate application and also appropriate maintenance during its whole life cycle to ensure proper fire protection. Thus, related to this last idea, the objective of this work is to present a new slim-floor configuration which increases the insulation of the beam from fire by using a design strategy that avoids the needed for maintenance. This new beam configuration has been called "Internally Fire Protected Slim-Floor Beam" (IFP-SFB) and implies a thermal break included within the beam cross-section. This paper presents the results of a series of thermal tests applied to this innovative slim-floor type proposed by the authors and its comparison against the most commonly used slim-floor configurations. Finally, the benefits of the proposed IFP-SFB configuration are presented, resulting in up to 30-60 min of additional fire resistance time. The IFP-SFB configuration is at present right-protected and under evaluation by the Spanish Office of Patents and Trademarks with reference number P201930438., The authors would like to express their sincere gratitude to the Spanish "Ministerio de Economia y Competitividad" for the help provided through the Project BIA2015-67192-R and to the European Union through the FEDER funds. The here presented "Internally Fire Protected Slim-Floor Beam" (IFPSFB) configuration is currently right-protected and under evaluation by the Spanish Office of Patents and Trademarks with the reference number P201930438 and with publication number ES2732719 A1.

An accurate thermal characterization of the envelope components is essential to achieve a reliable evaluation of thermal behaviour and energy efficiency of buildings. In lightweight steel-framed (LSF) building components, the major thermal performance concern is related to the unwanted significant thermal bridge effects originated by the high thermal conductivity of steel. The application of thermal break (TB) strips in the steel stud flanges is one of the most currently used thermal bridge mitigation strategies. In this paper the thermal performance of ten interior LSF walls configurations are measured, using the heat flow meter (HFM) method under laboratory-controlled conditions. Three TB strips materials and three TB locations (inner, outer and both sides of steel stud) are assessed and a comparison with the thermal performance of a reference wall without TB strips is made. Regarding the TB strips materials, it was found that the best thermal performance is achieved by aerogel, which is the material that presents the lowest thermal conductivity. Considering the TB strips location, the application on both sides of steel stud shows a relative significant thermal performance increase comparatively to the application on inner or outer side, presenting these last two configurations very similar performances.

The reduction of unwanted heat losses across the buildings’ envelope is very relevant to increase energy efficiency and achieve the decarbonization goals for the building stock. Two major heat transfer mechanisms across the building envelope are conduction and radiation, being this last one very important whenever there is an air cavity. In this work, the use of aerogel thermal break (TB) strips and aluminium reflective (AR) foils are experimentally assessed to evaluate the thermal performance improvement of double-pane lightweight steel-framed (LSF) walls. The face-to-face thermal resistances were measured under laboratory-controlled conditions for sixteen LSF wall configurations. The reliability of the measurements was double-checked making use of a homogeneous XPS single panel, as well as several non-homogeneous double-pane LSF walls. The measurements allowed us to conclude that the effectiveness of the AR foil is greater than the aerogel TB strips. In fact, using an AR foil inside the air cavity of double-pane LSF walls is much more effective than using aerogel TB strips along the steel flange, since only one AR foil (inner or outer) provides a similar thermal resistance increase than two aerogel TB strips, i.e., around +0.47 m2∙K/W (+19%). However, the use of two AR foils, instead of a single one, is not effective, since the relative thermal resistance increase is only about +0.04 m2∙K/W (+2%).

International audience; During the last decade, simple solutions of thermal breaks have been developed for steel structures that consist in inserting an intermediate insulating layer (composed of PVC, plywood, elastomer, FRP...) between a bolted end-plate and a steel/concrete support. Experimental tests highlighted that failure modes under bending moment are similar to that of conventional bolted connections particularly in the tensile area, whereas the ultimate resistance decreases. For standard bolted connections loaded by a bending moment, the T-stub concept is used to model the tensile area. This model, extensively used in Eurocode 3, assumes that the end-plate is in contact with a rigid foundation or concrete/grout. T-stub can potentially be used to model the tensile area of bolted connections in presence of intermediate insulating layer. However the current model cannot be directly applied as the end-plate rests on a flexible support.and nbsp;and nbsp;In the present paper, a mechanical model is proposed to firstly model the elastic behaviour of T-stubs in contact with a flexible intermediate layer. The model relies on the Timoshenko beam theory in contact with a Winkler foundation modelling respectively the end-plate and the intermediate layer. The contact pressure dis-tribution being almost linear, simplifications are proposed in this sense. It is demonstrated that simplifications can be considered for standard material used as intermediate layer such as PVC or FRP. An analytical model is also given to calculate the ultimate resistance of T-stubs considering yielding of the intermediate layer. These results are validated by comparison to finite element analysis results performed with ANSYS code using solid and contact elements. This FE analysis highlights a clear distinction between the elastic and elasto-plastic behaviors of these T-stubs particularly concerning prying effects.

A high performing DEMO divertor target mock-up design that uses the thermal break interlayer concept is presented. The design evolved from a previous design of which six mock-ups were designed, fabricated and subjected to high heat flux testing. The new design was generated using optimisation techniques; specifically, software was developed to automatically process the design of experiments data to enable visualisation of the design space. Despite the more challenging geometric constraints of this second phase, this design performs significantly better than that of the previous phase; the strain in the interlayer, which was the dominant damage mode in the phase 1 testing, is reduced by 28%. Four mock-ups of the selected design were manufactured, all of which successfully passed a series of high heat flux testing, including 500 cycles at 20 MW/m2. Design optimisation methods are not widely utilised in fusion engineering, their potential benefits, which are demonstrated here on a plasma facing component, could be applied to many other challenging designs.

Research activities in the field of innovative fixtures are continuously aiming at increasing their thermal and optical performances to offer optimal exploitation of daylight and solar gains, providing effective climate screen, according to increasing standards for indoor comfort and energy saving. Within this work, we designed an innovative aerogel-based &ldquo, thermal break&rdquo, for window frames, so as to consistently reduce the frame conductance. Then, we compared the performance of this new frame both with currently used and obsolete frames, present in most of the existing building stock. Energy savings for heating and cooling were assessed for different locations and confirmed the potential role played by super-insulating materials in fixtures for extremely rigid climates.

Increasing building energy performance has become an obligatory objective in many countries. Thermal bridge is a major cause of poor energy performance, durability, and indoor air quality of buildings. This paper starts with a review of thermal bridges and their negative impacts on building energy efficiency. Based on published literatures, various types of building thermal bridges are discussed in this paper, including the most effective solutions to diminish their impacts. In addition, various numerical and experimental studies on the balcony thermal bridge are explored. Results show that among all types of thermal bridges, the exposed balcony slab produces the most challenging thermal bridging problem where an integrated thermal and structural design is required. Using low thermal conductivity materials in building construction could help in reducing the impact of thermal bridges. Finally, further investigations are needed to develop more innovative and effective solutions for the balcony thermal bridge.

Cladding details that span the building envelope are particularly susceptible to forming thermal bridges, where heat is transferred between interior and exterior, resulting in loss of energy. Steel buildings are particularly susceptible to forming thermal bridges due to the relatively high thermal conductivity of steel compared to that of other structural materials. To mitigate these thermal bridges, thermal breaks may be inserted in the cladding detail connection to the building interior, and have demonstrated promise in previous thermal modeling studies, with up to 65% reduction in thermal bridging. This paper summarizes recent work on the design, validation, and implementation of thermal break strategies that maintain structural integrity. Fiber-reinforced polymer (FRP) shims were used to provide thermal breaks in steel connections of cladding details. Partial replacement of steel structural members with FRP members was also explored. Shims were the focus of the work due to ease of installation, cross-section availability, and thermal performance. While several cladding details were examined in this research, this paper summarizes the cyclic performance of roof posts (under axial and cyclic lateral loads) and canopy beams (under cyclic lateral loads only), representing their anticipated performance during earthquakes and wind events. While roof posts and canopy beams exist in a range of applications in building construction, structural archetypes selected for this work represent lightly-loaded examples that are common in the field. The impact of adding FRP shims at the bolted base plate connection to the building interior is discussed. Recommendations for design and future research are also presented.

Thermal runaway is among the major failure mechanisms of power semiconductor packages. Thermal dissipation of power electronics depends on the quality of the solder die-attach, any defects such as voids, and delamination-impede heat dissipation that results in hot spots that can cause thermal runaway and/or a premature device failure. Therefore, investigation of thermal impact due to die-attach defects is indispensable for improved device performance and reliability. In this paper, transient dual interface measurement is used to characterize the thermal path of a power electronic package consisting of an insulated gate bipolar transistor (IGBT) and copack diode. The die-attach defects were identified by X-ray imaging. The impact of voids on thermal dissipation was quantified by junction-to-case thermal resistance and structure function analysis. The junction-to-case thermal resistance (IGBT) values were found to be increasing with the increase in void%. The largest void% instead of the total void% has a greater impact on the thermal dissipation of the devices. However, die-attach voids under the IGBT die have no impact on junction-to-case thermal resistance (diode), suggesting that the copack diode heat path is independent of the IGBT heat path.

Although the air-conditioning intermittent operation is widely used in buildings, more attention is focused on the air-conditioning continuous operation in the whole building to simplify energy conservation design, and thereby, the operation method inconsistence of air-conditioning must lead to the large difference between actual value and design value of energy consumption. According to this situation, in order to explore the wall energy conservation difference under the continuous and intermittent operation of air-conditioning, a experiment is built to analyze the effect of the thermal insulation layer location on wall dynamic thermal response rate. Experimental result shows that under the air-conditioning intermittent operation, wall cold storage is the main source of air-conditioning load formed by walls and the wall internal layer has the significant effect on the wall dynamic thermal response performance. And the closer to wall inner surface for the thermal insulation layer, the lower the inner surface temperature and the higher the wall thermal response rate. Meanwhile, the internal thermal insulation wall has the smallest heat flow value, which is less 35–86% than external thermal insulation wall and the sandwich thermal insulation wall, although they have the same heat transfer coefficients.

WO3 was evaluated as a candidate thermal barrier oxide material for protection of thermally sensitive systems (e.g., electronics packages) exposed to thermal cycling between −51 and 71 °C. A key factor for thermal barrier oxides is low thermal conductivity. Thermal conductivity serves as a quantifiable metric for assessing the thermal shielding/insulation behavior of a material. This paper assesses structural and phase effects on the thermal properties of WO3. Results suggest that the thermal conduction behavior of WO3 powders is driven by crystal/grain packing and in the temperature range of interest.

Thermal bridging caused by exposed concrete balcony slab is a major source of heat loss through energy efficient building envelopes. Moreover, thermal bridging can also create moisture management and indoor comfort challenges. Numerous investigations have been carried out to reduce heat transmittance through exterior building envelopes and minimize the energy use in buildings. The most effective way to minimize heat transmittance of exposed concrete balcony slabs is to thermally separate the exterior structure from the interior structure using thermal breaks. To enhance thermal separation, this paper investigates the effects of replacing high conductive materials such as reinforced concrete or structural steel with a multilayer composition of high-performance hybrid insulating systems. Reinforcing bars, such as fiber reinforced plastics (FRPs), having lower thermal conductivity than steel are used to connect interior to exterior and transfer loads. Numerical simulation tool THERM is used to study the effects of thermal breaks on energy performance of the concrete slab balcony joints. Simulation results indicate significant thermal performance improvement while high-performance hybrid insulating systems were used for exposed concrete balcony slab constructions, compared to traditional insulating systems used in similar constructions

Thermal Energy Storage systems using inorganic salts as Phase Change Materials (PCM) are ideal solutions for solar thermal direct steam generation power plants. However, the main limitation of these PCM is their low thermal conductivity. Though a composite PCM solution including graphite foam will increase the effective thermal conductivity of the storage material, the system performance is limited by the thermal contact resistance at the heat exchanger surface. An infiltrated PCM (sodium nitrate, NaNO3) in different commercial graphite foam structures, with variable porosity and apparent density is analyzed experimentally and numerically. The thermal properties of the PCM and the graphite matrix are experimentally determined to calculate effective properties of the composite. The performance of the composite PCM-graphite foam in a heat exchanger with embedded metallic tubes is analyzed for each foam type. During system operation, the difference in thermal expansion coefficients between the composite PCM and metallic tubes creates a void at the interface, which is gradually filled by the liquid salt. The effect on the discharge process of this low thermal conductivity layer forming around the steel tube is evaluated numerically, analyzing the deviation from the expected thermal performance of the ideal system.

The paper presents the model of construction component (insulating hollow core plate) in the form of a plate made of rigid thermal insulation material, with modifications in the geometry of the section. The modifications consist of channels parallel to the longer edge of the plate with sections of simple geometrical figures. What needs to be determined is the impact of the channels with different section type and its location in the plate on the thermal insulation property of the plate. The aim of the research is to obtain a composite insulating material of low weight and low thermal conductivity coefficient, that would be similar to a solid material and that would allow for the reduction of raw materials used in its production at the same time. The authors analyze thermal parameters of the suggested thermo insulating hollow core plate solution, using 2 and 3 dimensional MES modelling, accompanied by the laboratory verification of the obtained results.

Light steel framed (LSF) construction is becoming widespread as a quick, clean and flexible construction system. However, these LSF elements need to be well designed and protected against undesired thermal bridges caused by the steel high thermal conductivity. To reduce energy consumption in buildings it is necessary to understand how heat transfer happens in all kinds of walls and their configurations, and to adequately reduce the heat loss through them by decreasing its thermal transmittance ( U -value). In this work, numerical simulations are performed to assess different setups for two kinds of LSF walls: an interior partition wall and an exterior facade wall. Several parameters were evaluated separately to measure their influence on the wall U -value, and the addition of other elements was tested (e.g., thermal break strips) with the aim of achieving better thermal performances. The simulation modeling of a LSF interior partition with thermal break strips indicated a 24% U -value reduction in comparison with the reference case of using the LSF alone ( U = 0.449 W/(m2.K)). However, when the clearance between the steel studs was simulated with only 300 mm there was a 29% increase, due to the increase of steel material within the wall structure. For exterior facade walls ( U = 0.276 W/(m2.K)), the model with 80 mm of expanded polystyrene (EPS) in the exterior thermal insulation composite system (ETICS) reduced the thermal transmittance by 19%. Moreover, when the EPS was removed the U -value increased by 79%.

This article is devoted to the issues of obtaining accurate data on the processes during a short circuit in a 0.4 kV network. These data allow determining the influence of short circuits on the electroconductive network elements and reveal the effectiveness of electrical protection. The method for solving the problem is based on determining the amount of energy needed to the wire thermal break. In order to determine it, we use the heat balance equation and substantiate the reasons for the reduction in the accuracy of calculations for techniques that are not based on the energy approach. The problem considered the behavior of an electric arc. Standard wires materials and standard methods of their installation are used while modeling. As a result, we obtain the general formula that allows calculating the time of the wire thermal break. The method is described and recommendations for its use are given.

In buildings, thermal bridging can be formed through structural components such as protruding balconies. For this reason, thermal break systems are used to limit heat flow in order to fulfi...

In this paper, a comparison is presented among the ultrasonic measures of different W-monoblock mock-ups following high heat flux tests. The DEMO reference solution for the divertor targets (ITER-like) is compared with two other concepts, in which the interlayer between monoblocks and tube has been engineered to increase the performance of the component (Thermal Break Interlayer, Thin Graded Interlayer). Ultrasonic measurements have been performed at the depths of interest. The reflected signal amplitude and time of flight at defined depths are used to determine the shape and entity of the defect, when present. For each concept, the most frequently observed defects due to thermal loading are then identified. Preliminary post-mortem analysis confirms the results from the ultrasonic tests, proving the defect imaging capability of such non-destructive technique for advanced W-monoblock concepts.