Internal Temperature Research Articles

Precise Synergistic Photothermal Therapy Guided by Accurate Temperature‐Dependent NIR‐II Fluorescence Imaging

AbstractPhotothermal therapy (PTT) is considered a promising treatment strategy for solid tumors. However, local hyperthermia (over 45°C) during PTT can cause severe side effects in neighboring healthy tissues. PTT with accurate temperature feedback is a compelling strategy to ablate tumors and reduce side effects, but it still faces challenges. Here, a new kind of phototheranostic nanoparticle, namely 17‐RF@Ag2Se is developed, enabling in vivo NIR‐II fluorescence tracking, PTT and fluorescence nanothermometry as well as synergistic heat‐shock protein (HSP) inhibition. Precise PTT with high spatiotemporal resolution is achieved with the help of the designed NIR‐II fluorescence imaging‐photothermal therapy linkage apparatus. Upon intravenous injection, 17‐RF@Ag2Se is specifically accumulated in tumors targeted by the overexpressed integrin αvβ3, which is monitored by NIR‐II fluorescence imaging of Ag2Se QDs. Further, the release of HSP inhibitor, tanespimycin (17‐AAG), enhances the thermosensitivity of tumor cells. Subsequently, the internal temperature of the tumor is precisely monitored and adjusted during PTT via the temperature‐dependent NIR‐II fluorescence feedback of Ag2Se QDs and the linkage apparatus calibration, thereby achieving efficient and safe tumor PTT. Also, the results present a new method for accurate temperature monitoring and control in vivo, which can be applied to other biomedical studies.

An approach of the internal friction-dependent temperature changes for conventional and pure biogenic lubricating greases

This work investigated the temperature changes inside the bulk of lubricating greases under controlled high-shear stress conditions (250–500 s−1). For this purpose, a newly developed temperature-measuring cell called Calidus was successfully tested. The temperature changes (ΔT) have been related to the greases’ components (thickener, base oil-type, and composition) and the structural degradation of the lubricating greases. Furthermore, a theoretical approach was proposed for calculating the internal temperature change of lubricating greases during shear stress. All greases showed an internal temperature profile characterised by a sudden rise in ΔT within the first 4 h from starting the test and subsequent ΔT decay until it reaches the steady state value. Furthermore, it was found that greases C1 and C5, formulated with lithium and calcium soap, respectively, with different soap content (16.1 wt% and 9.7 wt%, respectively), but the same base castor oil, showed the highest value of the maximum ΔT, c.a. 3.2 K, and the most drastic drop of ΔT. These greases showed both the highest specific densities and heat capacities. In addition, they showed the lowest ratio of expended energies (Rtee), which means more structural degradation in the stressed grease. On the contrary, the grease C3, with 13 wt% of Li-soap but the lowest base oil’s viscosity, showed the lowest maximum ΔT and the temperature profile was characterised by a moderate variation of ΔT along the test. The biogenic grease B3 developed a low-temperature change in the group of pure bio-genic greases close to grease C3.

LED biasing scheme with thermal compensation for automotive industry applications

This work introduces a novel scheme for driving light-emitting diodes (LEDs) with thermal compensation. The primary objective of the system is to address the issue of emitted light intensity drift caused by temperature variations, with a particular focus on the automotive industry. The developed technique proposes an alternative approach to the traditional thermal approach, which primarily focuses on heat dissipation. In contrast, the presented strategy utilizes a temperature-dependent element, such as a thermistor, to generate a reference current that increases with temperature. The generated current is then amplified by a commercial integrated driver and employed to bias the LEDs. Consequently, the reduction in the emitted light intensity resulting from an increase in the internal temperature of the LED is counterbalanced by an elevation in the bias current. The luminous flux model developed for the proposed system predicts the attainment of stable light intensity across a wide temperature range. The proposed strategy has been applied to three commercial LEDs commonly employed in automotive signal lighting to produce red, yellow, and white light. Experimental results confirm a significant reduction in the thermal dependence of the luminous flux, with reduction factor of temperature dependence ranging between 3.7 and 14.2 for the least and most temperature-sensitive LED models analyzed, respectively.

Restructured beef steaks with inclusion of digestion-resistant maltodextrin: Techno-functional characteristics, nutritional value, sensory quality, and storage stability

This study was aimed at evaluating the effects of digestion-resistant maltodextrin (DRM) inclusion, as a mean for functional dietary fiber-enrichment, on the quality and stability of precooked restructured beef steaks. The restructured steaks were prepared from ground beef by cold gelation, with alginate as binding agent, using three inclusion levels of DRM: 0 % (control), 4 % and 8 %. The products were cooked on heating plates at 180 °C until 71 °C internal temperature, vacuum-packed, stored at 4 °C, and their quality was monitored during 35 days. The inclusion of DRM resulted in improved cooking yields (76.93 ± 2.06 %, P < 0.05) and slower rates of lipid (0.47 ± 0.01 TVBN, P < 0.05) and protein degradation (1.64 ± 0.01 TBARS, P < 0.05). This fiber source did not affect the water and fat holding capacities, tenderness, microbiological quality, nor sensory acceptance of the meat products (P > 0.05); however, it influenced their color evaluated by tristimulus colorimetry (P < 0.05). The nutritional composition of the restructured steaks, including the dietary fiber content, was consistent with the level of proportional inclusion of MDR in the formulations, allowing to significantly (P < 0.01) increase their contribution to daily reference values to approximately 14 % and 27 %. According to international food labeling regulations, the products at their standard serving sizes can be classified either as good (4 % of included DRM) or superior (8 % of included DRM) sources of dietary fiber.

A novel in-tube reformer for solid oxide fuel cell for performance improvement and efficient thermal management: A numerical study based on artificial neural network and genetic algorithm

The pursuit of higher power density and compact structure presents a critical challenge to the thermal management of solid oxide fuel cell. In this study, a novel in-tube reformer is proposed and a Multi-physics simulation-Artificial neural network-Multi-objective genetic algorism based optimization framework is developed to improve the output performance and reduce the internal temperature difference in solid oxide fuel cell. First, a validated multi-physics model is developed for parametric simulation and generating dataset. Afterwards, a surrogate model is obtained by training an artificial neural network to predict the output performance and internal temperature field of solid oxide fuel cell. Finally, multi-objective genetic algorithm optimizations based on the surrogate model are performed to maximize the output performance and minimize the internal temperature difference under different operation strategies. It is found that compared to the conventional configuration (without in-tube reformer), the use of in-tube reformer can effectively promote the electrochemical reactions, increase the fuel utilization (up to 34.2%) and current density (up to 14.5%) while significantly reducing the maximum temperature difference (up to 85.5%) in the cell, resulting in a uniform current density and temperature distribution along the cell. The proposed novel in-tube reformer and optimization framework are demonstrated to be highly powerful and can be easily applied to other fuel cell/electrolyzer systems to effectively improve system performance and realize efficient thermal management under actual demands.

Internal temperature measurement of ablating bodies in high-speed flows

A novel pyranine-based luminescent temperature sensor was embedded within water ice to study heat transfer dynamics of blunt-nosed ablating bodies in supersonic and hypersonic flows. A circular half cylinder and sphere test article were created out of water ice with an embedded temperature sensitive layer to observe cross-sectional temperature profiles. The half cylinder and sphere were exposed to flow with stagnation temperatures of 700 K and 800 K at Mach 2 and Mach 7 respectively. The luminescent sensor successfully measured the amount of ablated material and the temperature profiles inside of the test articles during convective heating. The cumulative heat absorbed by the test articles as a function of time was calculated from the ablated material and the temperature rise measured from the luminescent sensor. The calculated cumulative heat was then compared to analytical estimates for convective heating of blunt-nosed bodies in high-speed flows and shown to be in good agreement.

Cellulose nanofibers based composite membrane with high solar radiation and heat conduction for agricultural thermal dissipation application

Thermal dissipation materials that can emit thermal radiation and enhance thermal conductivity are critical for agricultural thermal management and the establishment of an energy efficient society. Here, cellulose nanofibers based composite membranes are prepared by extraction, homogenization, alkali treatment, and steam modification using rice straw as raw materials for agricultural thermal management. The composite membranes not only achieve a radiative cooling effect with high solar emissivity (0.89) for outdoor thermal management but also enables a synergetic effect with high thermal conductivity (2.103 W·m−1·K−1) to reduce the internal temperature of agricultural films, which is 7.2 °C cooler than mulch films. The alkali treatment process enables the formation of hydrogen bonds between boron nitride and cellulose nanofibers, thereby significantly enhancing the composite membrane's mechanical properties. The composite membranes exhibited excellent mechanical strength due to the new hydrogen bonds between boron nitride and cellulose nanofibers. Therefore, this work provides new ideas for exploring the comprehensive utilization of agricultural waste and the working mechanism for the preparation of agricultural waste-based materials, as well as a low-carbon development path of “agriculture-environment-energy”.

Experimental study on refrigeration system performance of pure electric refrigerator car based on medium pressure air supply

In view of the low refrigeration efficiency of the refrigeration system of the pure electric logistics car under the high temperature environment, an experimental platform of the refrigeration system based on medium pressure air supply of the pure electric refrigerator car was built with R404A as the refrigerant, the experiment results show that the system refrigerating capacity, COP and EER decrease with the increase of external environment temperature under the same internal environment temperature, the compressor power and exhaust temperature increase with the increase of the external environment temperature. When the external environment temperature is 43 °C, the medium pressure air supply technology is obviously better than the non-air supply technology, the refrigerating capacity increased by 4.1–12.73 %, the compressor power and EER changed little, the COP increased by 1.3–6.38 %, and the exhaust temperature reduced by 3.4 °C-7.11 °C, especially at -3 °C, the system refrigerating capacity decreases by 30.1 %, the compressor power increases by 35.6 %, the COP and EER distribution decreases by 51.24 % and 42.68 %.

Elevated temperature properties of foam concrete: Experimental study, numerical simulation, and theoretical analysis

Foam concrete, as an inorganic cellular material possessing exceptional thermal insulation and fire resistance properties, emerges as a promising candidate for thermal insulation. To achieve a more precise evaluation of its performance under elevated temperatures, the present study comprehensively investigates the thermal characteristics of foam concrete with a combined experimental, numerical, and theoretical approach. Firstly, a high-temperature test is conducted to investigate the influence of temperature and foam concrete density on its macroscopic appearance and internal temperature distribution. Meanwhile, the thermal conductivity of foam concrete at various densities and temperatures is directly measured with a thermal conductivity analyzer. Subsequently, to acquire comprehensive specific heat and thermal conductivity parameters of foam concrete, with a numerical model established within ABAQUS, the genetic algorithm is applied to identify these thermal parameters based on the measurement data from the elevated temperature test. In addition, CT scanning and 3D reconstruction of foam concrete before and after exposure to elevated temperatures are utilized to extract pore characteristics. This facilitates the thermal conductivity calculation using theoretical models, enabling the determination of the thermal conductivity of foam concrete above 600 °C. Through a comparison of the experimental, numerical, and theoretical results, it is recommended to consider the variation of specific heat in three dehydration stages due to the observed notable dehydration. Due to the effect of cracks, the numerically determined thermal conductivity is slightly higher compared to the experimentally and theoretically determined thermal conductivity. Based on the analysis, an improved formula predicting the specific heat of foam concrete, and a formula determining the thermal conductivity of foam concrete subjected to elevated temperature are proposed.

Evaluation of Serrano Pepper Crops Growth under Controlled Conditions of Vapor Pressure Deficit in a Pilot-Scale Hydroponic Greenhouse

Controlled Environment Agriculture (CEA) has become an important field of study in recent years. The objective of this research is to evaluate the growth rate of the serrano pepper crop under controlled conditions of vapor pressure deficit in a pilot-scale hydroponic greenhouse. The controlled conditions were generated with the development of a control system composed of a non-mixed crossflow heat exchanger for internal temperature and a humidification system for internal humidity control. The comparison of variables and the growth rate of the crop was carried out in a controlled and a timed greenhouse. The best growth rate for serrano pepper cultivation was obtained under the following conditions: between 4.14 and 5.42 kPa with 0.251 and 0.225 cm/day in the controlled greenhouse. The results show that it is possible to obtain higher crop growth rates by controlling the vapor pressure deficit in a pilot-scale hydroponic greenhouse, using a heat exchanger for temperature control and a humidification control system. Controlling vapor pressure deficit can be a useful tool for agriculture in CEA.

Performance evaluation of a novel photo-thermal-electric hybrid system

Solar thermal power systems are promising electricity generation technology; however, their thermal efficiency is low due to the installed tilt angles and heat losses of solar collectors. Herein, a novel photo-thermal-electric hybrid system that integrates a tilt angle-independent and efficient evacuated U-tube solar collector with a thermally regenerative electrochemical cycle is theoretically conceptualized to evaluate its effectiveness. By developing a mathematical model, analytical expressions for performance indicators as well as the conditions delivering electricity of the hybrid system are deduced. Regardless of tilt angle, calculations indicate that the power density, energy efficiency and exergy efficiency can reach 82.99 W m−2, 8.30 % and 7.61 %, respectively. The hybrid system is less efficient than common silicon photovoltaic cells but is more efficient than some photovoltaic/thermal systems. Exhaustive parametric studies reveal that decreasing thermally regenerative electrochemical cycle internal resistance, ambient temperature or liquid flow rate in evacuated U-tube solar collector and increasing temperature coefficient or evacuated U-tube solar collector inlet temperature can enhance the hybrid system performance. Gradient-based local sensitivity analyses identify that the internal resistance and temperature coefficient of the electrochemical cycle are, respectively, the most and least sensitive variables. A practical case study predicts the hybrid system performance under local weather conditions.

Creeping thermocapillary motion of a Newtonian droplet suspended in a viscoelastic fluid

In this work we consider theoretically the problem of a Newtonian droplet moving in an otherwise quiescent infinite viscoelastic fluid under the influence of an externally applied temperature gradient. The outer fluid is modelled by the Oldroyd-B equation, and the problem is solved for small Weissenberg and Capillary numbers in terms of a double perturbation expansion. We assume microgravity conditions and neglect the convective transport of energy and momentum. We derive expressions for the droplet migration speed and its shape in terms of the properties of both fluids. In the absence of shape deformation, the droplet speed decreases monotonically for sufficiently viscous inner fluids, while for fluids with a smaller inner-to-outer viscosity ratio, the droplet speed first increases and then decreases as a function of the Weissenberg number. For small but finite values of the Capillary number, the droplet speed behaves monotonically as a function of the applied temperature gradient for a fixed ratio of the Capillary and Weissenberg numbers. We demonstrate that this behaviour is related to the polymeric stresses deforming the droplet in the direction of its migration, while the associated changes in its speed are Newtonian in nature, being related to a change in the droplet’s hydrodynamic resistance and its internal temperature distribution. When compared to the results of numerical simulations, our theory exhibits a good predictive power for sufficiently small values of the Capillary and Weissenberg numbers.

Temperature mapping model of cables considering the coupling of electromagnetic and thermal field

Background During cable operation, its internal temperature reflects the actual working condition of the cable. Once overload occurs, its conductor temperature will rise rapidly. Under high temperature conditions, the insulation material is very prone to breakdown accidents, which seriously threatens the safety of the power system. The traditional method of calculating the internal temperature of cables suffers from low accuracy and time-consuming problems. Methods To quickly and accurately calculate the cable’s internal temperature, a cable temperature mapping model is proposed with the coupling of electromagnetic and thermal field taken into consideration. Firstly, a finite element model is formulated based on the cable structure and material parameters. Secondly, the coupling between electromagnetic and thermal field is analyzed, and multiple coupling calculations are performed iteratively according to the operating conditions. Finally, the mapping between temperature and current is established using the exponential function. The cable surface temperatures under five operating conditions are measured online and compared with the calculated results of the temperature mapping model. Results Under five operating conditions, the average absolute error of the proposed model is 0.628 °C, and the average calculation time is 0.005 s. The average absolute error of the traditional model is 0.635 °C, and the average calculation time is 201.86 s. Conclusions The temperature mapping model developed in this paper can quickly and accurately calculate the cable’s internal temperature and forms an important part of the digital twin model of the cable.

Influence of atmospheric conditions and solar activity on the underground karst system of the Ponor Mountain

This study focuses on the meteorological parameters of the near atmosphere, the surface of the Earth and karst areas, such as temperature of water and air, relative humidity, and wind speed. These parameters are significantly influenced by solar activity, which in turn affects the temperature distribution in karst underground cavities, specifically in the &amp;ldquo;Kolkina Dupka&amp;rdquo; cave located within the Ponor Mountain of the Western Balkan Mountains range in Bulgaria. This is the deepest and longest cave in Bulgaria with a length of more than 20 km and a calculated depth of 800 m. Meteorological data within the cave was collected using data loggers, while surface weather data was sourced from National Institute of Meteorology and Hydrology of Bulgaria. Solar activity information was obtained from the website of the Royal Observatory of Belgium. The impact of solar activity on karst regions is substantial and affects temperature, precipitation, and atmospheric circulation. Changes in solar radiation can alter heat absorption on the surface of the Earth, leading to shifts in temperature and precipitation patterns. We performed statistical analysis and modeling to understand the complex interactions between Earth&amp;#39;s near atmosphere, the karst system of the Kolkina Dupka cave, and the role of air and water flows in regulating cave temperatures. Results showed a significant negative correlation between air temperatures in the deep underground airflows (at a depth of 130 m below the surface) and temperatures at the cave entrance (at a depth of 40 m during the winter months. Conversely, during spring and summer, an intriguing reversal occurs where higher external temperatures are linked to increased air temperatures at the cave entrance, accompanied by lower temperatures in the deeper zone. Furthermore, by employing &amp;ldquo;lagged correlations&amp;rdquo; in result analysis, investigating correlations between internal temperatures and external temperatures over the preceding and subsequent seven days, cyclic variations in heat exchange between the near-surface atmospheric layer and the underground temperatures within the karst system were observed. Specifically, a consistent temperature elevation was noted at the cave entrance three days prior to an increase in external temperatures during the spring-summer season. This temporal relationship was also observed in the solar activity data, where an increase in temperature at a depth of -40 m was registered three days prior to the escalation of solar activity within the measured range of 2800 MHz. The obtained results formed the basis for the development of new theories in solar-terrestrial physics. In summary, there is a connection between solar activity and Earth&amp;#39;s climate, but it is not a direct and simple correlation, and it is just one piece of the larger puzzle that shapes temperature variations of the Earth. Climate science involves studying these interactions over extended periods to gain a more comprehensive understanding of the climate system of the Earth.

A multi‐layer thermo‐mechanical coupling hysteretic model for high damping rubber bearings at low temperature

AbstractHigh damping rubber (HDR) bearings have been widely applied in seismic isolation of structures. However, the complex behavior of HDR bearings is influenced by thermal mechanism coupled with the seismic response of the structure, particularly at low ambient temperatures. In order to express the hysteretic restoring force behavior of HDR bearings involving temperature dependence, heating effect, and heat transfer with an improved accuracy, a multi‐layer thermo‐mechanical coupling model was developed. The thermal mechanism was illustrated by considering the heating effect and heat transfer in the multi‐layer thermal‐coupled model. A nonlinear hysteretic model including the temperature dependence of the stress‐strain relationship of rubber was incorporated. Quasi‐static cyclic loading was conducted for parameter identification and real‐time hybrid simulation tests were carried out for model validation. The model accurately represented the time‐dependent thermal mechanism within the bearing, considering the non‐uniform distribution of internal temperature. Numerical results exhibited good agreement with the experimental results, including the hysteresis curve, temperature history, and temperature distribution. The model demonstrated improved accuracy in computing the hysteretic behavior compared with an existing simple model.

Prediction of Condensation in the Heat Exchangers of Engine Intake Systems according to External Environmental and Operating Conditions

Low-pressure exhaust gas recirculation (LP-EGR) systems are applied to diesel engines because they reduce nitrogen oxide emission by lowering the internal temperature of the cylinder by mixing the oxides with intake air. However, low-temperature ambient conditions include a large amount of vapor in the mixed gas flowing into the intercooler; when heat is exchanged, the water vapor condenses and is adsorbed on the surface of the intercooler fin to form a liquid film. Condensation occurs as the thermal resistance between the vapor and solid surface increases with the thickness of the liquid film and causing a corrosion due to condensation of the surface. In this study, the amount of condensation was predicted through calculations based on thermodynamic studies. Factors that can cause condensation inside the intercooler (fuel, air, and LP-EGR) were selected as variables. A mathematical formula was established to predict the convergence form of condensation or the amount of condensation over time at various temperature and relative humidity conditions. The formula predicted the condensation amount in the intercooler of the diesel engine, compared it to the actual amount of condensation in the test evaluation with an error of less than 4%. Additionally, because the formula can predict the amount of condensation by changing the heat exchange area of the intercooler, the application range of the formula was expanded to predict the condensation in the intercoolers of gasoline vehicles with different heat exchange areas and fuel types. The condensation error was within 2%, indicating a high consistency. Validation of the formula predicts a reliable amount of condensation under various operating and ambient temperature conditions, which means that both the time and cost of the test evaluation require the determination of the cause before solving the actual condensation problem.

Determination of the softening point and temperature interval of asphalt mixture for the healing process based on the contactless nonlinear ultrasonic method

The softening point and gradient healing have significant engineering significance for the self-healing of asphalt mixtures. This study introduces a novel approach utilizing a contactless ultrasonic system in conjunction with the Second Harmonic Generation (SHG) technique to determine the softening point and monitor the gradient healing process of asphalt mixtures. Three distinct fracture patterns resulting from temperature variations are accurately characterized through simulation using the Discrete Element Method (DEM). The ultrasonic nonlinear parameter β, reflecting different crack interfaces, proves to be a highly effective alternative for characterizing asphalt fractures, outperforming traditional methods such as bearing force and wave velocity. In experimental analysis, variations in the healing index highlight the significant influence of asphalt mixture fracture patterns on healing efficiency. The observed decrease in ultrasound amplitude signifies the transition of the asphalt binder from a solid to a liquefied state, accompanied by an increase in the nonlinear parameter indicating enhanced plasticity. The softening point is precisely determined when the Rayleigh surface wave disappears. The cumulative healing process is visualized through the continuous decrease in the nonlinear parameter. To further enhance the understanding of the asphalt self-healing process, the internal temperature gradient field is characterized using the proposed energy difference method. A correlation between the nonlinear parameter and the depth of the temperature interval is established, providing a non-destructive method for evaluating the distribution of the temperature interval. This innovative approach significantly accelerates the development of non-destructive testing in the field of asphalt self-healing.

Numerical study on the thermal fluid of multi-chip test chamber with guide vane

This study describes a possibility for improved temperature uniformity by changing the chamber geometry using guide vane for application in test chambers. For the test chamber used in multi-chip testing, air cooling technology is commonly employed to maintain internal temperature and control the heat generated by semiconductor devices. The air cooling offers advantages such as simplicity of design and cost-effectiveness, however, it has the disadvantage of high dependence on fluid flow characteristics due to the shape of the internal space, making it prone to uneven airflow distribution at different locations. In order to perform especially package testing of semiconductor chips, it is necessary to actively control the target temperature in the test chamber to respond the rapidly changing temperature by heat generation of semiconductor chips. So, the accurate operation is request by the airflow control of test chamber in order to control the temperature of internal heat sources effectively. In this study, we conducted optimization research based on numerical analysis to improve temperature uniformity through efficient operation of airflow control of semiconductor package testing equipment. To analyze the accuracy of numerical analysis, we fabricated a test chamber identical to the analysis model and investigated the correlation between internal heat generation and fluid flow characteristics. It is anticipated that the validated methodology through numerical analysis and experimented research can provide a solution for achieving rapid response in attaining and maintaining the target temperature, which is essential for reducing semiconductor chip testing time to applied in an industrial context.

Thermally and mechanically induced strain gradient fields in architected 2D materials and beam structures

The current contribution investigates the strain-gradient thermomechanical performance of architected materials and structures with uniform and graded inner designs. To that scope, an integral representation of strain-gradients in thermoelasticity, along with its Galerkin Boundary Element Method (GBEM) implementation are elaborated. The formulation accounts for both mechanical and thermal strain-gradients for the first time. Thereupon, the complete strain-gradient response upon uniaxial tensile (UT) and thermal loading (Th) is analyzed, performing direct comparisons among the strain-gradient fields induced in each case and providing summarizing statistics that associate higher-order thermal and mechanical effects. The numerical framework is used as a basis for the quantification of the impact of the underlying structural patterns on the equivalent internal length parameters of architected beam-type structures under thermomechanical loads in the context of simple gradient theory. It is found that thermal loads relate to comparable, yet lower, internal length parameters with respect to the ones obtained for uniaxially tensioned structures with uniform inner cellular designs. Both internal length and temperature variation contributions determine the strain-gradient thermomechanical response of beam-type architected structures, for which, exact, higher-order equivalent 1D displacement field solutions are first derived. Thermally-induced, higher-gradient displacements are found to be comparable with the ones obtained in UT-loaded structures with uniform inner cellular topologies. Moreover, inner material gradings are found to be able to considerably mitigate higher-order effects, a sensitivity that is not reproduced in the UT loading case. The results provided, along with the numerical and analytical methodologies elaborated, set the basis for the thermomechanical strain-gradient analysis of advanced architected media well-beyond the designs here investigated.

To Shade or not to Shade (and how)? Annual heating energy balance and internal temperature in low energy houses in Wrocław, Poland.

One of the important areas of occupant–building fabric interaction with IEQ consequences is windows’ shading. The relevance of shading has been explored through modeling studies in the context of energy, daylighting and thermal comfort, typically aiming to inform the design stage. In owner occupied housing the architectural design sets the scene for subsequent residents’ decisions concerning windows treatment. Here, based on varied treatments for 20m2 living room window observed during an in-depth building performance evaluation in same homes, dynamic modeling in TRNSYS is used to establish the related heating loads and internal temperatures. The results allow to rank five shading usage scenarios for three physical settings, namely lack of shading, external blind and internal curtain on lower half of the window, in terms of their overheating mitigation potential, based on simplified assumptions for heating, ventilation and shading practices. The modelling points towards severe overheating issue and crucial impact of shading usage patterns on its mitigation. Yearly modelled share of overheating hours (>26 °C) are almost double for unshaded scenario compared to the most effective shading strategy (25% and 13%). The simulation contributes to understanding of the field monitoring results where the unshaded living rooms experience more severe overheating, and the two shading settings in place are associated with comparable internal thermal conditions, respectively 22% vs. 5% and 6% of yearly share of overheating hours. The simplification of human-HVAC-building interaction model likely obfuscates solar heat gain control contribution to heating load.