Non-uniform Temperature Distribution Research Articles

Structural Analysis of Thermal Diffusion and Non-Uniform Temperature Distribution along the Sidewall Thickness of STS316L during Gas Tungsten Arc Butt Welding

This study investigated how welding affects the thermal deformation of square cells produced for casks, which are dry storage containers for spent nuclear fuel. We aimed to minimize structural deformation by utilizing STS316L as the material for the square cells. We explored a method of subdividing the square cells and joining them through butt welding. Keeping the upper plate thickness constant, GTA butt welding was conducted while varying the column’s wall thickness, followed by measurement with a laser vision sensor. The heat conduction and thermal strain were then calculated using a finite element analysis (FEM). Both experimental and analytical results confirmed that there was significant thermal deformation in the cases of thick-walled columns due to variations in heat conduction distribution, with the resulting deformation patterns depending on thickness.

Thermoelectric power generation system intelligent Runge Kutta control: A performance analysis using processor in loop testing

As an emerging source of clean electrical power, Thermoelectric generation (TEG) finds its applications in heat removal and electricity generation as an efficient improvement tool for thermal devices utilizing fossil fuels. TEG exhibits low power density and its temperature distribution is usually non-uniform over thermal conductive surfaces. Due to the non-uniformity of heat flow and loose surface contact, non-uniform temperature distribution (NTD) appears on TEG surfaces and the TEG control problem becomes complex, multi-solution, nonlinear, and highly sensitive to operating conditions. The bypass diode activation of TEG systems streamlines the power flow in a string of series-connected modules, generating multiple peak points. Classical techniques fail to address these issues of multiple maxima and lose efficiency. To solve this problem, a novel SI-based optimization algorithm, Runge Kutta Method (RUN), is applied as MPPT control. To gauge the performance of the proposed controller several distinct case studies are used, including varying temperatures gradient, NTD, 24-hour thermal profile stochastic temperature, and experimental verification. Additionally, MPPT rating analysis, economic assessment, and statistical studies are done for comparison with other state-of-the-art control techniques. The minimum tracking and settling times have been improved by RUN to 180 ms. For the additional hardware implementation, the maximum levelized cost of energy (LCOE) is about 0.16 $kWh1.07¥kWh. The power tracking efficiency of RUN can be above 99 % with energy harvest improvements of 6.3 %.

The icing characteristic of stage 35 compressor blades and its impact on aerodynamic performance

The icing problem in aeroengine is prominent, posing a serious threat to flight safety. There are some limitations in current icing research for aeroengine, which limits the understanding of icing mechanism and potential impact. In this study, a 3D numerical method for air-water two phase flow in rotational situation is developed, and the icing thermodynamic model under the aeroengine environment is established. The study focuses on the icing characteristic of stage 35 compressor under different conditions, as well as the effect of icing shapes on aerodynamic performance. The results indicate that the icing distribution of stage 35 rotor shows obvious 3D characteristic, and the ice amount has an increasing trend with the rise of blade span. Due to the nonuniform distribution of temperature on rotor surface, the rime ice begins to transform into glaze ice from the top of blade when the temperature increases. The quantitative result also finds that the icing has a serious impact on compressor performance, in terms of mass flow, pressure ratio and isentropic efficiency. The flow obstruction caused by the blunt structure at the leading edge is the main reason affecting performance. The research indicates that the icing phenomenon in aeroengine is more complex than that on airfoil, and its threat to performance cannot be ignored in engineering.

Моделирование и анализ распределений температуры и термомеханических напряжений в многокристальном электронном модуле

A mathematical thermomechanical model of a multi-chip electronic module (MEM) containing three silicon dies of high-power transistors fixed with a conductive adhesive on a copper plate placed on a radiator is considered in the form of a system of equations of thermal conductivity and thermoelasticity with specified boundary conditions. As a result of computational studies of the model in the COMSOL Multiphysics software environment, distributions of temperature and thermomechanical stresses in the MEM structural elements were obtained depending on the heating power, the thickness of the adhesive and the size of the model defect in the contact connection of one of the MEM crystals with a copper plate in the form of voids in the adhesive layer. It is shown that voids in the adhesive layer lead to a sharply non-uniform temperature distribution over the crystal area and thermomechanical shear stresses in the contact layer that exceed the maximum permissible values for the adhesive. It has been established that thermomechanical stresses decrease with increasing thickness of the adhesive layer and increase with increasing size of the defect(voids) in this layer. The simulation results are in good agreement with the results of measuring the thermal impedance of power transistor crystals using the modulation method, which indicates the correctness and adequacy of the developed model.

Influence of tree planting pattern coupled with wall thermal effect on pollution dispersion within urban street canyon

Among the factors influencing the flow field and dispersion characteristics of pollutants in street canyons, trees not only act as obstacles that impede canyon ventilation but also contribute to non-uniform temperature distributions on its walls through transpiration and shading effects. The coupling effects, however, have not been given adequate attention. This study employed numerical simulations validated by wind-tunnel experiments to investigate the coupling effects of tree planting patterns (crown density Cd, planting density Pd) and wall heating conditions on airflow and pollutant diffusion within urban street canyons. Results show that the variations in Cd or Cd of the tree planting configurations studied have no significant impact on flow structure and pollutant dispersion in the isothermal street canyons. When Pd is 0.25, all three monitoring planes exhibit relatively high net escape velocity (NEV*) and notably reduced overall pollutant concentrations, indicating that this planting configuration is optimal for reducing pollution levels under leeward wall heating. When the windward wall is heated, the pollutant concentration is reduced more significantly under Pd of 0.25 and 0.75 while NEV* on the windward side is about 48. The average NEV* is minimized to approximately 21 at a Cd of 80 % when crown density or planting density is increased for all wall heating scenarios. Moreover, the other configurations of tree planting had little impact on ventilation and dispersion of pollutants in street canyons. The findings can offer technical guidance for the optimal design of urban green facilities to improve local microclimate environment and air quality.

Numerical thermal control design for applicability to a large-scale high-capacity lithium-ion energy storage system subjected to forced cooling

Overheating and non-uniform temperature distributions within the energy storage system (ESS) often reduce the electric capacity and cycle lifespan of lithium-ion batteries. In this numerical work, the thermal design inside the battery cabinet is explored. The battery cabinet has seven-level configurations with the suction fans located on the top of the ESS to efficiently realize heat dissipation. First, the numerical modeling is validated by the available experimental data, and the discrepancy in the maximum temperature increase between the experimental and computational results is found to be 3.2% or 0.64 K. Then, the optimum airflow rates of the fans are determined, where the single-cell model is also compared with the model of seven-level modules (i.e., 1/3ESS cabinet). Finally, the airflow channel widths, air gaps between the battery modules, as well as the air gaps between the 7th level module and the fans are examined. It is indicated for the precise model of 1/3ESS cabinet that: i) The maximum temperature rise of 4.63 K, and the maximum temperature variation of 2.14 K from cell to cell & the temperature uniformity of 2.82 K from module to module are all controlled with the requirements of operating temperature < 313.15 K, and temperature differences < 5.0 K, respectively; ii) The airflow channel width of 3.0 mm and the air gap of 10 mm between two adjacent modules & air gap of 20 mm between 7th level module and six parallel-fans are designed, and the ESS cabinet can increase the batteries of one level caused by the saved inside space.

Experimental and Numerical Study on the Protection Efficiency of a Diamond-Shaped Thermal Jacket for Gun Barrels

Abstract Experimental and numerical investigations on the protection efficiency of a diamond-shaped thermal jacket made of the certain braided composites with anisotropic material properties for gun barrels were carried out to gain an insight into its thermal–structural behavior and performance. The experiments for the gun barrels with and without the thermal jacket subjected to unilateral thermal radiation were conducted on a thermal jacket protection efficiency experimental system. Three-dimensional finite element models were established to perform the thermal–structural analysis and approximate the temperature distribution and thermal deformation of the shrouded gun barrel and bare gun tube. The experimental results validated the numerical models for the study of solar radiation on the thermal–structural characteristics of the gun barrels with and without the thermal jacket. The temperature changes together with their gradients, and the thermal deformation of the gun tube shrouded with the thermal jacket were notably less than that of the bare gun tube. The nonuniform temperature distribution caused by unilateral radiation can be substantially ameliorated by the thermal jacket. The developed diamond-shaped thermal jacket owned satisfactory protection effectiveness. In addition, moderately increasing the thermal jacket's thickness or the air gap between the thermal jacket and gun tube can decrease the muzzle deflection of the shrouded gun barrels. The work is promising in providing both theoretical and practical contributions in design of shrouded tank gun barrels aiming at achieving high first shot accuracy.

Natural draft direct dry cooling system performance at various application scales under windless and windy conditions

The natural draft direct dry cooling system (NDDDCS) presents a promising alternative to conventional forced draft air-cooled condensers (ACCs) and indirect natural draft dry cooling systems, overcoming their limitations by efficiently condensing process steam directly and passively. The NDDDCS achieves superior thermal efficiencies while reducing system complexities, operational costs, and auxiliary power consumption. Potential reductions in operational expenses for the system may offset initial capital investments, resulting in lower lifetime costs. While research to date has focused on large-scale NDDDCS performance under varying wind conditions, this work addresses a critical gap by investigating the system’s scalability for various applications, including a large-scale coal-fired power plant (900 MWt, 165 m total height), a medium-scale concentrated solar power plant (CSP) (100 MWt, 65 m total height), and a small-scale water desalination plant (1 MWt, 11.5 m total height) under both windless and windy conditions. To achieve this, a steady-state 3-D computational fluid dynamics (CFD) model is developed, validated and scaled, incorporating innovative features such as an atmospheric pressure gradient and the ability to capture reversed flows through the system’s heat exchangers. Additionally, the model assesses inlet air temperature data at a per-cell resolution, enabling the ability to predict non-uniform temperature distributions in the heat exchangers, including hot-spots caused by airflow recirculation. Analysis of velocity and temperature fields across all scales reveals that recirculation effects negatively impact NDDDCS performance, particularly at the middle circumferential heat exchanger sector. The hyperbolic shape of the tower shell induces internal recirculation zones and reduces the effective flow volume. Under windy conditions, performance losses of 44%, 40%, and 40% are observed at crosswind speeds of 3 m/s, 6 m/s, and 9 m/s for small, medium, and large-scale towers, respectively. Beyond these speeds, the relationship between system performance and draft driving potential becomes non-linear due to crosswind effects dominating. Furthermore, a novel effect is identified at wind speeds of 9 m/s, 15 m/s, and 18 m/s for small, medium, and large-scale systems, respectively, where an inflection point allows for system performance recovery. This study underscores the NDDDCS’s potential as a cooling solution for modern power cycles across various scales, while highlighting the implications of scaling the system for medium- and small-scale thermal applications.

Экспериментальное и численное исследование нагрева стенок камеры сгорания малоразмерного газотурбинного двигателя

The combustion chamber is one of the main components that determine the energy and mass characteristics of the propulsion system. A detailed description of the combustion chambers of some model engines running on kerosene is given. The results of fire tests and numerical studies of combustion chambers of model small-sized gas turbine engines are considered. To qualitatively compare the results of calculations with the data of a physical experiment, annealed colors are used. Based on the results of the research, a map of tem perature distribution on the walls of the combustion chamber was compiled. The internal and external surfaces of the combustion chamber are unevenly colored with tarnished colors. This coloring is a consequence of non-uniform distributions of temperature and concentration of various components of combustion products, and also indicates the formation of a spatial flow in the combustion chamber.

The role of near-wall downdraught and asymmetric temperature distribution in dispersion of respiratory aerosols in radiant floor heating systems

In radiant floor heating (RFH) systems, the downdraught due to the asymmetric temperature distribution causes descending airflows towards the floor surface, where the warm air adjacent to the RFH system tends to be driven upwards by the buoyancy force. Hence, this conflict creates a zone that prevents the warm air to ascend affecting the streamlines of the indoor air. The present study aims to investigate the integrated effects of this phenomenon at different levels of the RFH temperature and thermal transmittance on the behaviour of indoor airborne particles (PMs2.5). In this context, a Eulerian-Lagrangian computational fluid dynamic (CFD) code is established, validated against experimental data, to address the dispersion and deposition patterns of PMs2.5. To generate different levels of the downdraught and non-uniform temperature distribution, five scenarios are considered regarding different thermal transmittance (U-value) levels, assessed for four RFH temperatures. Firstly, by introducing the near-wall and zonal spaces, the dispersion of particles in each scenario is evaluated. Then, the role of RFH system temperature in conjunction with each scenario is investigated. Finally, simple correlations are proposed allowing for fast evaluation of the decay rate coefficient of PMs2.5. According to the obtained results, the asymmetric temperature distribution causes a striking disparity in the zonal concentration of suspended PMs2.5, i.e., up to 32 % difference in the number of particles between quarters. It is shown that a faster decay rate of PMs2.5 is associated with a larger value of the characteristic temperature difference and the Rayleigh number (Ra). For a given RFH temperature, thermal performance improvement of the envelope reduces the number of deposited particles on the ceiling surface, whereas it gives a boost to the number of particles adhering to the floor. A sensitivity analysis on the results revealed that a 1 °C increment in the RFH temperature leads to an 8.4 % reduction on average in the number of suspended PMs2.5 in the breathing zone, regardless of the level of thermal transmittance from surrounding walls.

LBM Simulation of Free Convection Heat Transfer of Cu/Water Nanofluid in Inclined Cavity with Non-Uniform Heating Temperature Distribution

In the present study, natural convection of Cu/water nanofluid in an inclined square cavity has been investigated numerically using lattice Boltzmann method (LBM). The left wall of the cavity is maintained at a constant hot temperature, while the right wall is subjected to non-uniform temperature distribution. The upper and lower walls are insulated. The fluid flow and heat transfer characteristics are investigated over a wide range of parameters, including Rayleigh numbers (Ra = 103, 104 and 105), solid volume fractions (Φ = 0%, 2%, 4% and 6%), amplitude ratio (A = 0, 0.5 and 1) and phase deviations of sinusoidal temperature distribution (Φ = 0, π/4, π/2, 3π/4 and π). The results are presented graphically in the form of streamlines, isotherms and Nusselt numbers for the different combinations of the considered parameters. The heat transfer rate inside the nanofluid increases as the Rayleigh number and the volume fraction of nanoparticles increase. Further, an increase in the amplitude ratio results in a decrease in the heat transfer rate, with a reduction of up to 8.67% at A = 1. On the other hand, changes in the phase deviation of the sinusoidal temperature distribution lead to an increase in the heat transfer rate, with a surge of up to 32.04% observed at Φ = π.

Numerical simulation for non-uniform PtCo catalyst degradation under different coolant conditions and its effect on PEMFC performance

Long-term non-uniform temperature, pressure and reaction rates distributions in the proton exchange membrane fuel cells (PEMFCs) may result in local catalyst degradation and deteriorate PEMFC performance. However, the problem of non-uniform catalyst degradation in PEMFC stacks is still incompletely understood due to the lacking of advanced experimental methods and three-dimensional (3D) catalyst aging models. In this study, a 3D PtCo alloy catalyst degradation model under voltage cycles is built and a 25 cm2 PEMFC stack containing realistic cathode, anode as well as coolant flow fields is used as the computational domain to analyze in detail the influence of non-uniform catalyst degradation on the performance of the PEMFC during different coolant conditions. The simulation results show that the non-uniform catalyst degradation is strongly dependent on the cathode flow field structure. It can alleviate non-uniform catalyst degradation as well as contribute to improving PEMFC performance when the coolant flow direction is the same as the air, and both coolant flow rate and inlet temperature also are found to significantly affect the local catalyst degradation behavior. Therefore, an optimally designed cathode flow fields structure as well as good water and heat management during operation can help to extend the service life of the PEMFC.

Thermal boundary conditions for heat transfer analysis of bridges considering non-uniform distribution of internal air temperature by computational fluid dynamics

AbstractHeat transfer analysis has been used to calculate the temperature distribution in bridges. Thermal boundary conditions play a critical role in this analysis. However, existing studies on thermal boundary conditions simplify the air temperature inside the bridge deck as uniform, which is not realistic and thus causes inaccurate simulation results. This study proposes a new approach to thermal boundary conditions in the heat transfer analysis of bridges. For the first time, computational fluid dynamics is used to calculate non-uniform air temperatures inside the bridge deck. In addition, non-approximate heat exchange equations for long-wave radiation are also incorporated into the approach. The techniques are applied to the 1377-m main span Tsing Ma Suspension Bridge to calculate the internal air temperatures of a deck segment. Transient heat transfer analysis is then conducted to calculate the time-dependent temperature distribution of the segment. As compared with the field monitoring results, the proposed approach can simulate the temperature distribution of the bridge with an average discrepancy of 0.88 °C and is more accurately than other existing approaches.

Calculation method of electromagnetic losses and hot-spots temperature of giant magnetostrictive transducer

Due to the complex energy conversion processes and limited avenues for heat dissipation in the giant magnetostrictive transducer (GMT). Large losses and elevated internal temperature rise are inevitable, this would bring into serious reliability problem for GMT. Accurately analyzing its electromagnetic losses and hot-spots temperature are crucial for designing and optimizing the transducer. High-power GMT typically use permanent magnet (PM) to provide a bias magnetic field for enhanced power density. Although, this structure could significantly reduce the volume of driving part, it also caused issues such as non-uniform magnetic field distribution and bias magnetic field, which have great influence on the magnetic energy loss and hot-spots temperature rise. The previous researches seldomly investigate these influences on total loss at GMT system level. Additionally, the differential excitation coil loss caused by AC resistance among multi-layers can’t be neglected, which can lead to variations in coil loss and temperature rise. Therefore, this paper proposed a detailed electromagnetic losses and hot-spots temperature rise calculation model from material level to GMT system level. This method can obtain the distribution of electromagnetic losses within multiple factors, and the hot-spots temperature rise considering the temperature non-uniform distribution. Firstly, we have developed a precise loss calculation model, which takes the influence caused by PM bias and non-uniform magnetic field on magnetic energy loss into account. Additionally, the proposed model could conclude the impact of inter-coil resistance variations on the eddy current loss in excitation coil. Secondly, based on of the non-uniform distribution of losses in driving part, using the divisional thermal modeling approach and a 2-D T-shaped equivalent thermal network, we further constructed a transient temperature calculation model for GMT. This approach can effectively improve the energy conversion efficiency of GMT, so as to enhance the thermal reliability of the transducer. Finally, a testing system for the loss-thermal of GMT was established to validate the effectiveness of proposed model. Results indicate that the average error between our loss calculation model and experimental results is 2.93%, while the corresponding error for without considering the above factors is 15.97%. This confirms the necessity of conducting a detailed electromagnetic losses calculation model. In addition, the average error of the temperature rise calculation model is less than 5%, while the error for without considering the losses distribution and heat dissipation paths difference is exceed 10%. In conclusion, our proposed method accords well with the measured results, and can provide significant fundamental for design and optimization of GMT.

Numerical investigations and design optimization of cryogenic plate-fin heat exchanger in Electric Arc Furnace using radiative heat transfer model

The most crucial element affecting cryogenic systems’ energy efficiency is heat exchangers. In this article, a model for cryogenic plate-fin heat exchanger (PFHE) under thermal-hydraulic performance with various blends is proposed. To reduce five objective functions total heat transfer rate, total weight, total mass flow rate, number of entropy generating units, and whole annual cost the study carried out the PFHE’s optimal design. This study innovatively focuses on optimizing PFHE design for cryogenic conditions using Opposition Learning with the Beetle Swarm algorithm. The proposed geometry addresses non-uniform temperature distribution, emphasizing thermal-hydraulic properties in various blends. Additionally, a second-order semi-discretization radiative heat transfer approach enhances boiler simulation accuracy. A multi-objective optimization of Opposition Learning with Beetle Swarm (MO-OBBS) optimization approach was suggested in the article for the design of PFHE. Despite the significant potential for renewable energy the low-temperature waste heat treatment process is rarely examined from a sustainability perspective. Consequently, the study proposed a second-order semi-discretization radiative heat transfer method to simulate a furnace using a water heat recovery process. The cooling panel’s numerical analysis was conducted using computed temperature fields. The performance of the various algorithms is compared using the Freidman rank-sum test to determine the statistical significance of the findings obtained. In logarithmic coordinates, the proposed method’s faster convergence is compared to GQB-PSO, SLTLBO, Jaya, CKKO, and OLE-SCA algorithms. The proposed method exhibits a maximum average increase of 115.39% for PFHE design. When the numerical simulation results are compared to measurements of output water temperature, the accuracy is highly improved.

An experimental method of determination and validation of latent thermal energy storage dynamic characteristic by effective enthalpy

The paper draws attention to the problems of evaluating stored heat capacity in a latent heat thermal energy storage (LHTES) that operates with unsteady inlet temperature conditions. These problems are studied for custom-built LHTES designed to be charged/discharged at varying heat transfer rates in a chilled water system. The LHTES incorporates a typical fin and tube heat exchanger and commercially available ATP 20 phase change material (PCM). For the designed storage construction, the ratio of heat transfer area to PCM volume is 354 m2/m3, and the ratio of PCM volume to the total volume (compactness factor) is 0.87. The LHTES thermal characteristics were investigated on a test stand using inlet temperature inputs changing linearly at 1, 2 or 3 K/h. During each test, a complete phase transition in the PCM was ensured. Based on LHTES inlet and outlet temperature profiles, enthalpy distributions versus outlet temperature were evaluated. The experiments proved that these distributions are not a material property as they depend on the geometric characteristics of the LHTES and charging/discharging rates. However, they can describe the thermal behaviour of the PCM filling the LHTES and include the influence of a non-uniform temperature distribution inside the LHTES on the PCM hysteresis and temperature range of the complete melting/solidification. These effects can be modelled by the proposed function of effective enthalpy. The effective enthalpy allows for relatively simple monitoring of phase transition progression in the LHTES based solely on the parameters measurable outside the storage.

Analytical and experimental analyses on cooling performances of radiative SkyCool radiators with various interior flowing channels

This study presents an analytical model for the radiative SkyCool radiators (RSCR) with various interior flowing channels by using Laplace transformations. Moreover, the convolution theory is applied to solve the problem of nonuniform temperature distribution on the RSCR. Then, an outdoor experiment is carried out to verify the proposed model. Subsequently, the influence of different channel geometries, flow rates, tilt angles and wind velocities on the cooling performances of RSCRs are investigated. The results indicate that increasing the RSCR's length, enlarging the pipe spacing, and decreasing the flow rate and thickness of RSCR can definitely intensify the cooling performances. The application suggestions for S-channel RSCR (SRSCR) and I-channel RSCR (IRSCR) are given. When the pipe spacing ratio is smaller than five, the IRSCR is recommended because of lower thermal interferences. By contrast, SRSCR is recommended once the dimensionless pipe spacing is greater than ten. For cases with smaller tilt angles but larger wind velocities, IRSCR is suggested, while SRSCR is prioritized for cases with opposite conditions. This research provides an effective analytical tool in the evaluation of cooling power generation by producing cold water, contributing valuable insights for the optimization of cooling efficiencies of RSCRs under varied configuration scenarios.

Numerical Simulation and Experimental Verification of the Quenching Process for Ti Microalloying H13 Steel Used to Shield Machine Cutter Rings

Owing to the non-uniform distribution of chemical composition and temperature during the heat treatment process, the residual stress and deformation of the workpiece emerge as crucial factors requiring consideration in managing the service performance and lifespan of shield machine cutter rings crafted from H13 steel. Considering H13 steel with titanium microalloying as the research object for the shield machine cutter ring, we simulate the quenching process using Deform-3D. The temperature field, phase transformation, stress evolution, and deformation amount after quenching are analyzed. The results demonstrate a strong agreement between the simulation and experimental results, offering valuable insights for optimizing the heat treatment process and enhancing the overall performance of shield machine cutter rings.

Multiwavelength Pulsations and Surface Temperature Distribution in the Middle-aged Pulsar B1055–52

We present a detailed study of the X-ray emission from PSR B1055–52 using XMM-Newton observations from 2019 and 2000. The phase-integrated X-ray emission from this pulsar is poorly described by existing models of neutron star atmospheres. Instead, we confirm that, similar to other middle-aged pulsars, the best-fitting spectral model consists of two blackbody components, with substantially different temperatures and emitting areas, and a nonthermal component characterized by a power law. Our phase-resolved X-ray spectral analysis using this three-component model reveals variations in the thermal emission parameters with the pulsar’s rotational phase. These variations suggest a nonuniform temperature distribution across the neutron star’s surface, including the cold thermal component and probable hot spot(s). Such a temperature distribution can be caused by external and internal heating processes, likely a combination thereof. We observe very high pulse fractions, 60%–80% in the 0.7–1.5 keV range, dominated by the hot blackbody component. This could be related to temperature nonuniformity and potential beaming effects in an atmosphere. We find indication of a second hot spot that appears at lower energies (0.15–0.3 keV) than the first hot spot (0.5–1.5 keV) in the X-ray light curves and is offset by about half a rotation period. This finding aligns with the nearly orthogonal rotator geometry suggested by radio observations of this interpulse pulsar. If the hot spots are associated with polar caps, a possible explanation for their temperature asymmetry could be an offset magnetic dipole and/or an additional toroidal magnetic field component in the neutron star crust.

Indoor comfort management and energy consumption in Arctic buildings: Occupant perceptions in an indigenous community of Canada

Arctic and subarctic communities currently face major and unique energy and housing challenges. However, the perceptions, needs, and adaptive strategies of occupants related to energy consumption and comfort in their dwellings are not well known. In this study, 16 semi-structured interviews were conducted in the Inuit community of Quaqtaq (Nunavik, Quebec, Canada) to investigate occupants’ experiences, observations, and perceptions on these topics. The topics covered comfort, window opening, use of curtains, and usage of thermostats, water, and lighting. Furthermore, awareness of energy consumption and renewable technologies was investigated, and occupants shared their vision of the ideal home. It was found that windows and thermostats are often used simultaneously to regulate temperature and that non-uniform temperature distribution and cold floors were often noted by occupants. Due to the limited amount of water available, coordination with neighbors was needed for activities requiring water. Awareness and interest in energy savings and renewable energy varied significantly among participants. Participants mentioned that their ideal home would have better insulation, larger water tanks, and more storage space. These results help to understand occupant behavior, energy consumption patterns, and well-being in houses of northern communities and can guide the development of future housing units.