Spatial Temperature Profiles Research Articles

Catalyst pellets with Gaussian activity distribution under forced periodic operation for reactions with Langmuir-Hinshelwood kinetics

This research investigates how combining forced periodic operation with spatially distributed catalyst activity can enhance heterogeneous catalytic processes. It focuses on analyzing reaction-diffusion phenomena within porous catalyst pellets. These pellets exhibit a Gaussian distribution of active sites, and the study investigates how externally forced periodic variations in bulk reactant concentration and temperature affect the reaction process. The paper establishes a mathematical model for a non-isothermal reaction based on Langmuir-Hinshelwood kinetics. This model is then transformed into its dimensionless form for numerical analysis. Numerical simulations are employed to investigate the impact of various parameters on the concentration and temperature profiles within the pellet, as well as on the pellet productivity. These parameters include the position and width of the Gaussian distribution of active sites, the Thiele modulus, the mass and heat Biot numbers, the Arrhenius number for reaction, the energy generation function, the ratio of characteristic times for diffusion and heat conductivity, and frequencies and amplitudes of periodic variations. The simulations reveal complex relationships between the spatial and temporal profiles of concentration and temperature within the pellets. Using porous granules with a non-uniform catalyst activity profile alongside forced periodic operations for reaction-diffusion processes enables higher productivity compared to granules with a uniform activity profile and subject to the steady-state operation. This study demonstrates the potential for optimizing catalytic processes in porous pellets with non-uniform activity profiles under forced periodic operation, offering valuable insights into enhancing process efficiency.

Detecting neoclassical tearing modes in high-temperature ITER plasma scenarios with the ITER prototype electron cyclotron emission diagnostic

Abstract Electron cyclotron emission (ECE) diagnostics for ITER serve two key purposes. The diagnostics will measure plasma electron temperature with high spatial and temporal resolution. Additionally, they will be used to detect neoclassical tearing modes (NTMs), a deleterious and nonlinearly unstable mode causing the growth of magnetic ‘seed’ islands. Interpreting ECE requires anticipation of physical limits including frequency cut-offs and harmonic overlap. In high temperature plasmas, the relativistic shift and broadening of the emission must also be considered to accurately reconstruct the electron temperature spatial profile. Accounting for these effects allows ECE diagnostics to be used for accurate measurement of the equilibrium electron temperature profile, as well as fluctuations about this equilibrium. One such fluctuation is caused by the fast radial transport of heat across rotating magnetic islands. ECE diagnostics can detect this change as an oscillation at the plasma rotation frequency to determine the existence and location of NTMs. This paper presents work on a synthetic diagnostic for ECE. The synthetic diagnostic tests simulated ECE signals, which are inferred from ITER scenarios perturbed by magnetic islands after accounting for all ECE physics. The synthetic diagnostic tests conventional ECE detection algorithms for NTMs in real-time on ITER-recommended hardware. Combined, these two areas of focus help determine design of the ECE system.

Quantifying the thermal effect and methyl radical production in nanosecond repetitively pulsed glow discharges applied to a methane-air flame

In this work, we investigated non-equilibrium plasma produced by nanosecond repetitively pulsed glow discharges applied across a lean premixed methane-air flame. The flame is stationary, axisymmetric, and laminar. The discharges are applied on the symmetry axis crossing the reactant gases, flame front, and product gases, allowing phase-locked averaged measurements and comparisons with axisymmetric numerical simulations. The thermal effect and methyl radical production are quantified in the discharge in the reactant gas region. One-dimensional, two-beam, hybrid, femtosecond-picosecond, coherent anti-Stokes Raman scattering is used to acquire spatial and temporal profiles of temperature and oxygen-to-nitrogen concentration ratio. Photo-fragmentation laser-induced fluorescence is used to acquire quantitative two-dimensional profiles of methyl radicals in the discharge providing the first quantitative imaging of methyl produced ahead of a flame by plasma-induced methane dissociation. The spatial profiles of temperature and oxygen-to-nitrogen concentration ratio are in steady state, indicating that individual discharges have an insignificant heating effect. Upper and lower bounds of the produced mole fraction of methyl radicals in the plasma are obtained due to uncertainties in the collisional quenching rates of excited state methylidyne radicals in the plasma. The discharges produce a maximum of 600–1100 ppm of methyl radicals upstream of the flame front within 25 ns. This amount is similar to the predicted methyl mole fraction for the flame without plasma and thus represents a significant chemical perturbation to the reactants upstream of the flame front. The produced methyl follows an exponential decay in the first microsecond after the discharge with a decay constant of 8 µs close to the flame, and 0.8 µs further from the flame. The decay then deviates from the exponential curve and the methyl persists for tens of microseconds. The results suggest that for the tested configuration, the thermal effect of individual discharges through fast gas heating is negligible, while active chemical species are produced in large quantities in the reactant gases, upstream of the flame front.

Predicting and Probing the Local Temperature Rise Around Plasmonic Core-Shell Nanoparticles to Study Thermally Activated Processes.

Ultrafast spectroscopy can be used to study dynamic processes on femtosecond to nanosecond timescales, but is typically used for photoinduced processes. Several materials can induce ultrafast temperature rises upon absorption of femtosecond laser pulses, in principle allowing to study thermally activated processes, such as (catalytic) reactions, phase transitions, and conformational changes. Gold-silica core-shell nanoparticles are particularly interesting for this, as they can be used in a wide range of media and are chemically inert. Here we computationally model the temporal and spatial temperature profiles of gold nanoparticles with and without silica shell in liquid and gas media. Fast rises in temperature within tens of picoseconds are always observed. This is fast enough to study many of the aforementioned processes. We also validate our results experimentally using a poly(urethane-urea) exhibiting a temperature-dependent hydrogen bonding network, which shows local temperatures above 90 °C are reached on this timescale. Moreover, this experiment shows the hydrogen bond breaking in such polymers occurs within tens of picoseconds.

Exploring BTI aging effects on spatial power density and temperature profiles of VLSI chips

The Long-term reliability of a chip, encompassing factors like bias temperature instability (BTI), plays a substantial role in the chip's operational efficiency and overall lifespan. Most studies primarily center around performance-related aspects like delay and timing impacts, and fewer studies are performed on reliability impacts on the spatial power density and thermal profiles of the chips. In this study, we propose to investigate the BTI impacts on the spatial power density and temperature profiles of VLSI chips for the first time. We assessed the BTI aging impact on the on-chip spatial power density and temperature for two widely used circuit functional blocks (dual port RAM, Discrete Cosine Transform (DCT) block) at T = 130◦C and T = 25◦C to account for the worst-case BTI degradation, using degradation-aware cell libraries for a 10-year aging scenario. Furthermore, we showcased the essential role of BTI aging-aware timing analysis in evaluating the impact of BTI aging on total power, on-chip spatial power density, and thermal maps. Neglecting this aspect can result in a substantial underestimation of the results related to the parameters mentioned above. We developed a power map generation method from the circuit layout and power analysis from EDA tools. We demonstrate that both circuits’ maximum power density reduction is approximately 12 % and 20 %, respectively. Furthermore, to analyze the BTI impact on spatial temperature, we built the heat transfer model using a multiphysics tool to imitate a real chip (Intel i7-8650U) and performed thermal simulations to evaluate the spatial thermal map. The resulting maximum temperature reduction for both these circuits is approximately 10 % and 12 %, respectively, which is quite significant.Our analysis has further unveiled that, in the context of a specific circuit, the position of maximum power density and the occurrence of a hot spot remains consistent over time, unaffected by aging. However, it's important to note that these positions can vary between different circuits, primarily influenced by the workload the circuit is currently handling. Furthermore, our findings demonstrate that the effects of Bias Temperature Instability (BTI) aging are significantly more pronounced when the circuit operates at higher temperatures (T = 130◦C) compared to lower operating temperatures (T = 25◦C).

Effect of antenna helicity on discharge characteristics of helicon plasma under a divergent magnetic field

The characteristics of the blue core phenomenon observed in a divergent magnetic field helicon plasma are investigated using two different helical antennas, namely right-handed and left-handed helical antennas. The mode transition, discharge image, spatial profiles of plasma density and electron temperature are diagnosed using a Langmuir probe, a Nikon D90 camera, an intensified charge-coupled device camera and an optical emission spectrometer, respectively. The results demonstrated that the blue core phenomenon appeared in the upstream region of the discharge tube at a fixed magnetic field under both helical antennas. However, it is more likely to appear in a right-handed helical antenna, in which the plasma density and ionization rate of the helicon plasma are higher. The spatial profiles of the plasma density and electron temperature are also different in both axial and radial directions for these two kinds of helical antenna. The wavelength calculated based on the dispersion relation of the bounded whistler wave is consistent with the order of magnitude of plasma length. It is proved that the helicon plasma is part of the wave mode discharge mechanism.

Vulnerability Assessment of a Highly Populated Megacity to Ambient Thermal Stress

The urban ambient environment is directly responsible for the health conditions of millions of people. Comfortable living space is a significant aspect that urban policymakers need to address for sustainable planning. There is still a notable lack of studies that link the spatial profile of urban climate with city-specific built-up settings while assessing the vulnerability of the city population. Geospatial approaches can be beneficial in evaluating patterns of thermal discomfort and strategizing its mitigation. This study attempts to provide a thorough remote sensing framework to analyze the summer magnitude of thermal discomfort for a city in a tropical hot and humid climate. Spatial profiles of dry bulb temperature, wet bulb temperature and relative humidity were prepared for this purpose. A simultaneous assessment of various discomfort indices indicated the presence of moderate to strong heat stress to a vast extent within the study area. The central business district (CBD) of the city indicated a ‘danger’ level of heat disorder for outdoor exposure cases. Nearly 0.69 million people were vulnerable to a moderate threat from humid heat stress, and around 0.21 million citizens faced strong heat stress. Combing city morphology in the study showed that mid-rise buildings had the maximum contribution in terms of thermal discomfort. City areas with built-up cover of more than 68%, along with building height between 5.8 m and 9.3 m, created the worst outdoor discomfort situations. Better land management prospects were also investigated through a multicriteria approach using morphological settlement zones, wind direction, pavement watering, building regulations and future landscaping plans. East–west-aligned road segments of a total 38.44 km length were delineated for water spray cooling and greener pavements. This study is likely to provide solutions for enhancing ambient urban health.

Spatio-temporal analysis of power deposition and vibrational excitation in pulsed N2 microwave discharges from 1D fluid modelling and experiments

Vibrational excitation of N2 beyond thermodynamic equilibrium enhances the reactivity of this molecule and the production of radicals. Experimentally measured temporal and spatial profiles of gas and vibrational temperature show that strong vibrational non-equilibrium is found in a pulsed microwave discharges at moderate pressure (25 mbar) in pure N2 outside the plasma core and as an effect of power pulsing. A one dimensional radial time-resolved self-consistent fluid model has been developed to study the mechanism of formation of vibrationally excited N2. In addition to the temperature maps, time-resolved measurements of spontaneous optical emission, electron density and electron temperature are used to validate the model and the choice of input power density. The model reveals two regions in the plasma: a core where chemistry is dominated by power deposition and where vibrational excitation starts within the first ∼10 µs and an outer region reliant on radial transport, where vibrational excitation is activated slowly during the whole length of the pulse (200 µs). The two regions are separated by a sharp gradient in the estimated deposited power density, which is revealed to be wider than the emission intensity profile used to estimate the plasma size. The low concentration of excited species outside the core prevents the gas from heating and the reduced quenching rates prevent the destruction of vibrationally excited N2, thereby maintaining the observed high non-equilibrium.

3-D scanned oven geometry improves the modeling accuracy of the solid-state microwave heating process

Solid-state-based microwave ovens are promising to mitigate the non-uniformity issue for their precise controlled microwave parameters. Multiphysics modeling is a useful tool for understanding complicated microwave heating processes. However, previous models using simple or manually measured oven geometry had challenges in accurately predicting the heating patterns. This study developed a 3-D scanning approach to characterize the accurate geometric details of the cavity and incorporate it in the multiphysics modeling of solid-state microwave heating. The effect of oven geometric details on modeling accuracy was evaluated for models using the simple box, manually measured, and 3-D scanned geometries at multiple microwave frequencies and port locations. A quantitative approach was also developed to replace the previously often-used qualitative approach to compare the spatial temperature profiles between the simulation and experiments. The Multiphysics-based models using 3-D scanned geometry showed significantly or considerably smaller RMSE values (1.57 to 4.11 °C) than the models with simple box geometry (1.73 to 6.33 °C) and manually measured geometry (1.48 to 4.66 °C) at most heating scenarios. The 3-D scanned approach can accurately incorporate the irregular geometric details of the oven cavity and can improve the prediction accuracy of microwave heating models for future food products and oven development.

Light‐Driven Thermo‐Optical Effects in Nanoresonator Arrays

AbstractThermonanophotonics, that is the study of photothermal effects in optical nanoantennas, has recently attracted growing interest. In particular, going beyond thermoplasmonic designs, thermo‐optical modulation of dielectric nanoantennas opens new opportunities for reconfigurable and non‐reciprocal metasurfaces. However, understanding light‐driven thermo‐optical effects in large arrays of nanoantennas remains challenging. In this work, for the first time the impact of thermo‐optical effects beyond the single nanoresonator is analyzed. By performing photo‐thermo‐optical computations of large nanoantenna arrays (more than 105 elements), the complex interplay of thermo‐optical effects with self‐ and collective‐heating in 1D, 2D, and 3D systems are explored. The results show that collective heating contributions strongly alter the local absorption cross‐section and, in return, also the self‐heating term. Therefore, both terms must be carefully accounted for in large arrays. Importantly, by controlling the nanoresonator size, array periodicity and illumination wavelength, thermo‐optical effects enable the realization of non‐trivial spatial temperature profiles. In particular, ways to counteract collective heating effects and obtain flat temperature profiles in 2D arrays of dissimilar silicon nanoresonators are demonstrated. Overall, this work paves the way to the design of light‐driven reconfigurable metasurfaces, supporting the development of advanced thermonanophotonic functionalities.

Spectroscopic measurement of increases in hydrogen molecular rotational temperature with plasma-facing surface temperature and due to collisional-radiative processes in tokamaks

Spatially resolved rotational temperature of ground state hydrogen molecules desorbed from plasma-facing surface was measured in QUEST, LTX-β, and DIII-D tokamaks, and the increases of the rotational temperature with the surface temperature and due to collisional-radiative processes in the plasmas were evaluated. The increase due to collisional-radiative processes was calculated by solving rate equations considering electron and proton collisional excitation and deexcitation and spontaneous emission. The calculation results suggest a high sensitivity for the rotational temperature to electron and proton densities, but a negligible sensitivity to the electron, proton, and surface temperatures. In the three tokamaks with different plasma parameters and plasma-facing surface materials, the spatial profile of the rotational temperature was estimated using Fulcher-α emission lines (600–608 nm). In QUEST, the spatial profile of the rotational temperature was estimated from spatially resolved spectra. In the other tokamaks, the rotational temperature was evaluated assuming a single point emission with a location determined from the Fulcher-α emission profile as measured with a filtered camera. In metal-walled devices QUEST and LTX-β, the rotational temperature increased with the surface temperature, and the calculated collisional-radiative increase is consistent with measured increase assuming that the rotational temperature at the surface is approximately 500–600 K higher than the surface temperature. In DIII-D with carbon walls, a larger collisional-radiative increase than the other tokamaks was observed because of the higher density leading to a large difference from the calculated increase compared to the other smaller tokamaks. Measurement of the Fulcher-α emission profile with higher spatial resolution in DIII-D may reduce the difference and reveal the effect of the surface temperature on the rotational temperature. These results show the increases in the rotational temperature with the surface temperature and due to the collisional-radiative processes.

Statistical analysis of similarity of plasma parameters profiles at quasi-stationary stage of discharge in JET tokamak

A statistical analysis is carried out of the similarity of profiles of plasma parameters: electron temperature T e, density n e, and pressure P e, at the stage of quasi-stationary plasma current (the so called flat-top stage) of about 9000 discharges in the JET tokamak, among the discharges from #84458 to #99419 that covers almost the entire database of successful discharges in the JET ITER-like wall machine. For all these parameters, the existence of universal profiles is shown as functions of the normalized minor radius of the plasma column ρ. The discharge universal profiles (DUPs) are obtained by dividing the space-time-dependent profile by its value at the center of the plasma column or by the space-averaged value of this parameter in the region ρ ⩽ ρ max = 0.5–1, and subsequent averaging over time at the flat-top stage of each discharge. The machine universal profiles (MUPs) are obtained by averaging over time of flat-top stage of all discharges. It is shown that for 86% of the discharges, the time-averaged relative root-mean-square deviation of P e profile from the DUP is less than 20% at ρ ⩽ 0.8, and for the MUP, it is less than 17%. A similar picture is observed for the profiles of T e and n e/√T e. An auxiliary heating, P aux ⩾ 1 MW or 10 MW, was present at, respectively, 44% and 21% of the total duration of the flat-top stage of discharges. It is shown that large, ∼100% in magnitude, jumps of T e at ρ = 0, caused by the switch-on of auxiliary heating, can be described with a ∼20% accuracy by the jumps of the space-averaged temperature if the DUP is used to describe the stationary shape of the temperature spatial profile. The results obtained illustrate the degree of plasma self-organization in tokamaks.

Bat bio-assisted sampling (BAS) for monitoring urban heat island

In this study, we demonstrate how urban-dwelling bats can be used to reconstruct Urban Heat Islands (UHI). We term this approach biologically-assisted sampling (BAS). We used Egyptian fruit bats to map the spatial air temperature (Tair) profile. To demonstrate the feasibility of using biologically-assisted sampled data set, we run mixed effects and Geographically Weighted Regression (GWR) models to estimate the impact of urban environment on Tair distribution. Our results suggest that vegetation is a very important mitigating factor in Tair. In the winter, we found an average Tair difference of 2–5 °C between densely urban and nearby vegetative/open areas. A distinct UHI spot was identified in the winter, centered on the Ayalon highway. These differences were lower during the summer night, probably due to a pronounced cooling sea breeze effect along the coastline. Our preliminary results also indicate that BAS sampling provide a 3D view of the UHI phenomenon: the change in Tair above the dense urban area was smaller than above the vegetative area. Since the differences in Tair between densely urban and open/green areas are the largest during the night hours, bats can serve as efficient agents to monitor UHI effects, despite the method limitations.

ОПРЕДЕЛЕНИЕ ПОПЕРЕЧНЫХ РАЗМЕРОВ ДЕФЕКТОВ РАССЛОЕНИЯ БИМЕТАЛЛИЧЕСКОЙ ПЛАСТИНЫ ПРИ АКТИВНОМ ТЕПЛОВОМ НЕРАЗРУШАЮЩЕМ КОНТРОЛЕ

Various methods of nondestructive testing, including active infrared thermography, are used to detect latent subsurface defects in the contact of layers in multilayer products. One of the main difficulties using this method consists in processing and interpreting the thermal image data. The peculiarity of investigated defects of bimetal plate layers continuity violation is that the depth of defect location is known and the main task is to determine its size. Some methods are used for this purpose including analysis of spatial temperature profiles. Aim. To analyse the use of various approaches to determining the transverse dimensions of a delamination between metals in simulating active thermal non-destructive testing of steel-aluminium plates. Materials and methods. Mathematical and computer simulating methods, numerical differentiation are used. The delamination size is determined by projections of half the height of the amplitude signal and the extremum of the derivative of the temperature signal function. Calculations and graphical constructions are performed using the mathematical package GNU Octave. Results. Numerical simulation is carried out for different values of heat flow power, heating and cooling time. The temperature signal distribution over the surface of a multilayer bimetallic plate has been plotted. The values of the defect radius according to the projections of the characteristic points are determined. Conclusion. The results of simulation allow us to conclude that using the projection of the extremum of the temperature signal derivative function allows us to accurately estimate the defect size, while in the case of the point projection cor¬responding to half of the signal amplitude height, the result is underestimated. The obtained results can be used for further experimental studies of processes of active thermal non-destructive testing of products made of multilayer bimetallic materials.

Uniform plasma generation with filament assisted DC discharge in a linear plasma device

Uniform and quiescent (δ n/n < 0.5%) laboratory plasma has been produced in a linear plasma device with a simple filament-assisted DC source without using any magnetic field for plasma confinement. A filament-assisted DC plasma source has been designed, fabricated in-house, and operated successfully to achieve the desired plasma parameters. A stainless steel(ss)-grid is placed in-front of the filament assembly and biased appropriately using a DC-regulated power supply to accelerate thermionically emitted electrons from the heated filaments along the length of the main chamber and facilitate the production of uniform plasma. Heating of the filaments was done by passing a current of ∼3.8 − 4.2 A through it using another DC-regulated power supply. 2-dimensional spatial profiles of plasma density (n e ), electron temperature (T e ) and plasma potential (V P ) obtained from the Langmuir Probe measurements by inserting 4 number of Langmuir Probes inside the plasma from 4 co-linear radial ports of the plasma chamber and scanning them radially with the help of indigenously built probe drive setups reveal spatially uniform plasma generation with n e in the range ∼(1 − 2) × 1015 m−3 and T e ∼ (2.5 − 3.5) eV. Variations of plasma parameters and its spatial uniformity with neutral pressure are also investigated. It is observed that the spatial uniformity of the plasma produced at neutral pressures in the range of ∼(3 − 6) × 10−4 mbar is very good with δ n/n < 0.5%.

A pre-time-zero spatiotemporal microscopy technique for the ultrasensitive determination of the thermal diffusivity of thin films.

Diffusion is one of the most ubiquitous transport phenomena in nature. Experimentally, it can be tracked by following point spreading in space and time. Here, we introduce a spatiotemporal pump-probe microscopy technique that exploits the residual spatial temperature profile obtained through the transient reflectivity when probe pulses arrive before pump pulses. This corresponds to an effective pump-probe time delay of 13ns, determined by the repetition rate of our laser system (76MHz). This pre-time-zero technique enables probing the diffusion of long-lived excitations created by previous pump pulses with nanometer accuracy and is particularly powerful for following in-plane heat diffusion in thin films. The particular advantage of this technique is that it enables quantifying thermal transport without requiring any material input parameters or strong heating. We demonstrate the direct determination of the thermal diffusivities of films with a thickness of around 15nm, consisting of the layered materials MoSe2 (0.18 cm2/s), WSe2 (0.20 cm2/s), MoS2 (0.35 cm2/s), and WS2 (0.59 cm2/s). This technique paves the way for observing nanoscale thermal transport phenomena and tracking diffusion of a broad range of species.

Plasmonic stimulation of gold nanorods for the photothermal control of engineered living materials

Engineered living materials (ELMs) encapsulate microorganisms within polymeric matrices for biosensing, drug delivery, capturing viruses, and bioremediation. It is often desirable to control their function remotely and in real time and so the microorganisms are often genetically engineered to respond to external stimuli. Here, we combine thermogenetically engineered microorganisms with inorganic nanostructures to sensitize an ELM to near infrared light. For this, we use plasmonic gold nanorods (AuNR) that have a strong absorption maximum at 808 nm, a wavelength where human tissue is relatively transparent. These are combined with Pluronic-based hydrogel to generate a nanocomposite gel that can convert incident near infrared light into heat locally. We perform transient temperature measurements and find a photothermal conversion efficiency of 47 %. Steady-state temperature profiles from local photothermal heating are quantified using infrared photothermal imaging and correlated with measurements inside the gel to reconstruct spatial temperature profiles. Bilayer geometries are used to combine AuNR and bacteria-containing gel layers to mimic core-shell ELMs. The thermoplasmonic heating of an AuNR-containing hydrogel layer that is exposed to infrared light diffuses to the separate but connected hydrogel layer with bacteria and stimulates them to produce a fluorescent protein. By tuning the intensity of the incident light, it is possible to activate either the entire bacterial population or only a localized region.

Bio-based insulation materials and model predictive control of active cooling systems in machine tools

The adoption of biological principles and materials plays a decisive role in the conversion to sustainable production technologies. Measures for the biological transformation of a machine tool were implemented following the example of warm-blooded animal, which automatically control their core temperature and, depending on their habitat, possess an insulating layer of fat. In this work, thermal insulation measures were implemented on machine tools using renewable materials and their effects were evaluated.Insulation materials of petrochemical origin such as polystyrene (Styrofoam) were replaced by alternatives made of mycelium with comparable heat insulating properties. On the lower machine bed, a slowdown of the cooling rate was observed after application of insulation materials at external temperature drops. The insulation between the machine bed and the control cabinet was also found to reduce tool centre point (TCP) displacement. This cost-efficient measure reduces the error during the process and the effort required to correct the linear axes and to heat and cool the machine.To homogenize the temporal and spatial temperature profile of machine tools, a control system was developed to compensate for thermally induced errors by means of adaptive active cooling. Therefore, a model predictive control using an embedded artificial intelligence (AI) model to forecast the structural temperature development was implemented. Through a hybrid training database combining experimental and simulative data series, a both flexible and precise determination of the thermal system behaviour could be achieved. On a real production machine, the active cooling system is divided into five individually controllable and adjustable cooling circuits. This approach allows cooling the machine structure according to time and local demand to minimize thermally induced TCP displacement under variable operating conditions.This paper serves to define and evaluate possibilities and requirements for the integration of bio-based insulation materials and control algorithms for homoiothermic conditions in production machines.

Thermo-Visco-Elastometry of RF-Wave-Heated and Ablated Flesh Tissues Containing Au Nanoparticles.

We report non-contact laser-based Brillouin light-scattering (BLS) spectroscopy measurements of the viscoelastic properties of hyperthermally radiofrequency (RF)-heated and ablated bovine liver and chicken flesh tissues with embedded gold nanoparticles (AuNPs). The spatial lateral profile of the local surface temperature in the flesh samples during their hyperthermia was measured through optical backscattering reflectometry (OBR) using Mg-silica-NP-doped sensing fibers distributed with an RF applicator and correlated with viscoelastic variations in heat-affected and ablated tissues. Substantial changes in the tissue stiffness after heating and ablation were directly related to their heat-induced structural modifications. The main proteins responsible for muscle elasticity were denatured and irreversibly aggregated during the RF ablation. At T &gt; 100 °C, the proteins constituting the flesh further shrank and became disorganized, leading to substantial plastic deformation of biotissues. Their uniform destruction with larger thermal lesions and a more viscoelastic network was attained via AuNP-mediated RF hyperthermal ablation. The results demonstrated here pave the way for simultaneous real-time hybrid optical sensing of viscoelasticity and local temperature in biotissues during their denaturation and gelation during hyperthermia for future applications that involve mechanical- and thermal-property-controlled theranostics.

Development of multichord ion Doppler spectroscopy system for toroidal flow measurement of field-reversed configuration.

A double-chord ion Doppler spectroscopy (IDS) system was developed to measure the ion temperature and flow velocity of field-reversed configuration (FRC) plasmas in the FRC amplification via a translation-collisional merging (FAT-CM) device. Adopting a Czerny-Turner mount monochromator and 16-channel photomultiplier tube array, the developed IDS system achieves high wavelength resolution and fast time response. In addition, two vertically aligned optical paths share the optical system up to the monochromator and then branch just before the detector, successfully reducing crosstalk to <1%. The Doppler broadening was measured at two measurement points in the FAT-CM device, simultaneously, and ion temperatures of ∼50eV were measured. Toroidal spin-up from 7 to 15 km/s and a steady flow velocity of ∼10 km/s were estimated from the Doppler shift obtained by the developed system. The observation of the toroidal flow velocity and the spatial profile of the ion temperature of the FRC plasma in the FAT-CM device were realized. These spectroscopic diagnostic's double chord capabilities will aid in understanding and improving the FRC plasmas.