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International Journal of Thermophysics
Journal Prestige (SJR): 0.417 ![]() Citation Impact (citeScore): 1 Number of Followers: 7 ![]() ISSN (Print) 1572-9567 - ISSN (Online) 0195-928X Published by Springer-Verlag ![]() |
- Thermal Diffusivity of Solid and Liquid 304 Stainless Steel, Iron, and
Zirconium-
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Abstract: Abstract Measurement of the thermophysical properties of liquid metals is a highly challenging task due to numerous problems encountered above the fusion point. Properties such as density and surface tension have been widely investigated, while few studies address thermal diffusivity. In this paper we describe an original methodology for estimating the thermal diffusivity of metals in the liquid state. The proposed experimental setup is based on the traditional flash method. Its design ensures that samples of liquid metal are self-contained, preventing contamination and allowing measurements at high temperature. Results for both solid and liquid iron and 304 stainless steel are presented and compared to data suggested by the literature for validation. Then, for the first time, thermal diffusivity measurement of liquid zirconium is performed giving results up to 2450 K. Giving the high sensitivity of the results to the thickness variation we propose a numerical approach to deal with this issue.
PubDate: 2024-08-27
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- Development of A Simple 1-T Dew-Point Generator
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Abstract: Abstract A single-temperature-based dew-point generator (DPG), capable of producing air with dew point temperatures ranging from 25 °C to 60 °C, has been developed at SNSU-BSN Indonesia. The air flows through the saturator in a single pass and is controlled by a flow meter to have a maximum flow rate of 1 lpm. The air saturation process is carried out using a bubble aerator capable of producing bubbles ranging in size from below 0.5 mm to several mm in diameter. A heat sink, placed inside the saturator, is used to prevent water splashes from entering the gas outlet and to stabilize the dew point temperature. The impact of the saturator load is also modeled and simulated. The saturator is then placed into a thermostatic bath where heating of the gas outlet tube is performed starting from 5 cm below the water surface to prevent condensation due to environmental temperature influences. This developed saturator system is simple and low cost. The performance test includes a comparison with a high-precision dew-point hygrometer (DPH) and an evaluation of saturator efficiency. The accuracy of the generated dew point temperature is determined by referencing the reference value from the APMP.T-K8 comparison results. The test results are presented in graphical and tabular format along with an example uncertainty budget.
PubDate: 2024-08-27
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- Demonstration of Thermal Property Determination for a Suspended Wire Using
3ω Method Acquired by a High buffered Multimeter Applying a Discrete
Fourier Transformation and a Window Function-
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Abstract: Abstract In this study, a technique to estimate the thermal properties of a suspended copper wire using the 3ω method was proposed and its operation was demonstrated. This approach used a digital multimeter with a large measurement buffer to implement a procedure in which an appropriate window function and a discrete Fourier transform (DFT) were applied. This significantly reduces the noise level to a few nV, especially in the lower-frequency regions (less than 1 Hz), even if a longer measurement time is required. The third-harmonic voltage signal containing the thermal properties information for the 3ω method was clearly observed with a high signal-to-noise (S/N) ratio, and the thermal conductivity and diffusivity were estimated from 60 K to 300 K from the current frequency dependence of the third-harmonic voltage. The thermal conductivities of the copper wire were determined to be 423.0 and 385.9 W/mK at 100 and 300 K, respectively. Specific heat was calculated from thermal conductivity and diffusivity, and the Debye temperature was estimated to be 346 K from the temperature dependence of the specific heat. These values were in good agreement with previous research. Measurement of thermal properties using a digital lock-in amplifier with identical configuration resulted in overestimation of thermal conductivity in entire temperature regions owing to a low S/N ratio throughout the analysis of the DFT. The technique based on DFT with a window function is therefore more reliable for detecting the third-harmonic voltage in the low-frequency region of less than 1 Hz because it obtains a high S/N ratio.
PubDate: 2024-08-19
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- Analyzing Heat Transfer: Experimental and Theoretical Studies on Metal
Oxide-Based Binary Nanofluid in Mini Hexagonal Tube Heat Sink-
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Abstract: Abstract The research aimed to explore the thermal performance of a miniature hexagonal tube heat sink (MHTHS) by utilizing three different binary nanofluids. These nanofluids incorporated nanoparticles such as MgO, Al2O3, and CuO, dispersed in base fluids of de-ionized water (DIW) (80 %) and ethylene glycol (EG) (20 %) at different concentrations (0.5 vol %, 1.0 vol %, 1.5 vol %, and 2.0 vol %). Variations in volume flow rate (VFR) and temperature spanned from 10L/h to 50L/h and 10 °C to 50 °C, respectively. Throughout the study, nanofluids circulated through the hexagonal tube side (HTS) at VFR ranging from 10L/h to 50L/h, while hot DIW flowed through the mini passage (MPS) at a constant VFR of 30L/h. Notably, CuO–DIW/EG nanofluid exhibited an 8.7 % increase in density, and MgO–DIW/EG nanofluids demonstrated a 14 % increase in thermal conductivity at a particle concentration of 2.0 vol %. However, at a higher particle concentration of 2.0 vol %, MgO–DIW/EG nanofluids exhibited a 5.6 % decrease in specific heat. Furthermore, MgO–DIW/EG nanofluids displayed a 79.6 % increase in heat transfer coefficient and a 66.7 % increase in Nusselt number. Although the pumping power and friction factor showed 5.1 % to 20.4 % and 7.5 % increases in particle concentration and Reynolds number, this negative impact did not affect the overall thermal performance of the heat sink. Finally, the study determined that MgO–DIW/EG nanofluid stands out as the most suitable heat transfer fluid for the heat sink.
PubDate: 2024-08-19
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- Correlations for the Viscosity and Thermal Conductivity of Tetrahydrofuran
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Abstract: Abstract We present hybrid predictive-correlative engineering correlations for the calculation of the viscosity and thermal conductivity of tetrahydrofuran (THF) in the fluid phase. They incorporate critically evaluated experimental data where available, and predictive methods in regions where there are no data and can be applied over the gas, liquid, and supercritical phases. The viscosity correlation is validated from 195 K to 353 K, and up to 30 MPa pressure, while the thermal conductivity is validated in the temperature range 174 K to 332 K, and up to 110 MPa pressure. Both correlations are designed to be used with a recently published equation of state that extends from the triple point to 550 K, at pressures up to 600 MPa. The estimated uncertainty (at a 95 % confidence level) for the viscosity is 10 % for the low-density gas (up to atmospheric pressure), and 6 % for the liquid at temperatures up to 353 K and pressures up to 30 MPa. For thermal conductivity, the expanded uncertainty is estimated to be 15 % for the low-density gas, and 2 % for the liquid phase from the triple-point temperature to 330 K at pressures up to 15 MPa, rising to 4 % at 110 MPa. Due to the extremely limited data available, these correlations should be considered preliminary until further experimental data become available.
PubDate: 2024-08-17
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- Solubilities of Hydrogen, Nitrogen and Carbon Dioxide in the Eutectic
Mixture of Diphenylmethane and Biphenyl-
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Abstract: Abstract In this study, the solubilities of hydrogen (H2), nitrogen (N2), and carbon dioxide (CO2) in the eutectic mixture of diphenylmethane (1) and biphenyl (2) with mass fraction w1 = 0.64947 were determined by the isochoric saturation method at pressures ranging from 0.918 MPa to 6.208 MPa, and temperatures ranging from 293 K to 363 K. The results indicate that the solubilities of the gases in the eutectic mixture follow the order CO2 > H2 ≈ N2. The gas solubility data were correlated using the Krichevsky-Kasarnovsky (K-K) equation. The absolute average relative deviations (AADs) of the experimental values from the calculated data for the H2 + eutectic mixture, N2 + eutectic mixture, and CO2 + eutectic mixture systems were 1.98 %, 1.74 %, and 1.74 %, respectively. Henry’s constants for the dissolution of the three gases in the eutectic mixture at different temperatures were calculated. Finally, thermodynamic parameters (the solution enthalpy, solution Gibbs free energy, solution entropy, and solution specific heat capacity) were calculated and discussed.
PubDate: 2024-08-17
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- Optical n(p, T90) Measurement Suite 3: Results at $$\lambda =
1542\,\text{nm}$$-
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Abstract: Abstract Single-isotherm n(p, T90) results are reported for the gases Ar, N2, H2O, and D2O at vacuum wavelength \(\lambda = 1542.383(1)\) nm. The argon and nitrogen isotherms were measured near 303 K; the water isotherms were measured near 373 K. Combined with the two previous articles of this series, the present results beget several insights via dispersion analyses. The argon result is highly consistent with static measurement plus ab initio calculation of dispersion polarizability. The nitrogen result is nominally consistent with one recent experiment and the dipole oscillator strength distributions, but the present work offers a refined estimate of the molar refractivity at optical wavelengths. For ordinary and heavy water, the dispersion trend is nominally consistent with existing liquid measurements. However, water’s absorption features in the near-infrared preclude a reliable comparison of the present result with literature.
PubDate: 2024-08-03
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- Vibrating-Wire Viscometry
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Abstract: Abstract The theory and application of the vibrating-wire technique for the measurement of viscosity, as well as both viscosity and density, are reviewed. Theory is presented in the form of practical working equations and well-established limitations on their ranges of validity. The cases of both transient and steady-state excitation of the vibrating wire are considered in detail. For the steady-state mode, we describe a variant of the method in which the density is also measured. Practical details including wire materials, magnet systems and instrumentation are discussed, and several design examples from the literature are reviewed. Relative uncertainties in vibrating-wire viscometry vary from, at best, 0.2 % to about 2 % at 95 % confidence. In an appropriately designed instrument, density can be measured simultaneously with a relative uncertainty of about 0.2 %.
PubDate: 2024-08-03
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- Capillary Viscometry for Routine Measurements of Newtonian Liquids
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Abstract: Abstract Viscosity is a thermophysical property of paramount importance, being essential for many scientific and industrial applications. The most common instruments for its measurement are glass capillary viscometers. Therefore, the use of capillary viscometers is widespread both in industry and in research. The range of viscosities of interest range from lower than that of water to several orders of magnitude higher values, the measurement of which requires different capillary viscometers. Most of the practical applications concern routine instruments, mainly for quality control. One main issue for the utilization of capillary viscometers relates to the need for their calibration, assuring its traceability to the water primary viscosity standard, to certify its worldwide validity. The present paper focuses on capillary instruments dedicated to perform viscosity measurements on Newtonian organic liquids at atmospheric pressure, as it is assumed that is the most widespread type of application for these viscometers. Capillary viscometry has a completely well-defined working equation, namely, the Hagen–Poiseuille equation. However, the practical performance of the measuring instruments deviates from that working equation. Most of those deviations are currently considered by many users. However, some of those deviations have not reached that status yet, like those concerning the effects due to the surface tension of the sample on the measurements. All these aspects are summarized and analyzed in the present article, together with a brief general description of the most common types of capillary viscometers, namely, the Ostwald and the constant-level or Ubbelohde instruments.
PubDate: 2024-07-30
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- Viscosity of Hydrogen and Methane Blends: Experimental and Modelling
Investigations-
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Abstract: Understanding of thermophysical and transport properties of H2-NG blends are needed for the gradual introduction of hydrogen into the national gas grid. A capillary tube viscometer was used to measure the viscosity of hydrogen + methane blends (with hydrogen mole fraction = 0, 0.1000, 0.1997, 0.5019, and 1) at temperatures from 213 to 324 K and pressures up to 31 MPa. A total 147 experimental viscosity measurements were made for the three H2 + CH4 blends and compared against the predictions of five different viscosity models: a one-reference corresponding states (Pedersen) model, a two-reference corresponding states (CS2) model, an extended corresponding states (ECS) model, a corresponding states model derived from molecular dynamic simulations of Lennard Jones (LJ) fluids, and a residual entropy scaling (SRES) method. All the model predictions showed a relatively low deviation compared to the measured viscosities. The density required for viscosity model predictions were computed using Multi-Fluid Helmholtz Energy Approximation (MFHEA) equations of state (EoS). To check the experimental procedure and applicability of the viscometer equipment, viscosity validation measurements were carried out for propane, hydrogen, and methane. The measured viscosities of the pure components were in good agreement with the respective viscosity models with AARD of 0.24%, 0.25%, and 0.58% for propane, hydrogen, and methane, respectively. Graphical
PubDate: 2024-07-30
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- Solid–Liquid Phase Equilibrium of the n-Nonane + n-Undecane System for
Low-Temperature Thermal Energy Storage-
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Abstract: Abstract The current article presents an exploration of the solid–liquid phase diagram for a binary system comprising n-alkanes with an odd number of carbon atoms, specifically n-nonane (n-C9) and n-undecane (n-C11). This binary system exhibits promising characteristics for application as a phase change material (PCM) in low-temperature thermal energy storage (TES), due to the fusion temperatures of the individual components, thereby motivating an in-depth investigation of the solid–liquid phase diagram of their mixtures. The n-nonane (n-C9) + n-undecane (n-C11) solid–liquid phase equilibrium study herein reported includes the construction of the phase diagram using Differential Scanning Calorimetry (DSC) data, complemented with Hot–Stage Microscopy (HSM) and low-temperature Raman Spectroscopy results. From the DSC analysis, both the temperature and the enthalpy of solid–solid and solid–liquid transitions were obtained. The binary system n-C9 + n-C11 has evidenced a congruent melting solid solution at low temperatures. In particular, the blend with a molar composition xundecane = 0.10 shows to be a congruent melting solid solution with a melting point at 215.84 K and an enthalpy of fusion of 13.6 kJ·mol–1. For this reason, this system has confirmed the initial signs to be a candidate with good potential to be applied as a PCM in low-temperature TES applications. This work aims not only to contribute to gather information on the solid–liquid phase equilibrium on the system n-C9 + n-C11, which presently are not available in the literature, but especially to obtain essential and practical information on the possibility to use this system as PCM at low temperatures. The solid–liquid phase diagram of the system n-C9 + n-C11 is being published for the first time, as far as the authors are aware.
PubDate: 2024-07-30
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- Exploring Structure–Property Relationships in Eucalyptol and 1-Alkanol
Mixtures: A DFT and Experimental Study-
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Abstract: Abstract This study employs a combined experimental and theoretical approach to investigate the thermophysical properties of eucalyptol (EC) blended with a series of 1-alkanols (ranging from 1-hexanol to 1-nonanol) across a temperature spectrum of 293.15–323.15 K. Density Functional Theory (DFT) calculations at the M05-2x/6-31g(d,p) level of theory are used to optimize the geometry of EC + 1-alkanols and provide insights into the hydrogen bonding interactions between the molecules. The DFT results reveal the significance of alkyl chain length in 1-alkanols on the hydrogen bonding with EC, which is supported by the analysis of geometrical, topological properties, vibrational frequency, NMR, and molecular orbital analysis. The theoretical findings are complemented by experimental measurements of density and viscosity, which show negative deviations from ideality in excess molar volume and viscosity. This study highlights the power of DFT methods in elucidating the molecular-level interactions governing the thermophysical properties of complex binary systems. Furthermore, the DFT results provide a molecular-level understanding of the observed thermophysical behavior, allowing for the development of more accurate predictive models. The integration of experimental and theoretical approaches in this study demonstrates a powerful framework for investigating the properties of complex mixtures.
PubDate: 2024-07-30
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- Enhancing Air Conditioning System Performance via Dual Phase Change
Materials Integration: Seasonal Efficiency and Capsulation Structure
Impact-
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Abstract: Abstract Enhancement of the cooling and heating capabilities of an air conditioning unit (ACU) coupled with a thermal energy storage system of dual phase change materials (PCM) is investigated. The dual PCM, namely SP24E and SP11_gel, are coupled with the ACU outdoor device (condenser/evaporator) during the summer/winter seasons, respectively. Moreover, ACU performance assisted with dual-PCM heat exchanger is compared with a single heat exchanger of SP24E in summer and single heat exchanger of SP11_gel in winter at different PCM capsulation structures (aligned and staggered cylinders). The system dynamic mathematical model is computationally solved using ANSYS software and experimentally validated. Results affirm that charging/discharging periods are minimal for the dual-PCM system and slower for PCM inline cylinder layouts than staggered ones. Inline design yields greater ACU average power savings. In summer, higher inlet air temperature to the PCM system reduces PCM discharging time and ACU power savings, with the opposite effect during winter. ACU COP with PCMs is improved by around 80 % in summer and 40 % in winter, respectively, compared to ACU without PCMs. The maximum average power saving over 4 h of ACU working in summer by single and dual-PCM systems is 21.4 % and 11.8 %, respectively, whereas the results in winter are 18.5 % and 12.8 %, respectively.
PubDate: 2024-07-29
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- Thermal Properties of Some Molten Mixtures in System (NaF-KF)eut–UF4
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Abstract: Abstract The thermophysical properties of molten salts promising for the nuclear industry are crucial, but the available data are limited and contradictory. The thermal diffusivity of the molten mixtures (NaF-KF)eut–UF4 containing 30, 40, and 50 mol % UF4 was measured by the laser flash method. The thermal diffusivity was found to be almost independent of temperature in the range of about 100° (1070 K–1170 K), which makes it possible to extrapolate values to low or high temperatures. The thermal conductivity of the molten mixtures (NaF-KF)eut–UF4 was calculated using the thermal diffusivity, density, and heat capacity data. Density was estimated using the molar volume of the molten binary systems NaF-UF4 and KF-UF4. The heat capacity of the ternary system NaF-KF-UF4 was evaluated based on the heat capacity of individual salts, taking into account the additivity law. The thermal conductivity of the molten mixtures 0.7(NaF-KF)eut–0.3UF4, 0.6(NaF-KF)eut–0.4UF4, and 0.5(NaF-KF)eut–0.5UF4 changes slightly with the UF4 content and temperature; for example, at 1123 K it is 0.48, 0.45, and 0.45 W·m−1·K−1, respectively. The thermal diffusivity of the pure molten UF4 was estimated using three independent approaches: the concentration, the temperature, and the volume dependences of the thermal diffusivity. The estimated value of the thermal diffusivity for the molten UF4 was about 0.12 × 10–6 ± 0.05 × 10–6 m2·s−1.
PubDate: 2024-07-23
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- Enhancing Solar Photovoltaic System Efficiency: Recent Progress on Its
Cooling Techniques-
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Abstract: Abstract There is a paradox involved in the operation of photovoltaic (PV) systems; although sunlight is critical for PV systems to produce electricity, it also elevates the operating temperature of the panels. This excess heat reduces both the lifespan and efficiency of the system. The temperature rise of the PV system can be curbed by the implementation of various cooling strategies. These strategies fall under three categories: passive, active, and hybrid cooling, with similar objectives of regulating excess heat generation. Employing heat pipes can be an example of the passive method, while the use of forced circulation of water flow can represent an active method. A combination of energy storage and forced convection represents an example of hybrid cooling. Most of the research has two objectives, one to obtain higher PV efficiency and another to enhance the life span of the system. This review explores various cooling strategies employed by the researchers i.e., heat pipes, heat sink, air or water channels, water spray, use of phase change material, microchannel for coolant passage, thermoelectric (Peltier) modules. In general, for passive cooling techniques, efficiency enhancement of up to 44.12 % was obtained due to the temperature reduction of around 11 °C. In the case of active cooling techniques reported better performance with PV temperature reduction as high as 55 °C. Hybrid cooling also leads to some promising performance improvements. Characteristics and performance of various cooling methods are explained in this review to provide future researchers with valuable insight and direction. This could lead to much better improvements in these cooling techniques in the near future.
PubDate: 2024-07-23
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- Theory and Experiment of the Soret Forced Rayleigh Scattering Technique
for Mass Diffusion Coefficient Measurement of Binary Liquid Mixtures-
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Abstract: Abstract Mass diffusion coefficient measurement techniques with high temporal and spatial resolution have become essential for the research and development of leading-edge technology in a wide range of cross-disciplinary fields, but cannot be achieved using conventional methods. We provide a comprehensive review of the state-of-the-art theoretical and experimental investigations on Soret forced Rayleigh scattering (SFRS), a grating excitation technique (GET) for measuring the mass diffusion coefficient of binary liquid mixtures. SFRS utilizes the Soret effect to create micrometer-order periodic spatial concentration modulation in a sample due to the absorption of an optical interference grating generated by two intersecting heating laser beams. The decay of the concentration modulation by the mass diffusion process within several milliseconds is detected by the diffraction of a probing beam. The theoretical considerations regarding deviations from the ideal mass diffusion conditions are the effects of: (1) the Gaussian beam intensity distribution, (2) the light absorbing material and (3) the cell wall. The proper settings for the optical system are also analyzed, e.g., the effect of coherency and polarization of the heating laser and the effect of the z-direction length of the interference region. We also consider the frame of reference, center of gravity invariance and effect of convection, which are particularly important for mass diffusion experiments. Using the correct implementation of the theory, the optimal SFRS apparatus design and its appropriate use are described in detail. Finally, two successful applications of SFRS are demonstrated using visible light laser heating and mid-wavelength infrared gas laser heating.
PubDate: 2024-07-17
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- Study on Temperature Noise Suppression Characteristics Based on Multilayer
Composite Structure-
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Abstract: Abstract The noise caused by various temperature effects in the sensitive frequency band will cause errors in the detection results of space gravitational wave. Therefore, it is important to suppress the temperature noise of space-borne gravitational wave detectors. In this paper, a method is proposed to suppress temperature noise using a multi-layer composite structure consisting of low thermal conductivity material (R) and high specific heat capacity material (C). The arrangement in which heat flow passes through high specific heat capacity material first is “CR.” The thermal simulation model is established to study the temperature noise transfer characteristics, and accuracy of the model is verified by experiments. The results show that the temperature noise of CRC is 90 % lower than that of RCR. The arrangement which heat flow passes through high specific heat capacity material first has an optimal high specific heat capacity material’s proportion of 60 % to 70 %. When the number of composite layers is not less than 3 layers, the more the composite layers’ number is, the better the suppression effect of multi-layer composite structure on temperature noise is. However, there is a limit to the way of obtaining noise reduction effect by increasing the number of layers. This paper provides a guidance for the suppression of temperature noise in gravitational wave detection.
PubDate: 2024-07-11
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- The Influence of Excess Free Carriers as Heat Carriers on the n-Type
Silicon Thermoelastic Photoacoustic Responses Explained by
Electro-Acoustic Analogies-
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Abstract: Abstract The explanation of the n-type silicon thermoelastic photoacoustic response is given by electro-acoustic analogies, which clarify the influence of excess free carriers as heat carriers. It was found that electro-acoustic analogies could interconnect different theoretical models of heat flow and carrier dynamics aiming to find the optimal experimental conditions for the efficient free carrier influence analysis of the sample thermoelastic photoacoustic response. Theoretical analysis was based on the comparison between the composite piston, surface recombination, and RC filter frequency response models, extrapolating the behavior of the photoacoustic response much beyond the experimental frequency domain. Experimental analysis was based on the open-cell photoacoustic setup operating under the transmission configuration within the modulation frequencies range from 20 Hz to 20 kHz. The accuracy of our predictions and the validity of electro-acoustic analogies are confirmed by measuring 875 μm plasma-thick and 35 μm plasma-thin silicon samples.
PubDate: 2024-07-11
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- High-Pressure Density of Eutectic Mixtures Containing dl-Menthol and
Acetic Acid-
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Abstract: Abstract The eutectic mixtures consist of dl-menthol and acetic acid were prepared at five molar ratios (3:1, 2:1, 1:1, 1:2, 1:3). The vibrating-tube densimeter was used to measure the density of the DL-menthol/acetic acid mixtures, and the measurements were carried out from 293.15 K to 363.15 K and pressures from 0.1 MPa to 70 MPa. The measured densities of each dl-menthol/acetic acid mixture at different temperature and pressure were correlated by the Tait equation. In addition, the derived properties of dl-menthol/acetic acid mixtures including isothermal compressibility, isobaric thermal expansivity, and internal pressure were calculated. The effects of temperature, pressure, and molar ratios on the derived properties were compared and analyzed.
PubDate: 2024-07-11
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- Gas Pressure-Dependent Thermal Conductivity Measurements of Bimodal
Xerogels-
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Abstract: Abstract Measurements of the thermal conductivity were performed as a function of gas pressure from 10–1 hPa up to 105 hPa on several bimodal silica xerogels. The xerogels exhibit a mesopore and a macropore phase. The measurements were done using a hot-wire apparatus, which can do automated, gas pressure-dependent measurements of the thermal conductivity from 10–3 up to 105 hPa. Results were fitted with a bimodal gas pressure-dependent thermal conductivity model to gain information on the thermal conductivity of the materials, its various contributions and on structural parameters such as the two main pore sizes, the macro- and mesoporosities. The pore sizes and porosities were compared to values gained from mercury porosimetry and nitrogen adsorption measurements. The porosities from the thermal conductivity measurements are in very good agreement to the other measuring methods. The macropore sizes from the thermal conductivity measurements are mostly in agreement within the given uncertainty range and the mesopore sizes show a good estimate of the order of magnitude of the pores.
PubDate: 2024-07-11
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