Heat transfer and pressure drop in mini-channels were examined by using water. The cross-section tested was rectangular. The width, height and length of the flow channel were 3 mm, 0.203 mm 〜 0.791 mm and 260 mm including the heating length of 50 mm, respectively. When the flow channel height became shorter than 0.401 mm, the heat transfer coefficient and the pressure drop coefficient of water single phase flow became smaller than those predicted with correlations for the usual size flow channel. The heat transfer coefficient showed dependency on the Reynolds number in the low Reynolds number region. The pressure loss coefficient did not show transition from the laminar flow to the turbulent flow in the high Reynolds number region.

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Microscopic heat transfer characteristics of boiling in a mini-channel are investigated by the local surface temperature measurement with a MEMS thermal sensor and a high speed observation of boiling behavior in the mini-channel. The heat transfer phenomena included in the elongated bubble boiling were identified from the experimental results. The local wall surface heat transfer was calculated by one-dimensional transient heat conduction analysis with measured wall temperature data as a boundary condition. The initial microlayer thickness and the amount of the evaporated microlayer were evaluated with the local heat flux. The dimensionless initial microlayer thickness increased with Capillary number corresponding to the ratio of the viscous force and the surface tension.

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An experimental apparatus were developed to investigate local heat transfer on a rotating hollow cylinder during laminar jet cooling. The experiments were performed for an extensive range of cooling conditions such as water flow rate and liquid subcooling. Tested material of the cylinder was stainless steel (SUS304) and its dimensions were 136 mm in outer diameter, 150 mm in height and 10 mm in thickness. Using a similarity law for transient heat conduction in thick stainless steel and thin hot strip walls, we specified a rotational speed of the cylinder as 30 rpm. Growth of wetted area around the stagnant point was observed for initial temperature 800℃ and local surface temperature and surface heat flux changes were measured.

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In this study, effects of the droplet flow density and mean droplet diameter on film boiling heat transfer and collapse temperature of film boiling (MHF point temperature) of spray nozzle cooling were examined experimentally. A test heater was Nichrome foil with 0.2 mm thickness, 5 mm width and 100 mm length. The droplet flow density was 50, 100 and 200 l/min m^2, respectively. The mean diameter of droplet was 198, 301, 352, 415 and 472μm, respectively. The test heater was heated by DC current through DC power supply. The temperature of test heater was measured by using a K-type thermocouple. The present experimental results showed that film boiling heat transfer increased with increasing mean droplet diameter. The effect of the mean droplet diameter on MHF point temperature was weak. On the other hand, film boiling heat transfer and MHF point temperature increased with increasing droplet flow density. The correlations were obtained for film-boiling heat transfer and MHF-temperature.

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Bubbly flows are found in a lot of industrial fields such as power and chemical plants and water purification system. PIV is useful tool to investigate the bubble motion and flow structure in the liquid phase simultaneously. In the present study, we have developed velocity measurement system of solid-gas-liquid three phase flow by phase discrimination using interferometric imaging of scattered light. We applied this system to microbubble flow, measuring area was about 9.6mm×8.0mm and we could discriminate the bubbles from the solid tracers within a range of ±1mm from the focal plane. Moreover, bubbles going up and solid tracers settling out were captured. From these results, it is concluded that this system can be applied successfully to measurement of the velocity distribution of three phase flows.

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Instantaneous velocity profiles of liquid and bubbles are important thermal-hydraulic parameters which play essential role in study of heat, mass transfer of bubbly two-phase flow. Using spike signal with control of damping parameter, we have successfully developed a multiwave ultrasonic measurement method to obtain instantaneous velocity profiles of liquid and bubble phase of bubbly two-phase flow. For analysis of echo signals, the ultrasonic pulse repetition method has been exploited. The method is robust and computationally efficient. Moreover, this measurement method enables a significant reduction of expenses by using commonly used, popular spike pulser/receivers of ultrasonic inspection industry. In addition, a phase separation method has also been proposed to completely separate liquid data and bubble data. Measurement has been carried out for bubbly counter-current two-phase flow in a vertical pipe of 50mm I.D. Instantaneous velocity profiles of liquid and bubbles have been measured.

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The authors have proposed a framework of a linear theory for finding inherent resonant states and optimal forced vibration on a given stable thermal convection field, independent of the ways of forced vibration, indicators of resonances and so on. It is based on a dynamical system theory, applicable to capture any resonance states on a stable steady system subject to a forced vibration, not limited to thermal convection fields. However, its applicability is largely dependent on the amplitude of time-varying forcing. It is clarified, in this study, that a weakly nonlinear expression of midplane Nusselt number allows us to identify the effective range of the amplitude. It implies that the weakly nonlinear analyses provide the measure on the effectiveness of the linear theory.

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Liquid film thickness is a key parameter in evaporation and condensation heat transfer in micro tube slug flow. The present work addresses numerical simulation results on the liquid film thickness of gas-liquid slug flow in a micro tube. The Phase-Field method is employed to capture the interface, and the effects of capillary number and the grid size are investigated. The simulated liquid film thickness agrees well with experimental results at higher capillary numbers, but is found to be thicker than that of the experiments at lower capillary numbers. This is because the minimum liquid film thickness reproduced by the Phase-Field is limited by the diffused interface across several grids.

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The effect of initial flow velocities on the liquid film thickness in micro-channel accelerated slug flow under adiabatic condition is experimentally investigated. Laser focus displacement meter was used to measure the liquid film thickness. Distilled water was used as a working fluid. Circular tube with inner diameter of 1 mm and length of 500 mm was used. The effects of the initial steady flow velocities, acceleration, and axial distance were evaluated. As the initial flow velocity increases, the liquid film thickness slightly increases at the constant acceleration and axial distance. The experimentally obtained results were compared to the previous correlation in which initial flow velocity is not considered. For each Bo, the liquid film thickness at small axial distance is deviated from the correlation which becomes large with increasing initial flow velocity. At large Z, the correlation well predicts the liquid film thickness which means that the effect of initial flow velocity is negligible at large Z. Also the deviation becomes significant with increasing Bo. The effect of initial flow velocity should be considered in low Bo and Z.

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Numerical simulation of heat and fluid flow has been performed to clarify the thermal conditions using for transient one-dimensional numerical simulations of a miniature thermoacoustic oscillator. Transient one-dimensional equations of continuity, momentum and energy were solved utilizing a TVD scheme. A simple physical model was used for the numerical simulation. As a result, it was found that the consideration of the other thermal conditions with the input heat conditions that heat is transferred from a heater to working gas and to walls for the numerical analysis of a thermoacoustic oscillator is necessary because both of the behaviors of temperature change and pressure amplitude are different from the experimental results.

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A method to actively enhancing supercooling is one of most promising techniques for cryopreservation. The object of this paper is to study the combined effects of ultrasonic vibration and alternating magnetic field on supercooling of water. In the experiments, water in a tube was cooled at constant cooling rate, and ice-nucleation temperature was measured. Three methods; (a) amplitude-modulated ultrasonic vibration at frequency of 1MHz, (b) alternating magnetic field at frequency of 2kHz, and (c) combined method of (a) and (b) were tested by varying the ultrasonic power and magnetic flux. As the results, it was found that the weak enhancement of supercooling and the decreasing standard deviation of supercooling degree was achieved by combining ultrasonic vibration and alternating magnetic field.

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We report on a direct contact airflow type snowmelt system using exhaust heat, which flows air quasi-uniformly from the surface of the water-and-air permeable concrete block or surface. Two different types of the system have been verified as a reliable snowmelt system through experimental study. One is unit block type, and the other is construction site deposit type. The unit block type has hollow plastic cubic structure under the water-and-air permeable concrete block. The heat source is residential exhausted heat and delivered to the snowmelt site by electric fan. The construction site deposit type has perforated tube under the water-and-air permeable concrete surface. The heat source is taken from sewer manhole inflow which hot spring waste water comes in. Both of the system showed capable performances as snowmelt system at the test site installed in Hokkaido district.

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Winter flounder antifreeze protein is a useful agent to establish technologies for the storage of organs to be transplanted, the preservation of foods and maintaining ice slurry flow. The aim of this study is to clarify the effect of addition of antifreeze protein to ice slurry on flow field. We carried out the measurement of velocity field of ice slurry flow in a mini-channel using particle tracking velocimetry technique. It is found that the solution flow around the clusters of ice particles is noticeable. Furthermore, it is found that the velocity for the cluster of ice particles in the saline solution with the antifreeze protein is lower than that in the saline solution only.

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Ice slurry has the many advantages as phase change material, since the latent heat of fusion of the ice particles can be used and the heat exchange area is very wide. In this study, the heat transfer characteristics of ice slurry are investigated experimentally to examine the effect of some parameters, such as the initial concentration of the aqueous solution and the heating condition. As the results, it was found that the Nusselt number can be expressed as the function of apparent Reynolds number, IPF and the ratio of the average diameter of the ice particles to the diameter of the test tube.

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In this study, the method of generating propane hydrate from propane gas and water was ezamined using nylon sponge. The purpose of this study is to generate more hydrates by using nylon sponge. In the experiment, pressure, temperature, and quantity of water were focused. As a result, hydrate was generated, if the water level does not exceed the height of the nylon sponge. Further, it was found hydrate is generated in a short period of time. The generation speed increases with 'the amount of the water.

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In order to increase the heat capacity of nano and micro satellites, the development of a heat storage material for nano and micro satellites has been performed. It is desirable that the heat storage materials for nano and micro satellites have the characteristic of not phase change but crystal transformation for the heat storage. Trans-1,4-polybutadien transforms crystal structure at the temperature of heat storage. Trans-1,4-polybutadien is produced and the heat storage performance is measured. It is clarified that the produced trans-1,4-polybutadien has 80 J/g of heat storage performance. This value corresponding to 70 % of heat storage performance pointed out in the previous literature.

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Flow and temperature fields of slurry of Al-Si alloy in the process of cup-cast method is numerically simulated. The simulation results agree with the experiment by Shimasaki et al. under an estimated value of the overall heat transfer coefficient between the alloy and the cup.

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Heat switches are devices that switch between good thermal conductors and good thermal insulator. Paraffin actuated heat switches have been developing for the thermal control of the spacecraft. In this study, the controllability of set point temperature (ON/OFF temperature) was evaluated. The results show that it is possible to change set point temperature range by selecting the appropriate paraffin. The effect of the surface finish of touching face on the overall thermal conductance was also evaluated for the purpose of the improvement of the thermal performance. The effect of the surface finish of touching face on the overall thermal conductance was also evaluated for the purpose of the improvement of the thermal performance. The results show that thickness of the coating has the biggest influence on thermal contact conductance.

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Aluminum alloy castings have superior properties that is low-weight, low production energy, Reusability and so on. On the other hand, Electroless nickel plating layer is formed to hard surface by the heat-treatment. We have tried to find the possibilities of the low-cost hybridizing process that make hard surface on the aluminum alloy castings, and we have examined the casting process that combines the aluminum alloy castings with the aluminum base-plate which has the electroless nickel plating layer. As a result, we found the adequate temperature condition of pre-heated mold and molten metal for the hybridizing process.

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The latent heat storage rates of dispersed water drops in W/O (Water/Oil) emulsion are investigated experimentally on this study. The water drops in emulsion has the diameter within 3〜25μm, the averaged water drops diameter is 7.3μm and the standard deviation is 2.9μm. The direct contact heat exchange method is chosen as the phase change rate evaluation of water drops in W/O emulsion. The supercooled temperature and the cooling rate are set as parameters of this study. The evaluation is performed by comparison between the results of this study and the past research. The obtained experimental result is shown that the 35K or more degree from melting point brings 100% latent heat storage rate of W/O emulsion. It was clarified that the supercooling rate of dispersed water particles in emulsion shows the larger value than that of the bulk water.

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In recent years, extensive research of heat storage technology has been conducted for environment improvement. Among them, a research of a phase change material (PCM) has attracted attention as a new energy storage media. The reason for PCM such as the phase change nano-emulsions is that it is possible to disperse by absorbing the latent heat within the range of the phase change temperature. However, the nano-emulsion causes the supercooling when the phase changes. In this report, the supercooling control of the nano-emulsion was examined. Nano-emulsion was consisted of tetradecane, surfactant, and water. A polymer or a nano-particle was used as a nuclear agent. Regarding the fundamental phase change characteristics of the nano-emulsion, it was found that its phase change characteristics were strongly affected by polymer. However, it was not affected by nano-particle.

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The present study is investigated the direct contact solidification behavior between latent heat storage material and heat transfer oil. Purpose of this study is development of a latent heat storage system which is suggested using waste heat of temperature region (100〜200℃) as heat source from factories. Mixture of mannitol and erythritol was adopted as phase change material (PCM). To examine detailed heat exchange behavior, test section was constituted glass tube and the number of nozzle hole for injecting heat transfer oil is one. By this study, the following matters became clear. Size of injected oil droplets rise with the increasing flow of oil. Flow path is different depending on the height direction.

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This paper presents thermophysical properties and dispersibility of some phase change nano-emulsions. The testing emulsions consist of surfactant aqueous solutions and n-hexadecane droplets as the phase change material, which are chemically dispersed in the solutions by means of D-phase emulsification method. Some samples of the emulsions are forced to undergo 10 cycles of melting and solidification process, and their dispersibility, DSC curve, droplet size distribution and viscosity are compared to those of the samples which are statically kept under room temperature. The results reveal that the testing emulsions have pretty stable properties even after they are molten and solidified repeatedly.

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We performed the experiment in Giant Unilamellar Vesicles (GUV)-mass production that utilizes the mechanical oscillation on the silicone substrate with the rehydrated patterned-lipid-layers. The effect of the electric conductivity of rehydrating solution on GUVs' productivity was evaluated by measuring the density and the diameter distribution of GUVs that were produced in an isotonic (300 mOsmol/kg) mixture of D-mannitol (low conductivity) and KCl (or PBS) (high conductivity). It is found that GUVs are produced only by under the flow field, although the productivity of GUV becomes extremely lower as the electric conductivity becomes higher. From these results, we clarify that the electric conductivity and the flow field in the solution are important for the mass-GUY production.

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Microscopic observations of the freezing process of plant leaf cells have been made using a directional solidification stage, in order to study the freezing mechanism of living tissue. Thus, the studies of cooling or freezing cells have been performed. However, the observation of cells around freezing point is not yet. In order to investigate the effect of cell freezing by cytoplasmic streaming, we made a temperature control stage based on directional solidification stage and observed the Egeria densa as aquatic plants. In this study, we reported that we made temperature control stage and observation of cytoplasmic streaming velocity at 5, 10 and 15℃.

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The objective of the present study was to obtain important information for freezing a target tumor down to a given temperature in cryosurgery using the latest 1.5 mm-dia. cryoprobe, Needle I for CryoHit^<TM> system. To this end, freezing experiments were conducted with a tissue phantom made of 0.9 % NaCl aqueous solution gel. The result suggested that an 8-mm margin at the periphery of the ice ball is needed for -40℃ irrespective of the operating gas pressure. It was also demonstrated that the numerical analysis agreed well with the measurement, which indicates the usefulness of numerical simulation for predicting temperatures.

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This study is to evaluate that radiative heating on skin has an effect on physiological response in experiment and numerical analysis. In numerical analysis, temperature of surface and inside of the skin is caluculated by using biological heat transfer equation. In experiment, agar gel is used as simulation sample to estimate a temperature inside the skin. Surface temperature on skin or agar is measured in IRthermometer and thermocouple. As a measured value of IRthermometer is higher than one of thermocouple by the effect of reflection of radiation from high temperature surface, it is revised to be close to the true value.

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In modern societies, stabilization of energy supply and reduction of carbon dioxide (CO_2) emission in the air has been a pressing subject. In order to solve these problems, this study proposes a carbon recycle system which utilizes emitted CO_2 in the air, and converts it into energy. The purpose of the study is to develop a high speed and large quantity cultivation method by using marine biomass as the promotion medium to fix-CO_2. Therefore, the effect of mass transfer to the algae by different water flow was conducted experimentally. Based on the experimental results, the appropriate water flow conditions for high-density cultivation of algae was investigated.

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In order to determine the heat of polymerization of bone cement made mostly from methyl methacrylate polymer, methyl methacrylate - styrene copolymer and methyl methacrylate monomer, the authors polymerized the cement in the building insulation at ambient temperature under atmospheric pressure, and measured both the temperature of the cement θ during the polymerization and the specific heat capacity of the polymerized cement c_<bc>. The experiments were carried out at ambient temperatures θ_<amb> of 17 to 28℃. During the polymerization, the temperature of cement increases transiently to the top temperature θ_<max> and never decreases. The difference ΔT between the cement and ambient temperatures slightly increases with increasing the mass of cement, and it exceeds 88 K. The polymerization reaction takes around 700 sec. The specific heat capacity increases from 1.4 to 2.1 kJ/(kg・K) with increasing the temperature from 28 to 122℃. The heat of polymerization q_0 estimated based on the results of the temperature and the specific heat capacity reaches around 145 J/g. Then the heat loss from the cement samples is estimated to be within 17.9 J/g.

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It was shown by theoretical and experimental studies that high temperature and high pressure state is provided in the converging center by converging shock wave or imploding detonation. In particular, the imploding detonation can implode more effectively than the case of the shock wave. The authors examined the microorganism treatment technique using ultra-high pressure underwater shock waves in a steel pipe by the gas imploding detonation until now. The authors tried to confirm the effect of underwater shock wave generation by change minimum converging radial distance of imploding detonation. As a result, the maximum pressure increased in a decrease in the minimum converging radial distance. Therefore, there was large percent of mortality rate with an increase in minimum converging radial distance.

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Ultra high pressure underwater shock waves were applied to the sterilization of microbes. We used the imploding detonation of propane-oxygen to occur the ultra high pressure underwater shock waves. We investigated the imploding detonation using an engine type liquid sterilization apparatus having a precombustion chamber and two sample holders with inner volume of 5L. This apparatus can work 60〜90 rpm continuously and sterilize the water of 20m^3/h. We investigated the pressure of underwater shock waves relation with engine speed and supplied pressure. We found that we could generate about 40〜60 MPa underwater shock waves in the sample holders.

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We treated sake yeast using ultra-high pressure under water shock waves. As a result, about 84% of sake yeast is killed, it is milled. Furthermore, we investigated the mortality of the remaining individual, using methylene blue staining. We examined with a scanning electron microscope, the change in detailed form. There is an individual that is not stained immediately after treatment. There was also the same individuals form. However, after two weeks, were stained almost 100%. The form was also modified significantly. From the above reasons, the sake yeast was killed by underwater shock waves. It had been stained with methylene blue residual enzymes. The form was changed over time.

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In this study, we numerically calculated the thermal radiative properties from the spoof surface plasmon mode on the Surface Modified Micro-Particle Array. The rigorous coupled wave analysis (RCWA) was used in the calculations. Au thin films in the shape of the surface of Micro-particle Array were made as the calculation models. The structural periods were 2μm, 3μm and 5μm. The calculated absorptance was enhanced in near-infrared in all models. The absorptance peaks of the calculate result were agreed with the analytical model results, and those were appeared in the wavelength vicinity to periodicities of the micro-structures. We conclude that the absorptance in near-infrared can be enhanced by Surface Modified Micro-particle Array.

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MEMS emissivity control device can be expected as a thermal control device for next generation spacecraft. However, there are uncertain matters such as vibration and impact resistance in launch, heat resistance in space environment, and thermo-optical characteristics, due to the micro-scale structures. For clarifying these matters, emissivity control device was fabricated using MEMS shutter array. In this paper, we report the results about effective emissivity of the device by thermal analysis and by calorimetric method.

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A periodic micro structure of the cubic cavity of 6.0μm×6.0μm×6.0μm is built on an ultra violet curable resin by the UV nanoimprint method. A gold film is sputtered on the periodic micro structure. This method can manufacture the periodic micro structure with the metal surface on a large area at a lower cost than etching. It is measured that the maximum normal emissivity of the periodic micro structure is 0.6 near 10μm in the case of the gold film of 200 nm thick on the surface facing a sputter source. The periodic micro structure with the gold film contributes to the prevention of global warming.

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This paper theoretically describes coupling mechanism between spoof surface plasmon (SSP) and radiative field. We calculate absorbance of periodic microcavity array using exact Rigorous Couped-Wave Analysis (RCWA) method and discuss the coupling condition of SSP and incident beams. We derive angular dependence of emittance of thermal radiation and this results show quasi-vertical narrow-band thermal emission from the microcavity array.

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In this study, we tried to measure spectral hemispherical transmittance of piling quartz glass plates with double-layer anti-reflection (AR) coatings in order to verify the spectral control performance for diffuse irradiation. It was revealed that spectral normal transmittance of the filter was reduced with increase in the number of the plates except for the specific narrow wavelength region, where the AR coatings worked ideally. As a result, it was shown that the filter achieved effective spectral control in normal direction for the diffuse irradiation although the coatings were designed for irradiation with polar angle of 45 degree.

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Near-field radiation transfer between pillar-array structured surfaces was investigated numerically. In the case of channels with low aspect ratios, spectral near-field radiation flux has three peaks. It was clarified that the third peak with the highest frequency was originated from an interference of SPP(surface plasmon-polariton) induced at the top surface of the pillar, while the first and the second peak with relatively lower frequency from that at the side wall surface of it.

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Thermal management is crucial for high-functional spacecrafts under rapid temperature fluctuations. Since thermal radiation is the only means for heat removal, active control of radiation is required for advanced space missions. We has proposed MEMS active radiator using the near-field radiation effect. Unlike previous bulky thermal louvers/shutters, higher fill factor can be accomplished with an array of electrostatically-driven micro diaphragms. In this report, an improved prototype for near-field radiation is proposed with a MEMS-based parallel-plate configuration, which enables a submicron gap.

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Waste heat from liquid droplet flow is due to be measured by a part of research of the liquid droplet radiator which is a radiator for large-sized spacecrafts. In order to take the influence of absorption or dispersion into consideration, the simulation inside an experimental device was performed. In the case of the single liquid droplet flow, the energy from the liquid droplet flow in a measuring range was set to 0.252 w/m^2. The energy from the surface of a wall was set to 0.116 w/m2. A possibility of separating the amount of thermal radiation obtained in an experiment was able to be shown.

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This paper presents the visualization of heat and mass transfer of aqueous solutions in microchannels by using the simultaneous imaging method of the temperature and solute concentration. This method is based on the absorption characteristics of water in a near-infrared region: absorbance at a wavelength of 1412 nm is dependent on the temperature whereas that at 1442 nm is independent. This visualization method is applied to experimental researches on chemical reactions between hydrochloric acid and sodium hydroxide aqueous solutions. These two reagents are supplied into two inlets of a Y-shaped rectangular microchannel at several different flow rates. Absorbance difference images in the merging region of the two flows are obtained at the two wavelengths simultaneously, which demonstrate that the magnitude and distribution of the absorbance difference vary with the concentrations and flow rates.

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This paper presents a method of reconstructing the temperature distributions of water around a small heated sphere. This method is based on the temperature dependence of the absorbance of water at the wavelength of 975 nm. Absorbance images at this wavelength were obtained when an iron sphere with a diameter of 1 mm located in water contained in a glass cell with a light path length of 10 mm was heated by a high-frequency magnetic field. Inverse Abel transform was applied to the line profiles of the absorbance, and cross-sectional temperature distributions around the sphere were reconstructed. The temperature distributions vary with the magnitudes of the magnetic field, which indicates the possibility of quantitative evaluation of induction heating systems.

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In the separated and reattachment flow, unsteady heat transfer, which is relative to the flow behavior, is observed near the reattachment point. To clarify the thermal fluctuation, it is necessary to measure simultaneously thermal and flow fields using measurement techniques of the high sensitivity and fast response. The aim of this paper is to construct the simultaneous measurement system, which is able to measure unsteady heat transfer and flow behavior using PIV and high-speed infrared thermography, and to discuss the correspondence to the fluctuations of thermal and flow behavior in the separated and reattachment flow over a backward facing step.

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At the optimum filling the hydrogen into the Fuel Cell Electric Vehicle (FCEV) tank along the standard protocols, one of the important factors is the inlet temperature of the hydrogen. Therefore, it is important to measure the temperature of the inlet hydrogen correctly at the hydrogen station. However, no one indicates that how much error level is included on the temperature measured in the hydrogen refueling station. In this paper, the error of temperature measurement in the hydrogen refueling station is clarified and the calibration equations of the measured temperature are proposed.

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A heat flux measurement method was developed to analyze heat flow on heat radiating surfaces. Thermal resistances made of plastic plates were attached to the surface. The heat flux was obtained by measuring the temperature difference between the radiating surface and thermal resistance surface. The surface temperature was measured using thermography. Unlike conventional heat flux sensors which are made of thermopiles, this method does not require installing wiring. It also enables the multipoint measurement of heat flux. The heat flux measurement method was applied to model evaluation and proved the potential of measuring heat flux distribution.

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We developed an innovative non-contact optical viscosity sensing technique, laser-induced capillary wave (LiCW) using pulsed near-infrared heating laser, to measure liquid food viscosity in the measurement time of millisecond. With volume heating using near-infrared wavelength as a heating source, it was confirmed that nano-scale capillary wave can be induced within temperature rise of mK order. Then, we measured viscosities of liquid food sample (mixed milk and lemon juice) for cottage cheese manufacturing process, which is not required fermentation and ripening process. This result showed that we successfully detected viscosity change varied minute to minute due to the liquid separation (cheese and whey).

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Thermal conductivity is a crucial value in designing devices, and materials with high thermal conductivity are favorable for wide variety of applications. However, some of those materials are so small that conventional methods fail to measure thermal conductivity precisely. Here, we introduce a new technique for thermal diffusivity measurement, which observes the thermal resonance and is valid for a small specimen such as synthesized diamond. We describe the theory and the experimental method for this technique and present experimental results for small rectangular parallelepiped specimens. The results show quantitative agreement with reported values.

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