This paper described heating properties of an agar phantom with cooling effect of blood perfusion. In the agar phantom, two separated blood vessels were placed. The purpose of this study is to demonstrate the cooling effect for tissue temperatures around blood vessels. We calculated temperature distributions for the phantom model with a resonant cavity by FEM. From these results, it was found that cooling effect of blood perfusion appears in the region from blood vessel approximately 1-2 cm.

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This paper describes a new heating control method of a resonant cavity applicator with a dielectric bolus for a 3-D anatomical human head model. We have already proposed the resonant cavity applicator for deep seated brain tumors hyperthermia treatments. In this paper, first, the method using dielectric bolus was described. Second, the 3-D anatomical human head model which was reconstructed from 2-D MRI and X-ray CT images was presented. Finally, from the result of temperature distributions with blood flow rate, it was found that the proposed method was useful for effective hyperthermia treatment.

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Recently, information and communications technologies (ICT) have been widely used in the air-conditioning field, and high- performance and density ICT facilities have been rapidly growing. At the same time, the heat generated per unit area of conventional data center in an ICT facility is an extremely serious problem. Therefore, this study aims to investigate the performance and characteristics of the server spot cooling heat transportation system adopting CO_2 as the working fluid to prevent the occurrence of hot spots and decrease the power consumed by a conventional overall air conditioning system installed at a data center with experiments and simulations.

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The daily performance of a CO_2 heat pump water heating system with a hot water storage tank is affected by the history of daily hot water demand and heat pump operating conditions. It is important to estimate the values of daily performance criteria accurately under daily changes in hot water demand and operating conditions for optimal operation. In previous papers, a neural network model has been proposed for this estimation, and it has turned out that the estimated values of daily performance criteria have high accuracy. In this paper, this model is applied to determination of operating conditions to attain the optimal system performance under certain hot water demand. The validity and effectiveness of this approach are ascertained by a numerical study using a simulated hot water demand.

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For the development of high performance and small sized carbon dioxide (CO_2) heat pump water heater, high performance heat transfer tube is very important. In the previous studies, parts of the authors experimentally clarified average boiling heat transfer coefficient of CO_2 in horizontally located smooth tubes takes a maximum against mass velocity but not in grooved tubes. In this study, the experimental data are compared with conventional correlations based on local coefficients to clarify the phenomena, and also predicting performance of the correlations is examined. It is concluded that more experimental data in dryout and post-dryout region should be obtained.

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The gas-liquid flow distribution in a multi-pass channel with horizontal headers and downward branches was examined experimentally. At first, the refrigerant two-phase flow in the channel was visualized to make clear the flow characteristics in the dividing and combining headers. Then, the air-water flow was observed and the air and water distribution ratios in the branches were measured under following four air and water velocity conditions at the header entrance: (a) equal superficial velocities, (b) equal kinetic energies, (c) equal quality and mass flow rate and (d) equal Baker flow pattern map parameters. The results obtained in the air-water flows were closely compared with those observed in the refrigerant flow. It was found that the condition of equal superficial velocities was most suitable for simulating the refrigerant two-phase flow.

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Performance test of CO_2 heat pump was carried out experimentally. Effects of refrigeration oil on the performance were especially investigated. The experiments were conducted under the different oil circulation ratio from 0 to 1.5 mass%. Flow configurations of the oil were observed. Flow of oil droplets and oil film on the wall started to be observed from the oil circulation ratio of 0.1mass%. The oil film was formed on the entire wall and its thickness increased with the increase of mass flux. The COP was decreased with increase of the oil circulation ratio and the decrease is saturated from the oil circulation ratio of 0.5mass%.

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In the case that a plate heat exchanger is used as an evaporator, the heat transfer performance may strongly depend on the flow behavior of gas-liquid two-phase flow. The FC-72 boiling heat transfer characteristics with hot water heating were examined for a single-channel plate fin heat exchanger with an offset fin. Heat transfer rate increased with increasing the flow rate of hot water, however the amplitude seemed to be saturate in high flow rate condition of hot water in spite of the decrease in the effectiveness in the heat exchange. The reason might be on the heat transfer deterioration in the refrigerant flow due to the flow pattern of boiling two-phase flow.

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Numerical calculations for the cavity flow which simulates Joule-heated glass furnace were executed using finite element analysis (FEA) code. The cavity consists of two electrode plates on facing sides and constant temperature wall on the top working as a heat sink. Relative magnetic permeability (μ_r) of molten glass to air was widely varied from 1 to 10. In case μ_r = 1, magnetic permeability is small, unsteady downflows occurred from top surface of the cavity. However, in case μ_r = 10, magnetic permeability is large, a large and steady upflow appeared in the center of cavity. Magnetic permeability largely affected flow characteristics of the cavity, and it may be able to contribute to stable operation of the glass furnace.

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Experimental investigations have been carried out on opposing mixed convection of water around a heated vertical plate. The length of the plate is 50 mm. The plate is heated with a constant heat flux. The experiments cover the ranges of Reynolds and modified Rayleigh numbers as; 4×10^2<Re_L<2×10^3, 4×10^7<Ra_L^*<3×10^9.The flow fields around the plate were visualized with dye. The result shows that a separation of the boundary layer flow appears first at the trailing edge of the plate when the non-dimensional parameter (Gr_L^*/Re_L^<2.5>)=0.4 and the separation point reaches to the leading edge when (Gr_L^*/Re_<L<2.5>)=3. Moreover, the local heat transfer coefficients of the plates were measured. The results show that the heat transfer is not coincided with that of the pure forced convection by the above flow separation.

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Experimental investigations have been carried out on combined convective flows over upward-facing, circular heated disks placed in a vertical downward flow of forced convection. The experiments were performed with air in the ranges of the Reynolds and Grashof numbers as; 100<Re_D<2x10^4, 10^4 <Gr_D<10^7. The flow fields over disks are first visualized with smoke. The results showed that a twin-vortex appears over the disk intermittently when the buoyancy force is beyond critical, and that the onset of the above twin-vortex can be predicted with the Richardson numbers as; Gr_D/Re_D^2 =3.1. The overall heat transfer coefficients from the disks were subsequently measured. The results showed that the coefficients are increased significantly from those of the laminar stagnation point flows with the occurrence of the twin-vortex.

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Growth rate of TiN film by thermal CVD has been investigated. When the setting temperature, Ts, is 1000℃, the growth rate increases rapidly in the beginning, and it decreases exponentially with the distance afterwards. In this case, the growth rate is controlled by the diffusion of TiCl_4 on the wall. The controlling step doesn't depend on the flow rate of gas. On the other hand, at Ts=800℃, the unreacted gas increases because the rate of surface reaction decreases. The growth rate depends on the temperature distribution. Therefore, growth rate of TiN film changes into diffusion controlled reaction and the surface reaction on the condition.

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2D computer simulation assists in the decision of growth parameters to reduce the crystal defects of GaAs crystal in liquid encapsulated Czochralski (LEC) method. In this paper, we numerically investigated the reason why the 450mm-long crystal has more crystal defects than the 350mm-long crystal by comparing heat exchange, temperature distribution and velocity vector in the source melt at several stage of the growth. The simulation results indicated that large heat release from crystal and small heat release from crucible bottom are advantageous to the crystal growth with few defects. It is also necessary that forced convection and natural convection of GaAs melt is delicately controlled by the crucible rotation rate and the temperature distribution.

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The guarded hot plate (GHP) method is the most popular way of measuring thermal conductivity of thermal insulations. However, there are large differences among the thermal conductivities measured by different GHP apparatuses which are made in different institutions in the temperature range above 100 ℃. It must be the reason why GHP apparatuses have complex structures for realizing the principle of the GHP method. In this study, the new estimation method for thermal conductivity was proposed, when using the GHP method. This method makes use of heat losses from side surfaces of the specimen. It was assumed that the heat generated in the metering section heater separates into two heats in the directions of thickness and plane of the specimen. Then, the relationship between the measured thermal conductivity λ and the estimated one λ_t in the direction of thickness was derived. By using this relationship, the thermal conductivityλ_t, in the direction of thickness was determined.

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It is important to establish permanent technologies for the cryopreservation of foods and organs. For this purpose, the present authors have focused on winter flounder antifreeze protein as an additive. We have measured temperature field and heat flux near the interface during unidirectional freezing of the aqueous solution of antifreeze protein in a narrow space. We have applied the detection of near-infrared light using a camera to the measurement. In this report, we verify that the near-infrared light of 1921nm is appropriate for the measurement. We also discuss the heat fluxes near the interfaces of ice/water and ice/solution.

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A volumetric velocity measurement system has been developed by using Stereo Streak PTV (Particle Tracking Velocimetry) with shadow image and applied to complicated flow fields. After recording particle shadow images from two directions, 2-component velocity-vectors were obtained by Stereo Streak PTV and 3-component velocity-vectors were reconstructed by the stereo view. This measurement system was applied to the aneurysm model including 3-dimensional vortexes. It can be seen that each tracer particle was 3-dimensionally traced with time-series. The measuring area was nearly 10^3 mm. This proposed method is the effective procedure to measure accurate 3-dimensional and 3-component velocity-vectors.

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We have focused on winter flounder antifreeze protein as a useful agent to establish technologies for the cryopreservation of foods and organs. The purpose of this study is to clarify the freezing characteristics of flowing aqueous solution of antifreeze protein. We have measured near-infrared light using a camera and obtain temperature field near the ice/water interface during unidirectional freezing of water flowing in a mini-channel. We found a problem for our calibration. Moreover, we carry out visualization of flow field of freezing aqueous solution of antifreeze protein near the interface. The high velocity occurs due to the narrower cross section due to the freezing.

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The spark tracing which is measurement method that doesn't need particle tracer was used to obtain the time line images of gas mixing process in sub-milli-scale. The parameter changed in this research was the flow rate (Re = 65, 135) and temperature of gas (298, 318, 343[K]). This measurement can change the resolution time by changing the interval time of the added pulse voltage, and we archived it to 0.1ms. Firstly, the relationship of spark width and the velocity was searched for, and velocity was calibrated, we succeeded in measuring velocity by spark tracing. From visualization picture, it was shown clearly that flow velocity becomes high near channel exit and by high Reynolds number. Moreover, this measurement was possible to measure flow velocity without calibration even if the temperature of operation fluid changed.

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Temperature distribution of the methane flame was measured by using the high-speed laser speckle method. The burner used a treble circular tube. The flow rate of methane is 0.5 l/min in the first nozzle, and the flow rate of air is 5.0 l/min in the second nozzle, the flame was oscillating. There is an oscillatory phenomenon in the flame that is called a flickering. But it did not oscillating when the flow of nitrogen is 7 l/min in the 3rd nozzle. Furthermore, from Fermat's principle and Gladstone-Dale's equation, the temperature distribution of the unsteady and oscillatory diffusion flame has been predicted.

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We have proposed a novel measurement technique of a time-series 3-D temperature distribution in turbulent flames by using heat radiation from a Hi-Nicalon fiber array. First, we demonstrated measurements of instantaneous 2-D flame temperature distribution by this technique. Then the second step, in this paper, measurement of Time-Series 1-D temperature distribution of turbulent flames is carried out toward completing the time-series multi-dimensional measurement. In addition, we tried to improve the time-response of the system by utilizing the property of the fine wire having first-order time-lag. In compensation procedure for a first-order-time-lag, we used the curve fitting procedure for first-order-time-lag and Fast Fourier Transform/Inverse FFT. As a result, temperature histories with compensation show steeper fluctuation than original one, resulting in an improved time response.

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Characteristics of combustion and radiation of a gas burner were examined in order to shift the fuel from a heavy oil and coal to a natural gas with the lowest C/H ratio and to reduce CO_2 emission from the burner of industrial furnaces and electric power plants. The energy flux radiated from the flame indicates a high value in the area of the high temperature and the high concentration of CO_2, CO. A high radiation intensity appears in the radiative wavelength bands of CO_2, CO and H_2O. It means that characteristics of radiation from the gas flame can be controlled by changing characteristics of combustion in the gas burner.

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This paper describes the radiation effect on the NOx emission of confined nonpremixed flames. The characteristics of confined flames are strongly affected by the entrainment of burned gases. The burned gases have two factors; one is dilution and the other is heating. Proper combination between geometries of burner and furnace can reduce the NOx emission. The radiation effect on the NOx reduction has been investigated by comparing NOx emissions from two furnaces with Pyrex glass and stainless furnace walls. It was found that the radiation fraction has a logarithmic relation to the product of global equivalence ratio and flame volume.

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Computational and experimental investigations of radiative counterflow premixed flame at extremely small stretch rate were conducted to clarify the behavior at lower flammability limit. Stretch and radiative extinctions of both Xe-diluted and Kr-diluted counterflow flames were obtained. Flammable region of Xe-diluted counterflow flame was broader than that of Kr-diluted counterflow flame. Lower flammability limit of counterflow planar flame was smaller than that of flame ball using Xe-diluted mixture and larger than that of flame ball using Kr-diluted mixture. These differences of extinction characteristics are due to the lower-Lewis-number of Xe-diluted mixture. Transition from planar flames to a ball-like flame was observed in microgravity experiment and ball-like flame seems to have correlation with flame ball.

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Pure oxygen combustion has been attempted with using a rapidly-mixed type tubular flame burner. Instead of nitrogen in the previous study, carbon dioxide was used as a diluent and combustion characteristics were investigated as functions the oxygen concentration in the oxygen/carbon dioxide mixtures. Results show that stable combustion can be obtained in wider equivalence-ratio range for carbon dioxide than for nitrogen. Less burning velocities in carbon dioxide mixtures than in nitrogen mixtures seem to be attributed for their wider stable combustion range. Burning velocity control is important to get stable pure oxygen combustion.

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Effects of inert gases on the vortex bursting in a small-diameter tube have been experimentally investigated. Methane was used as fuel. Results show that the flame propagation has observed for carbon dioxide mixture at 30% oxygen concentration within a 3.6mm tube which is less than the quenching diameter (5.9mm). Such flame propagation may attribute to the large pressure difference between the unburned and the burned gas. Furthermore, for carbon dioxide mixture, Lewis number is significantly lower than unity, hence, combustion was intensified at the flame tip which promote the flame propagation within the tube less than quenching diameter.

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Effects of inert gases on the vortex bursting in a small-diameter tube have been experimentally investigated using nitrogen, and carbon dioxide as inert gas. Methane was used as fuel. Results show that the flame speed V_f of carbon dioxide flame takes its maximum at Φ=0.7 where the flame diameter D_f is minimum. Detailed flame observations have revealed that, just after the ignition, the flame near the burner exit was extinguished by the strong wall effect, and the slender small flame propagates rapidly along the vortex axis without an approach to the wall.

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Vortex bursting has been investigated by many researchers for analyzing the turbulent flame structure and developing the new combustion system in recent years. But few research for vortex bursting in the high-pressure such as turbulent flames in internal-combustion engine is investigated. In this report, flame visualization of spark ignited premixed flame in a rotational cylindrical closed cuvette is made for initial pressure condition of 1〜5atm, and rotation condition of 0, 4800, 9000, 15000rpm. The initial pressure conditions are set to be as same as that of micro gas-turbine combustion.

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The effects of blockage ratios (BR) of the Shchelkin spiral on characteristics of deflagration-to-detonation transition (DDT) in a vortex flow were examined in order to control the DDT distance without losing the simplicity inherent pulse detonation engines. The DDT distance decreases with increasing the BR of the Shchelkin spiral. However, the optimum value of BR exists. The DDT distance is deteriorated if the BR exceeds the optimum value. Optimizing the BR of the Shchelkin spiral is another way to shorten DDT distance in a vortex flow.

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Unsteady two-dimensional numerical study has been done for the forced convection around the porous rectangular cylinder which has heat generation. If aspect ratio of the porous rectangular cylinder is relatively small, flow entering from the front of the cylinder flows out from the rear of the cylinder and suppresses the generation of the Karman vortices, reduces the pressure drop behind the cylinder. Here the drag coefficient is smaller than that of impermeable solid cylinder. When aspect ratio is relatively large, the permeating flow drains from the side before it reaches the rear and the pressure drop of the wake is not suppressed. Here the drag coefficient may be larger than that of solid cylinder because the internal friction becomes dominant. Heat transfer characteristic around the porous cylinder is strongly affected by the permeating flow.

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The recent development of information technologies due to advent of a new generation of semiconductor devices has brought us serious problems associated with high heat generation density. Conventional cooling methods such as fin heat sinks with blowing fans may not be sufficient to solve such serious heat related problems. Thus, in this study, we propose a new kind of heat sink as a solution to the problems, namely, a pin fin heat sink filled with metal foams. A series of exhaustive experiments have been conducted to confirm heat transfer enhancement as results of extended surface area and fluid mixing due to the presence of metal foams. Theoretical consideration has also been made so as to elucidate such heat transfer enhancement mechanism.

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The present paper deals with simulation of microstructure and macroscopic thermal conductivity of randomly packed, uniaxially pressed and sintered particles. Random packings of identical spheres are constructed by using a sequential deposition method and their microgeometry after the compaction in sintering is geometrically created by proportional reduction in distances between the sphere centers only in the vertical direction and by mass addition around overlapped necks. Using the data on the packings and geometrical models, macroscopic thermal conductivities of the compacts are estimated. It is found that the conductivities are greatly different from those of simple cubic packings, although both the packings have almost the same coordination number, and that anisotropy in the conductivity is induced by the compaction in addition to gravity. The conductivities are expressed as a function of the compaction and sintering degrees for practical purposes.

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This paper describes how to visualize the flow structure in a porous medium by matched refractive index PIV method. First of all, the flow structure in a sphere-packed pipe is introduced for confirming the validity of the matched refractive index method, and then, the applicability of this method toward micro channel flow of porous media are discussed for both a single-phase flow and a two-phase flow.

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The problem of removal of high heat flux in unsaturated packed beds due to supplying water is of concern in variety of engineering applications such as fire fighting problem and post-accident boiling of fluids within nuclear reactor debris. In this paper, the characteristic of heat transport in unsaturated packed beds including vaporization of supplying water has been investigated experimentally. It was found that the cooling process of packed bed due to supplying water droplet strongly depend on the mass flux and temperature of supplying water droplets, and, pressure of vapor phase in packed bed.

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The effect of the stability of a displacing front in gravity drainage on the displacement efficiency was discussed with dimensionless parameters. For gravity drainage in stable conditions, high displacement efficiency is achieved without the effect of gas fingering with the aid of a stable interface of displacement. When the displacement velocity is above the critical gravity drainage velocity, large fractions of water remain in the packed bed. Reflecting the nature of instability, the initial gas saturation varies widely from drainage to drainage. Heterogeneity in porosity enhances the effect of fingering and reduces the displacement efficiency. With an increase in Bond number and a decrease in capillary number, the initial gas saturation increases.

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CO_2 geological sequestration is considered as one of the effective technology to mitigate global warming by reducing carbon dioxide (CO_2) emission into the atmosphere. However, density difference between CO_2 and water causes buoyancy effect and CO_2 migrates slowly upward in the aquifer. In order to clarify the fundamental mechanism of CO_2 migration, microscopic study of immiscible two-phase flow of CO_2 and water in porous media is necessary. In this study, Lattice Boltzmann method (LBM) for supercritical-CO_2/water two-phase flow in a porous media has been performed under geological storage condition. Migration process of CO_2 droplet was visualized and analyzed in micro pore scale.

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In the previous paper, we had proposed a new model for frost heaving considering the swelling in soil. In this paper, we have investigated the effect of NaCl solution on frost heaving for swelling soil experimentally. Using bentonite particles in NaCl solution, the swelling pressures in equilibrium decrease with the increase in the concentration of NaCl solution because of decreasing the osmotic pressure difference between NaCl solution and Na^+ ion existing on bentonite particles. Under the constant freezing rate, the frost heaving pressure strongly depends on the concentration of NaCl solution and a higher concentration in NaCl solution leads to a lower heaving pressure due to freezing.

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This paper presents an investigation on the thermal characteristics in a layer of an exothermic powder mixture that is utilized in body warmers, hot compresses and so on. The research objective is to develop a manufacturing process that enables the exothermic temperature to be controlled in order to prevent cases of low-temperature bums. Absorbent polymer powder including saline solution is added into the exothermic powder mixture, and its effects on the reaction velocity and the thermal characteristics are examined experimentally.

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We investigated the effects of concentration in solution, humidity and difference in temperature between substrate and humid air on pore size. We fabricated porous polymer thin films by using the breath figure method. As the experimental results, a porous polymer thin film with small pores was fabricated in a low humid condition and in condition with small temperature difference between substrate and humid air. A porous polymer thin film with 100-150 nm pores was fabricated by controlling growth time of water droplet.

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Irreversible electroporation (IRE) is a technique to perforate a cell membrane by electric pulses and induce necrotic cell death around electrodes. It is attracting much attention because of its high potential to be used as a less-invasive treatment for tumor. Successful IRE needs to apply a pulsed voltage not only beyond a threshold to the cells but also that minimizes the Joule heating effect. The aim of this study was therefore to establish a new method to experimentally determine the temperature distribution during the IRE. Temperature-sensitive ink was used to visualize the in-situ temperature rise. Chromatic change of the ink depending on the temperature was preliminarily calibrated by a transient short-hot-wire technique combined with color analysis of the ink, and then utilized to determine the temperature distribution resulted from the electric pulses applied to the electrodes in a simulated tissue.

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In this present study, by employing an actual UV-imprint system we measured the fluid motion during a press process and during a UV photo-curing that follows the press process. Thus, we report on a technology of detecting the 3-D position of a particle during the press process and during the photo-curing that follows the press process. The displacement is obtained by the detection of the particle position and is carried out by a digital hologram technique.

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In automobile exhaust systems, catalytic converters have become essential in reducing environmental pollutions and contaminations. The goal of our research is to simultaneously reduce the pressure loss and improve the flow distribution under spatial constraints. In our past studies, the possibilities of two types of flow deflectors with shell structures, were investigated. These deflectors can reduce the pressure loss and improve the flow distribution in steady flow and pulsation flow. However, in these studies, we have not revealed the effect of fluctuation component of pulsating flow. So, in this study, we find out flow distribution and wave forms at each instantaneous time of pulsating flow by visualization of the flow passing through the monolith and using PIV technique at the behind of catalytic monolith.

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The objective of this investigation is optimization for manufacturing laser welding process of crystalline polymer with experimental and numerical studies. Experimental results showed that the precise control of laser power was important for obtaining high quality welding products. It was found by Monte Carlo simulation that the difficulty of the numerical estimation of laser input power was caused by the precise estimation of laser efficiency because of energy loss due to permeation and refraction. The numerical result on convective phenomena in a molten pool indicated that the convective heat transfer was important only near the free surface, and the molten zone was very thin. In order to overcome these difficulties in the welding process, we proposed a newly defined absorption energy parameter. By rearranging the experimental results using this parameter, the laser efficiency on crystal polymer welding can easily be estimated.

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Recently, ice trapping ozone gas having the effects of sterilization and deodorization is noticed for a cold storage of foods. In order to trap ozone gas in ice efficiently, authors have proposed use of micro-bubbles with bubble size of several tens micro-meters. Since ice including ozone micro-bubbles has double effects of ozone gas as ozone bubbles and ozone dissolving in water, each ozone can be used effectively during melting of the ice. In this paper, as the first step, oxygen gas was used because of easy handling. And suppression effect of lifting speed of oxygen micro-bubbles due to addition of a small amount of surfactant was investigated. And influences of the suppression on trapping rate of bubbles and bubble size trapped in ice were clarified.

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This paper focuses on temperature rise due to the viscous heating in liquids flowing through micro-channels. A correlation for the temperature rise has been obtained as a function of the friction factor, Reynolds number and Eckert number, starting from Navier-Stokes equations and energy equation under the assumption of fully developed flow. The temperature rise calculated from the correlation has been compared with experimental data and the correlation is validated. However, in this paper, a new correlation for the temperature rise is simply obtained from the first law of thermodynamics without limitation of fully developed flow.

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Experimental investigations on nitrogen gas flow characteristics were conducted for a micro-tube. The micro-tube was fabricated in a stainless steel block by electrical discharge machining (EDM). The micro-tube was designed with a main flow tube and five pressure ports, which were led to the pressure transducers. The average diameter and the length of the main tube were of 373 μm and of 40 mm, respectively. The outlet of the tube faced to the atmosphere. The pressure of turbulent gas flow through a micro-tube falls steeply and Mach number increases near the outlet with increasing the inlet pressure due to flow acceleration. It is found that there exists a threshold of Mach number at which the local values of friction factor for the turbulent flow regime abruptly increase. In additional experiments, the flow at the micro-tube outlet was visualized by using a Schlieren method.

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Adhesion of frost crystals to a cooling solid surface has caused many serious accidents accompanying economic losses. Thus, it is necessary to clarify the mechanism of frost crystal adhesion to the cooling solid surface both scientifically and technologically. Considering the size of frost crystals, it is essential to investigate frost crystals in nano-micro scale fields. Thus, authors have developed the methods for measuring frost crystal dimensions/structure and scraping force of forest crystals from the cooling solid surface by using a scanning probe microscope (SPM). And, the methods' validity and effectiveness have been clarified. In this paper, a new method to estimate distribution of frost crystals is also proposed, and the correlations among frost crystal dimensions/structure, distribution of frost crystals and scraping force of forest crystals were clarified.

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