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Total emissivity of glass sheets varies with sheet thickness since glass is a semitransparent material. The total hemispherical emissivity, e h , of fused-silica and soda-lime glass sheets of different thicknesses was measured by a transient calorimetric technique previously proposed. The measured e h values are arranged together with those of borosilicate glass sheets reported in our previous work. The e h values obtained for various sheets are expressed as functions of sheet thickness and temperature. Further, the e h values are compared with other published data obtained by experiments and theory, and discussed. An edge effect caused by the temperature distribution on the specimen surface, is clarified and the error involved in the e h values measured by the transient calorimetric technique, is estimated. In addition, another edge effect caused by the distribution on the local total hemispherical emissivity on the specimen surface is made clear.

A method for measuring the effective thermal conductivity, λ e , of free-falling silica sand bed is described. The sand, made artificially from quartzite, was allowed to fall into cylindrical vessels 110 mm in diameter and120 mm high. Commercial grain size number of the sand ranged from 2 to 8 (corresponding peak diameters of the sand grains were 1680 to 74 μm). Bulk density of the sand, ρ B , was 1180-1460 kg m - 3 , and its porosity, Φ, was 45%-55%. λ e was measured at the temperatures of 25, 45, 65, and 85°C, in that order, under dry conditions, by the transient heat probe method. The measured values were found to vary with grain size number, porosity, and temperature from 0.17 to 0.46 W m - 1 K - 1 . The experimental results were analysed to evaluate λ e of the sand bed in situ by means of a three-phase model previously presented.

Studies of thermophysical and mechanical properties of rocks at great depths have been conducted as part of research into the hydrology and geochemistry of groundwater, the migration of substances such as uranium, and drift excavation effects on surrounding rock mass by the Japan Nuclear Cycle Development Institute. Measurement results and evaluation are given of thermal conductivity, λ, of core specimens collected from three research wells, 1000 m in depth, dug in granitoid stratum around the Tono mine, Japan. Twenty specimens were collected from each well, taking account of depth interval and lithofacies. The λ value of the specimens was measured by the unsteady hot-wire comparative method in the temperature range 25 - 85 °C. Experimental results showed that the values of λ were 1.9-2.1 W m - 1 K - 1 for conglomeratic sandstone, 2.9-3.6 W m - 1 K - 1 for quartz porphyry, 2.1-3.6 W m - 1 K - 1 for sandstone and 1.9-3.8 W m - 1 K - 1 for granite. A weak reverse temperature dependence of the λ values was observed in the tested temperature range. The distribution of the values of λ versus well depth, Z, showed that the values of λ were influenced by microcracks in the specimens which might have been caused by the stress released during the digging process of the core. In-situ λ values were evaluated with the core data prescribed above and the three-phase geometric-mean model as the A values for the intact rocks eliminated porosity.

Thermal conductivity, k, of several heat-absorbed soda-lime-silicate glasses has been measured by a transient needle probe method in the temperature range from 303 to 1473 K in order to obtain fundamental data for the float glass production process. Five cylindrical samples 100 mm in diameter and about 120 mm in height are used for the measurement. Samples used are ordinary clear float glass (CFL), bronze (BFL), gray (GFL), blue (HFL), and green (MFL) glasses. The physical properties of these samples are as follows: spectral transmittance (visible, 5 mm thickness) 89.3%, 63.9%, 64.3%, 77.5%, and 77.0%, respectively. The k values of these samples are measured at a set of temperatures: 303, 573, 773, 973, 1073, 1173, 1273, 1373, and 1473 K, by a transient probe method previously developed. The measured k values increase with rise of temperature in the range from room temperature to 1473 K. The effect of thermal radiation on the k values is discussed. It appears that the thermal conductivity is essentially unaffected by the addition of heat-absorbing components.

Thermal conductivity of several soda-lime-silicate glasses, which are called float glasses, has been measured by a needle probe method in the temperature ranges from room temperature to 1173K. Kinds of the samples were the ordinary clear float glass (CFL), bronze (BFL), gray (GFL), blue (HFL) and green (MFL) Masses. Experimental results showed that the thermal conductivity of the glasses increased gradually with rise of temperature in the ranges from room temperature to 1173K. Thermal conductivity values of the glasses measured do not depend on the kinds of samples, and it is considered that the measured values are real thermal conductivity. The values of conductivity of the glasses measured were about 1.0W/(m·K) at 303K, 1.3W/(m·K) at 773K, 1.4W/(m·K) at 973K and 1.7W/(m·K) at 1173K.

A new three phase equation to explain the effective thermal conductivity of moist rocks has been derived by analyzing data obtained with eighteen kinds of porous rocks at various moisture conditions. The equation is mathematically based on the weighed geometric mean, and it is modified to take into account the effect of porosity.In the equation derived, the effective thermal conductivity of the porous rocks is expressed as a function of the thermal conductivities of solid, liquid and gas and their volume fractions in the rock. Validity of the equation and degree of the influence of the affecting factors to the effective thermal conductivity of the three phased material have been also discussed.The equation correlates the experimental data within ±22% in accuracy. When the effective thermal conductivity, porosity and water content of a certain rock at only one condition are known, the effective thermal conductivity of the rock at other various moisture conditions may be estimated using the equation.

A simple method for measuring the thermal conductivity of low-conductive sheet materials such as a sheet of paper has been developed. A 7059 glass plate of 0.7 mm thickness made of CORNING is used as a reference material. An aluminum hot-wire of 10 mm length having rectangular crosssection of 0.5μm in thickness and 10μm in width is formed on the plate by sputtering and the photolithography technique. Seven kinds of thermal transfer paper for word processors are used as samples. A piece of the paper sample covered with a piece of impermeable polyimide tape that prevents moisture movement is put on the wire, another 7059 glass is placed on the paper sample, and a constant weight is loaded on the glass. The measured thermal conductivities of paper samples were from 0.3 to 0.41 W/(m·K). The data acquisition times are about 1.0 s. Errors in the present measurements are checked by the reference material.

私共の周囲には, 固体・液体・気体の三相から構成されている物体が極めて多い. 著者らは, 最近, 種々の湿った多孔質岩石の有効熱伝導率を測定し, その結果を固相, 液相及び気相の体積割合で整理する式を提案した. その折に, 他の分野での三相系物体に対しては, 既にどのような整理式あるいは理論模型が提案されているのかを知りたいため, 各分野の三相系物体の熱物性に関する研究例を調べた. 本稿では, 三相系物体の有効熱伝導率の基礎的模型, 各分野における三相系物体の有効熱伝導率研究の現状及び著者らの研究の概要について述べる.

The utilization of the energy of a supersonic water jet outflowing from a small-diameter hole under high pressure makes a progressive advance in material cutting. The history of the high pressure water jet technology applied to many fields as well as mechanical engineering has been surveyed briefly, and recent investigations and progress in the technology have been reviewed by classifying the technology into nine jets under cutting mechanism.

An experimental apparatus based on the transient hot wire comparison method was built for measuring the thermal conductivity of both water-saturated and-unsaturated rocks. A new method was developed for determining the time range necessary for calculation of the thermal conductivity in order to measure it accurately. The range is determined by using the second derivative of the hot wire temperature with respect to logarithm of time.The thermal conductivity of water-saturated rocks was measured in a water bath as well as in an airconditioned room. The measurements of the thermal conductivity of water-unsaturated rocks were also made in the same room. The thermal conductivity is able to be measured both in the water bath and in the room within ±5% accuracy in a wide range of 0.05 to 15W/(m·K). For measuring the thermal conductivity of water-saturated rocks, the steady state condition required as initial condition can be easily obtained in a water bath.

A new continuous measurement system has been developed in this study to measure the effective thermal conductivity, λe, of smelting granulated slag-water mixture beds and slag-cement composite materials under dry and wet conditions over the range from room temperature to 220°C. The measurement technique is based on a modified hot wire method. For the slag sample, lead smelting granulated slag, called “Black Sand” in Uguisuzawa, Miyagi Prefecture, was used. For the composite material, three samples, A, B and C that the values of a ratio of cement to Black Sand (C/BS) were different from each other were used. The C/BS values of the samples, A, B and C are 30/70, 25/75 and 20/80 by weight, respectively. The tested temperatures, θ, of the samples were set by considering utilization of the slag for the high level radioactive waste repository as buffer materials.The measurements of λe were conducted during both heating and cooling processes of the samples to evaluate a thermal hysteresis of λe. For the dry samples, the thermal hysteresis was not observed. The following equations of λe [W/(m.K)] of the dry samples were obtained:(1)λe=-0.000201θ+0.901 for Sample A, (2)λe=0.0004660+0.805 for Sample B and (3) Ae=0.0006820+0.798 for Sample C. On the other hand, for the wet samples, the thermal hysteresis was recognized. The λe values in the heating process were 0.9-1.5W/(m.K), but the values in the cooling process were 0.8-1.1W/(m.k). Thermal conductivity of solid component of the Black Sand, λs, was estimated from the λe of the Black Sand -water mixture beds and a thermal conductance model developed by the authors, and expressed as λs=0.0121θ+1.21. These results mean that Black Sand may be an effective buffer material having sufficiently good heat conducting properties to keep the temperature of deeply buried canisters within a suitable interval.

An experiment was carried out to find out the influence of long standoff distance, X, and target material temperature, θ, on water jet penetration depth, Q, by striking room temperature water jet with a velocity of about 126m/s at the nozzle exit (diameter, Do=0. 7mm) against a refractry material during10s in both ranges of θ from17°C to1000°C and of X/Do from 20 to 800. The experimental results indicated that the Q generally became maximum at θ between 400°C and 800°C at the specified X/Do, and became maximum at X/Do between 100 and 400 at the specified θ.

Heat conduction in the cuttings-water mixture beds has been analyzed using Kunii's formula. The analysis was conducted to estimate thermal conductivities of formation rocks in situ from the effective thermal conductivity of the cuttings beds which were measured at simulated geothermal conditions by a new rapid measurement method developed by the authors. As the results of numerical experiments by the analysis, it was made clear that controlling parameters for the thermal conductivity of rock martix of the cuttings estimated, λs, were the total porosity and the effective thermal conductivity of the mixture bed measured.All measurements of the effective thermal conductivity, λe, of the mixture beds of water and cuttings from SKG-11D well, Fushime geothermal field, Kagoshima pref., Japan were conducted at the natural cooling process from 200°C to room temperature as the results of the preliminary study by using fused quartz grains. The estimated values of thermal conductivity of dry cutting particles saturated with dry air, λea, of the samples from the well agreed well with the measured values of λea of the core samples from the corresponding strata within the experimental errors. The effective thermal conductivity of rocks in situ of the well at the depth from 1, 500 to 1, 900m was estimated at 3 to 4W/(m•K).

The transient hot-wire method have been used to measure the thermal conductivity of gases and liquids acculately using a very thin wire of diameter from 15 to 40μm, recently. On the other hand a practical method to measure thermal conductivities of viscous suspensions contained fine and/or coarse grains easily with practically enough accuracies at a high temperature and high pressure is needed in the fields of drilling technology and others. A needle probe type sensor having 2mm in diameter and 1, 000mm in length with a thermopile of six magnifications of sensitivity of temperature and the measuring system were developed. The thermal conductivites of three standard and test samples were measured by analyzing the data of smooth curve relations at an early period between the temperature increase of the probe and the constant heat supplied time to the probe using a theory of unsteady hot thick wire method and the multivariate analysis. Measurement errors of this method were estimated at less than ±10%. Thermal conductivity of montmorillonite-water based muds having concentrations of 3.0, 6.0 and 10.0% were measured at the temperature range from 20 to 180°C. From the measurement characteristic temperature and concentration dependencies on the thermal conductivity of the mud were obtained.

Because of the high interfacial tension between water and oil, the injection pressure of water in water flooding is fairly high and the subsequent oil displacement efficiency is rather low. Then the improvement was aimed for the reduction of injection pressure and the efficient displacement by adding a small amount of surfactant into the injection water. Surfactants used were Polyoxyethylenenonylphenylether HLB=17.1 and 12.6 as nonionic, and SDBS as anionic. These were separately used as water solutions of 300ppm in concentration without any additives like alcohols as co-surfactants.Results are summarized as follows.(1) Adding a surfactant into the injection water can reduce the injection pressure surprisingly even if the concentration of the surfactant is as low as 300ppm, which is 1/50 to 1/100 of that in the low concentration surfactant flooding. Results were correlated with the capillary number as shown in Fig. 10.(2) 300ppm surfactant-water solution was able to increase the oil recovery. This may be caused by the snap-off mechanism proposed by ARRIOLA et al.(3) krw/kro decreases with decreasing the interfacial tension, that is to say, the oil gets to flow easily compared to the water as the interfacial tension decreases. This effect was related to the shift of residual oil saturation with the interfacial tension.

Four dimensionless parameters, l/D0, (Ts-Tw)/Tw, (Pt2+Pw2)0.5/σ and aw/as which are related to drilling depth, rock and mud jet temperatures, forces loaded to the rock and the rock strengths, and the rock and the mud thermal properties, respectively, are adopted in this study. The parameters were obtained from dimensional analysis. Also, a few model experiment were carried out using a relatively low velocity pure water jet and imitation hot dry rock specimens made of castable fireresistant material. The jet velocity used was 98m/s at nozzle exit and the nozzle diameter, D0, equals 1.4mm. Temperature of the specimens tested were about 15, 200, 400, 600, 800, 1, 000 and 1, 140°. Dimensionless standoff distance was kept constant at 28.6. Jet operation time was fixed at 10s. A correlation equation between l/D0 and the other parameters described above was developed from the multivariate analysis and the experimental data:l/D0=4541(Ts-Tw/Tw)-0.3914(√Pt2+Pw2/σ)-0.9750(aw/as)4.414

Experiments for fracturing hot dry rock by high speed water jet were carried out. In this study the effects of rock temperature and water jet speed were studied. Specimens were 75mm in diameter and 150mm in length and were made of castable fire-resistant material. Their minimum compressive and tensile strengths were shown in Table 1. Temperatures of the specimen tested were 15, 200, 400, 600, 800, 1, 000 and 1, 140°C. Water jet speeds used were 70, 84 and 98m/s at the nozzle exit. The nozzle diameter, Do=1.4mm I.D.. The distance between the nozzle exit and the test surface of the specimen was kept constant at 40mm. Jet operation time was fixed at 10s.The experimental results indicated that the fracturing pattern and effectiveness varied characteristically with the specimen temperature and the jet speed.