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Showing papers in "Jsme International Journal Series B-fluids and Thermal Engineering in 1959"


Journal ArticleDOI
TL;DR: In this paper, the characteristics of spray penetration are discussed from the viewpoint of momentum theory based on the idea that the air induced into a fuel jet stream makes a kind of mixed gas together with fuel droplets.
Abstract: Regarding the penetrating distance of fuel spray in a diesel engine, the old theory dealing with the motion of a fuel droplet in still air is recognized not to coincide with the actual phenomenon in a diesel engine because of the extremely small size of atomized fuel droplets and the very high density of gas in cylinder. In this paper, the characteristics of spray penetration are discussed from the viewpoint of momentum theory based on the idea that the air induced into a fuel jet stream makes a kind of mixed gas together with fuel droplets. According to the results of experiment, the authors confirmed that the theory was satisfactory, that there existed the simple relations among several dimensionless numbers which indicate the effect of various factors on the spray penetration, that there is a close relationship between the spray cone angle and penetration, and others.

282 citations


Journal ArticleDOI
TL;DR: In this paper, the authors measured the heat transfer by convection in the annular gap between the rotating inner cylinder and the stationary outer cylinder and found that the rate of heat transfer increases with rotational speeds under the influence of secondory vortexes by the centrifugal force.
Abstract: The heat transfer by the convection in the annular gap between the rotating inner cylinder and the stationary outer cylinder was measured in the air, spindle oil and mobil oil at varying rotational speeds, cylinder diameters and widths of gap. The results show that characteristics of the flow and heat transfer have two modes. If the rotational speed is low and the width of gap is narrow, namely (vδ/ν)(δ/r)1/2 41, the rate of heat transfer increases with rotational speeds under the influence of secondory vortexes by the centrifugal force, which may be given by [numerical formula]Where U denates the overall coefficient of heat transfer through the gap, δ the width of the gap, λ the thermal conductivity, ν the kinematic viscosity and Pr the Prandtl Number, r and v are the radius and the peripheral velocity of the rotating cylinder respectively.

77 citations


Journal ArticleDOI
TL;DR: In this paper, the behavior of chip in steel cutting for the purpose of controlling the shape of chip is described, and the authors have drawn up nomographs for the flowing-out angle of chip on the basis of the theoretical equations.
Abstract: This paper describes the behavior of chip in steel cutting for the purpose of controlling the shape of chip and contains the following two parts. The first part describes the angle of flowing-out of chip and, since its values calculated by the theoretical equations are in accord with the measured values for various cutting conditions and tool designs, the authors have drawn up nomographs for the flowing-out angle of chip on the basis of the theoretical equations. The latter part describes the chip classification and the effect of cutting conditions on the shape of chip.

43 citations


Journal ArticleDOI
TL;DR: In this article, the fundamental equations of motion for pseudo-plastic and dilatant fluids were deduced, and it was proved that the equations of minimum dissipation of energy for these fluids are equivalent to the equation of motion, if inertia terms are neglected and external forces derived from a potential or zero.
Abstract: In this paper, we first deduce the fundamental equations of motion for pseudo-plastic and dilatant fluids. Secondly, it is proved that the equations of minimum dissipation of energy for these fluids are equivalent to the equations of motion, if inertia terms are neglected and external forces derived from a potential or zero. Then, the flow past sphere is approximately solved using this energy method.

43 citations


Journal ArticleDOI
TL;DR: In this paper, an experimental study was made on the dynamic theory of piston-ring lubrication, which was introduced in the 1st. report, and the experimental results gave a good agreement both qualitatively and quantitatively with the theoretical value.
Abstract: An experimental study was made on the dynamic theory of piston-ring lubrication, which was introduced in the 1st. report. The apparatus used in this investigation had a stationary piston and a moving cylinder, the speed of which could be accelerated to 2000 rpm, and a constant or varied load was applied to the piston-ring by means of a rubber tire, which was pushed out by the compressed fluid. When the speed, load, temperature, and the phase of the varied load being changed, a frictional force of the piston-ring is measured by an electronic device which consisted of an elastic diaphragm, movable anode tube and oscillograph. These experimental results gave a good agreement both qualitatively and quantitatively with the theoretical value.

32 citations


Journal ArticleDOI
TL;DR: In this paper, the free convection heat transfer from a vertical cylinder of about 360 mm in height and about 76 mm in diameter to ethyleneglycol or water has been studied experimentally.
Abstract: The free convection heat transfer from a vertical cylinder of about 360 mm in height and about 76 mm in diameter to ethyleneglycol or water has been studied experimentally. The local heat transfer coefficients, which are measured directly, are scarcely affected by the development of the vortex street in the boundary layer, but are discontinuously increased by the transition to a turbulent flow. The results for ethyleneglycol are as follows : GrPr < 8.5×109 : Nux=0.49 (GrxPr)1/4 8.5×109 < GrPr < 8×1010 : Nn=0.87 (GrPr)1/4 The temperature distributions in the boundary layer are also measured.

28 citations


Journal ArticleDOI
TL;DR: In this paper, the buckling problem of a rhomboidal plate with all edges clamped, on which compressive or shearing force is applied along its edges, is studied by using the energy method (Lagrangian multiplier method).
Abstract: Buckling problems of a rhomboidal plate with all edges clamped, on which compressive or shearing force is applied along its edges, are studied in this paper by using the energy method (Lagrangian multiplier method). Natural vibrations of the plate are also considered. The lowest buckling loads and the fundamental frequencies for several oblique angles are calculated. Convergency of the solutions is considered good enough.

26 citations


Journal ArticleDOI
TL;DR: In this article, the authors carried out experiments on a regenerative pump systematically, changing the dimensions of flow channels, impellers and clearances, and they proposed a "characteristic dimension of flow channel" for a parameter.
Abstract: The authors carried out the experiments on a regenerative pump systematically, changing the dimensions of flow channels, impellers and clearances. And they propose a "characteristic dimension of flow channel" for a parameter. Then the following results are obtained through above experiments. (1) The influence of the clearances on the pump performance depends on the characteristic dimension of flow channel. The allowable clearance is decided by the value of the characteristic dimension of flow channel. (2) The pump efficiency is high in the adequate range of impeller dimension and characteristic dimension of flow channel. (3) The influence of number of vanes on the pump performance depends on the width ratio of vane. (4) The pump performance depends on the combinations of characteristic dimension of flow channel, width ratio, thickness and length of vane. (5) The upper and lower limits of characteristic dimension of flow channel are fixed by the values of clearance and dimension of impeller.

16 citations


Journal ArticleDOI
TL;DR: In this paper, the cavitation aspects in the impellers are presented by photographs and their correlations with the various local pressure drops are discussed, with a view to applying them to the practical fields.
Abstract: Investigations concerning cavitation in several impellers with three dimensional blades were carried out using a 200 mm bore single suction pump installed in a closed circuit system. Flow inside the impeller was observed with strobo-light, and the NPSH at the condition of cavitation incipience measured for each impeller was found to show a peculiar variation against capacity taking a minimum at or near the designed flow rate and a peak at a partial capacity. The flow at the impeller inlet was measured with a Pitot tube and it was clarified that the flow pattern which accompanied remarkable swirling and back flow at partial capacities was responsible for the above NPSH variation. The cavitation aspects in the impellers are presented by photographs and their correlations with the various local pressure drops are discussed. The impellers were compared in terms of pressure drop coefficients as well as the suction specific speed plotted versus capacities with a view to applying them to the practical fields.

15 citations


Journal ArticleDOI
TL;DR: In this paper, the free convection boundary layers of ethyleneglycol or water along a vertical cylinder are observed, and a laminar layer transits to a vortex street layer at GrPr≒4×109, and then to a turbulent layer at grPr ≥1010.
Abstract: The free convection boundary layers of ethyleneglycol or water along a vertical cylinder are observed. A laminar layer transits to a vortex street layer at GrPr≒4×109, and then to a turbulent layer at GrPr≒1010. In the vortex street layer, the geometrical configuration of which is similar to that of Karman vortex street, the pitch of the vortices and the number of the vortices developed per unit time are kept constant respectively. Then it is tried to analyse these experimental data theoretically. Though the theory is very simple, the results are in nearly good agreement with the experimental data.

12 citations



Journal ArticleDOI
TL;DR: The tension problem of an infinite plate containing an infinite row of circular holes was first solved by R.C.J. Howland as discussed by the authors, and the numerical results of the circumferential stress are given in forms of power series.
Abstract: The tension problem of an infinite plate containing an infinite row of circular holes was first solved by R.C.J. Howland. In the present paper, the author treats other important plane problems of the same plate, that is, uniform tension, tension in arbitrary direction, uniform shear, bending in plate, uniform internal pressure, cos-type internal pressure and sin-type internal pressure. Formulas of the circumferential stress are given in forms of power series and the numerical results are examined.

Journal ArticleDOI
TL;DR: In this paper, a theory of grease lubrication for cylindrical roller bearing has been deduced, considering the grease as a Bingham plastic, and the special core formation in grease film, the frictional resistance of rolling bearing, the pressure distribution and the load capacity of grease film entrapped between roller and race of cylinder roller bearing have been investigated.
Abstract: The lubrication theory on the substances of rheological behaviour as grease is a recent theme. In particular, as the grease is often used for the lubrication of rolling bearing, it is important to establish a theory of grease lubrication for rolling bearings. In this paper, considering the grease as a Bingham plastic, a theory of grease lubrication for cylindrical roller bearing has been deduced. That is, the special core formation in grease film, the frictional resistance of rolling bearing, the pressure distribution and the load capacity of grease film entrapped between roller and race of cylindrical roller bearing have been researched. In addition, the above grease lubrication theory is compared with the oil lubrication theory.

Journal ArticleDOI
TL;DR: In this article, the authors have carried out some experiments about rolling fatigue accompanied with sliding, and investigated how fatigue cracks occur and progress, and found that fatigue cracks progress with the speed of sliding.
Abstract: The problem of fatigue phenomena under rolling contact accompanied with sliding is very important for the gears, rails and tyres, rolling bearings etc., nevertheless little part of the problem has been revealed. So we have carried out some experiments about rolling fatigue accompanied with sliding, and investigated how fatigue cracks occur and progress.


Journal ArticleDOI
TL;DR: In this paper, the temperature measurement of the piston surface was performed on a four-stroke spark-ignition engine with a water-cooled single cylinder, bearing-stroke being 114.3×140 mm and output is 6 HP at 850 r.p.m.
Abstract: This report deals with temperature measurement of the piston surface. The test engine used is a four-stroke spark-ignition engine with a water cooled single cylinder, bore×stroke being 114.3×140 mm and its output is 6 HP at 850 r.p.m. The iron-constantan thermocouple is used and its hot junction is located in the surface center of the aluminium-alloy piston head. In order to measure accurately the periodic temperature change, the hot junction is constructed with the metallic film. Two wires-iron and constantan-are electrically insulated and let to the piston surface, and there they are shorted by the metallic film. The film is constructed successfully with the aluminium metallikon. For connecting the thermocouple to the amplifier, the input transformer is used. By these methods, the temperature change of the aluminium-alloy piston has been measured without being disturbed by the spark plug.

Journal ArticleDOI
TL;DR: In this paper, a few new metal cutting methods, Sub-Zero Cutting, Reversal Finish Cutting and Ultrasonic Cutting, are described, which may produce an excellent surface having a lower roughness and a smaller depth and magnitude of work hardening, even under a low cutting velocity.
Abstract: This paper describes a few new metal cutting methods-Sub-zero Cutting, Reversal Finish Cutting and, Ultrasonic Cutting which may produce an excellent finished surface having a lower roughness and a smaller depth and magnitude of work hardening, even under a low cutting velocity. In the ordinary machining, on account of the cohesive friction produced at the tool-chip and tool-work interfaces, the surface layer is dragged by a cutting edge of a tool and the surface finish becomes inferior. In the Sub-zero Cutting, the cohesive friction may be prevented by cooling both of the tools and the work below zero temperature and a fine finished surface may be gotten. The Reversal Cutting Finish is a method which may produce a smooth surface by taking advantage of the cohesive friction and it is performed by adding the last slight finish cutting having the reversed direction of cut to one of the basic cutting. The Ultrasonic Cutting is carried out by applying the ultrasonic vibration to tools or works. All of these would be more effective for cutting the ductile materials, because the cohesive friction is easy to occur, especially under low speed.

Journal ArticleDOI
TL;DR: In this article, the tension in an orthotropic strip with a circular hole is treated and the free edge conditions at the rim and of the circular hole and the stresses are given in the form of the power series of λ which is the ratio of the radius of the circle to the half breadth of the strip.
Abstract: In this paper, the tension in an orthotropic strip with a circular hole, which has practical importance, is treated. The solution of the same subject for isotropic material, has been presented by R.C.J. Howland and lately improved by M. Isida to study the stresses in a strip with an elliptic hole by the use of orthogonal co-ordinates. In this paper, the same methods are adopted to express the free edge conditions at the rim of the strip and of the circular hole and the stresses are given in the form of the power series of λ which is the ratio of the radius of the circular hole to the half breadth of the strip.


Journal ArticleDOI
TL;DR: In this article, the Bernoulli-Euler equation for the elastica of thin rods is extended to the center line of coiled springs and the deflection curve is discussed.
Abstract: The deflection curve of the center line of coiled springs is discussed, expanding the Bernoulli-Euler equation for the elastica of thin rods. Numerical results and their comparison to the experimental values are presented.

Journal ArticleDOI
TL;DR: In this paper, the authors carried out some experiments to find out the behavior of oil leakage from an O-ring packing used for the gasket and reciprocating parts, and the results showed that the seals can be made perfectly leakproof for oil pressure up to 280 kg/cm2 (the limit of this test pressure).
Abstract: We have carried out some experiments to find out the behaviour of oil leakage from an O-ring packing used for the gasket and reciprocating parts. The chief points of the results of this investigation are : i) For the gasket : The seals can be made perfectly leakproof for oil pressure up to 280 kg/cm2 (4000 psi limit of this test pressure). ii) For the reciprocating use : It has been shown theoretically and proved experimentally that the quantity of oil leakage from an O-ring is proportional to the square of the reciprocating velocity of the road, the n-th power of the kinematic viscosity of the oil. In this case we have n≒1 for the values of ν measured at the working pressure from analytical treatment but n=1.5 for ν measured at atmospheric pressure from experimental results.

Journal ArticleDOI
TL;DR: In this article, the boundary layer equations with certain assumptions introduced into them were solved, and two different solutions were given, the one with similarity of temperature and velocity profile in boundary layer, the other with a 160 Reynolds number of laminar sublayer as a fundamental assumption.
Abstract: Experimental findings were made clear by solving approximately the boundary layer equations with certain assumptions introduced into them. Two different solutions were given, the one with similarity of temperature and velocity profile in the boundary layer, the other with a 160 Reynolds number of laminar sublayer as a fundamental assumption. The former corresponds to transient turbulent flow and the latter to turbulent flow respectively. Heat-transfer coefficients were given in the following formulas : Transient turbulent flow, [numerical formula] Turbulent flow, [numerical formula] where, [numerical formula]

Journal ArticleDOI
TL;DR: In this article, the authors measured the noises of three kinds of simple single row deep groove ball bearing, analyzed the peak values of their frequency spectrums, and obtained the results as follows : (1) the noise of a simple ball bearing is due to vibrations of the outer ring.
Abstract: There are many researches on the noise of a ball bearing, and their conclusions about noise source can be divided into two main opinions ; one attributes it to elastic vibrations of the outer ring, the other to vibrations of the cage or ball. However, these conclusions are only based on a hypothesis. So, in the first place, the author measured the noises of three kinds of simple single row deep groove ball bearing, analyzed the peak values of their frequency spectrums, and obtained the results as follows : (1) The noise of a simple ball bearing is due to vibrations of the outer ring. (2) In the above vibrations, there are radial and axial bending ones which have the first and the second modes. (3) In the case of axial load, another vibration exists, and its vibratory system which was found by Mr. Tanaka, consists of a mass of outer ring and an axial stiffness of ball bearing.

Journal ArticleDOI
TL;DR: In this article, the authors describe the behavior of the chip in steel cutting by the lathe tool with the parallel type chip breaker, which is the most fundamental type of chip breaker.
Abstract: This paper describes the behaviour of the chip in steel cutting by the lathe tool with the parallel type chip breaker, which is the most fundamental type of the chip breaker. The first half describes about the curling radius of the chip bent by the chip breaker. We present here a new equation about the curling radius. The latter half describes about chip breaking by the chip breaker. Using the above equation of the curling radius, we succeeded in an equational representation of the conditions in which the chip is properly broken. On the basis of this equational representation, a chart was drawn up for the design of the chip breaker.

Journal ArticleDOI
TL;DR: In this article, a diesel engine with both fine-bored and honed cylinders was tested and it was shown that the wear of a honed cylinder is smaller than that of a fine-borored cylinder at initial stage, but with regard to the total wear, there is no difference between them.
Abstract: To make fully sure about the effect of honing, the authors tested with a diesel engine which had both fine-bored and honed cylinders. Careful investigations were made on 1) cylinder : amount of wear (as measured by the air-micrometer), roughness 2) piston : amount of wear of piston and ring grooves, distribution of temperature 3) piston ring : amount of wear, tension, distribution of pressure, movement in cylinder, roughness and 4) compression pressure. After one year and a half measurement, the following conclusions have been reached : 1) Wear of a honed cylinder is smaller than that of a fine-bored cylinder at initial stage, but with regard to the total wear, there is no difference between them. 2) In other respects, there is no difference between them either. 3) So honed ordinary cast iron cylinders shorten the fitting time, but fine-bored cylinders serve the purpose in other respects.

Journal ArticleDOI
TL;DR: In this article, the problem of a rectangular plate with clamped or supported edges is treated by means of the undetermined multiplier method in the calculus of variations, and the amplitude or the displacement of the plate is expressed by the double Fourier series, then by the orthogonality of the trigonometric functions.
Abstract: The problem of a rectangular plate with clamped or supported edges is treated in this paper by means of the undetermined multiplier method in the calculus of variations. The amplitude or the displacement of the plate is expressed by the double Fourier series, then by the orthogonality of the trigonometric functions, numerical calculations become very simple and many types of problems-natural and forced vibrations, statical deflections, bucklings and others-can be easily solved through the unifled and systematic procedures of calculations.

Journal ArticleDOI
TL;DR: In this article, the tension problem of an infinite strip containing a square hole with rounded corners is treated by the method of perturbation, convenient formulas for the stress are given and numerical results are examined.
Abstract: The tension problem of an infinite strip containing a square hole with rounded corners is treated by the method of perturbation, convenient formulas for the stress are given and numerical results are examined. The concept of "equivalent elliptic hole" given by F. Hirano in problems of perforated infinite plates is found to be not so valid for the present strip problem. On the other hand, the approximate method proposed by the author in case of an elliptic hole is still applicable to this problem. In this connection, the author gives an advice on applying this method to other problems of multi-connected regions.

Journal ArticleDOI
TL;DR: In this article, a 0.55 percent carbon steel and a 13 chromium steel were used to study the influence of frequency of stress repetition on the fatigue strength of materials, and it was shown that at large amplitude, the specimens fractured at a definite number of stress cycles irrespective of frequency and, at a smaller amplitude, specimens tested at lower frequency fractured at less cycles than those at higher frequency.
Abstract: Rotating bending fatigue tests under constant strain amplitude were carried out with a 0.55 percent carbon steel and a 13 chromium steel to study the influence of frequency of stress repetition on the fatigue strength of materials. The test temperature was from 450°C to 600°C and the frequencies of stress cycles were 170 and 1500 c.p.m. Both the 0.55 percent carbon steel and the 13 chromium steel showed the fatigue behavior characteristic to the elevated temperature above a critical temperature. That is, at a large amplitude, the specimens fractured at a definite number of stress cycles irrespective of frequency and, at a smaller amplitude, specimens tested at lower frequency fractured at less cycles than those at higher frequency. These characteristics are the same as those of low carbon steel studied previously, and suggest that the fatigue at elevated temperatures is a sort of rate processes and is closely related with the plastic deformation of material under alternating load. Interpretations were made on the common basis with the dynamic creep rupture.

Journal ArticleDOI
TL;DR: In this paper, the cavitation limits concerning the incipience on the blade and variation in pump performance are presented against the flow rate in terms of the parameter σs as well as in the suction specific speed.
Abstract: Cavitation tests on an axial flow pump were made over a wide range of operating conditions. Through these tests, the aspects of cavitation in the impeller were observed with a strobolight and variation of the pump characteristics was studied. A parameter σs to represent the suction condition was introduced to give the cavitation limits for any flow rate. The pump head showed little change until the cavitation on the blade surface was developed considerably, while the shaft horse-power began to increase slightly with the incipient cavitation on the blade, decreasing abruptly as the pump head dropped due to the growth of cavitation. So that the efficiency showed gradual decrease as the incipient cavitation grew. The cavitation limits concerning the incipience on the blade and variation in pump performance are presented against the flow rate in terms of the parameter σs as well as in the suction specific speed.

Journal ArticleDOI
TL;DR: In this paper, the authors used the concept of the "mechanical equation of state in solid" with an error not exceeding 10 percent to predict the creep strain of carbon steel at high temperatures.
Abstract: Creep tests were made with 0.14 percent carbon steel at 450°C under periodic stresses, changing stepwise between two stress levels, the mean of which was 17.0 kg/mm2 and the stress amplitude of which was 1.0 or 2.0 kg/mm2. It was found that, under the test conditions in this study, creep strain under varying stresses could be predicted from the data of constant stress creep tests by applying the concept of the "mechanical equation of state in solid"with an error not exceeding 10 percent. The limitations of the "mechanical equation of state"as a practical method of estimation of the strain under varying stresses were discussed on the basis of the authors' theory of plastic deformation of metals at high temperatures, in which the effect of stress and temperature history was taken into account.