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Motoyoshi TACHIBANA, Hirokazu GENNO
1985 Volume 51 Issue 470 Pages
3079-3082
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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In the inlet region and the fully developed region of rectangular duct, the axial pressure drop due to a steady laminar flow of non-Newtonian power law fluid was measured by the multi-tube manometer and the theoretical analysis in our previous paper was discussed on the basis of present experimental result. From this finding, it can be considered that our theoretical analysis is useful to predict the pressure drop in the inlet region of rectangular duct.
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Yuri AOYAMA, Yoshihiro MATSUOKA
1985 Volume 51 Issue 470 Pages
3083-3091
Published: October 25, 1985
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Yoichiro IRITANI, Nobuhide KASAGI, Masaru HIRATA
1985 Volume 51 Issue 470 Pages
3092-3101
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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Hideo OSAKA, Yoshiro KAGEYAMA, Satoru OYAMA
1985 Volume 51 Issue 470 Pages
3102-3109
Published: October 25, 1985
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Osamu MOCHIZUKI, Hideo YAMADA, Haruo YAMABE, Motomu IMAIZUMI, Atsuhiro ...
1985 Volume 51 Issue 470 Pages
3110-3118
Published: October 25, 1985
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Yutaka YAMADA, Shigeki IMAO, Motoaki TODA, Takahiro KIMURA
1985 Volume 51 Issue 470 Pages
3119-3127
Published: October 25, 1985
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Haruo YAMABE, Youji ANDOU, Osamu MOCHIZUKI, Hideo YAMADA
1985 Volume 51 Issue 470 Pages
3128-3136
Published: October 25, 1985
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Michihisa TSUTAHARA, Takeyoshi KIMURA
1985 Volume 51 Issue 470 Pages
3137-3144
Published: October 25, 1985
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Akira OHASHI, Katsuya YANAIDA
1985 Volume 51 Issue 470 Pages
3145-3154
Published: October 25, 1985
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Takeshi NAKADA, Toyokazu MITSUOKA
1985 Volume 51 Issue 470 Pages
3155-3164
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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Shigefumi NISHIO
1985 Volume 51 Issue 470 Pages
3165-3173
Published: October 25, 1985
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Shoichiro FUKUSAKO, Nobuhiro SEKI, Seigo ISHIGURO, Shun NOZAWA
1985 Volume 51 Issue 470 Pages
3174-3182
Published: October 25, 1985
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Hideo INABA, Takeyuki FUKUDA
1985 Volume 51 Issue 470 Pages
3183-3190
Published: October 25, 1985
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Hiroshi HONDA, Shigeru NOZU
1985 Volume 51 Issue 470 Pages
3191-3198
Published: October 25, 1985
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Tadashi YAMAMOTO, Yoshio TANAKA
1985 Volume 51 Issue 470 Pages
3199-3207
Published: October 25, 1985
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Hiroshi MAKI, Kohoich SUZUKI
1985 Volume 51 Issue 470 Pages
3208-3214
Published: October 25, 1985
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Masashi KATSUKI, Yukio MIZUTANI, Akira OHTA, Byeong-Ryun CHOI
1985 Volume 51 Issue 470 Pages
3215-3222
Published: October 25, 1985
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Kazuie NISHIWAKI, Gen'ichi KOMATSU, Makoto IKEGAMI
1985 Volume 51 Issue 470 Pages
3223-3231
Published: October 25, 1985
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Tsuguo KONDOH, Atsuo FUKUMOTO, Katsuyuki OHSAWA, Katsuhiko SUGIYAMA
1985 Volume 51 Issue 470 Pages
3232-3242
Published: October 25, 1985
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Masaru OGURA, Toru YONEZAWA
1985 Volume 51 Issue 470 Pages
3243-3251
Published: October 25, 1985
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Kazuhiko NAGASE, Yoshijiro FUKUSHIMA
1985 Volume 51 Issue 470 Pages
3252-3262
Published: October 25, 1985
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Michihiko TABATA, Masataka ARAI, Hiroyuki HIROYASU
1985 Volume 51 Issue 470 Pages
3263-3271
Published: October 25, 1985
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Yoshio FUJIMOTO, Toyohiko SUZUKI, Yoshitaka OCHIAI, Hiroshi KAGEYAMA
1985 Volume 51 Issue 470 Pages
3272-3280
Published: October 25, 1985
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Hiroshi IWATA, Akio SAKAZUME
1985 Volume 51 Issue 470 Pages
3281-3284
Published: October 25, 1985
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Keiichi SATO, Yukio ITO, Hideto MIYAKURA, Toshiaki IKOHAGI, Risaburo O ...
1985 Volume 51 Issue 470 Pages
3285-3290
Published: October 25, 1985
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The appearance of cavitation and the characteristics of cavitation acoustic pulse are investigated about decelerated flow as well as accelerated flow in blowdown-type cavitation tank without recirculating water. The pressure pulses are monitored by measuring the peak pulse amplitude in a long orifice, where separation bubbles are formed but the remarkable hysteresis effect is found. The appearance of cavitation is well correlated with the count-rate of pressure pulses and the acoustic energy level. The count-rate of pressure pulses is related qualitatively with the total acoustic energy of pressure pulses and it varies exponentially with the threshold level. The extent of cavitation in growth is devided in several stages from the appearance of cavitation and the characterics of pressure pulses.
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Ikuo NAKAMURA, Yoshinori UEKI, Shintaro YAMASHITA
1985 Volume 51 Issue 470 Pages
3291-3296
Published: October 25, 1985
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An experimental study has been performed on the structure of turbulent flow around a cylinder spinning in a quiescent fluid. The visualization using smoke wires and the method of thermal tuft have revealed that the reverse flow exists not in the internal region but in the external region of the cylinder. The reverse flow occurs in the same region as the eddies which can be found by scattering aluminum powder. It has been found that the eddies displayed by the picture of aluminum powder, which was taken by a rotating camera grew larger and larger in propagation to the distance from the cylinder. Also the mixing length grows longer and longer just as above. The radial length of eddies almost agrees with the mixing length. Furthermore, the turbulent diffusion of the instantaneous spot in the dropping of dyes has been examined. The examination has shown that the scale of diffusion has a strong correlation with that of the peripheral length of eddies.
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Hiroya YAMADA, Ikuo NAKAMURA, Shintaro YAMASHITA, Haruhisa YANO
1985 Volume 51 Issue 470 Pages
3297-3302
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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An experimental study has been performed on the mean flow properties of the two-dimensional impinging jets on a wedge whose included angle is 90°. The variations in static pressure along the streamwise and transverse directions are large near the vertex of the wedge, and should not be neglected in calculations for these flows. The non-dimensional velocity profiles in the fully-developed-flow region far from the vertex do not coincide with the similarity profile of the two-dimensional wall-jet. Also the trends in the decay of the maximum velocities and in the growth of the half width of the present wall-jets are different to those of the two-dimensional wall jets. The local skin friction coefficients are estimated and compared with the empirical formula proposed by several authors. The logarithmic velocity distribution is examined by using the estimated values of the skin friction coefficients.
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Yooichiro SAWA, Nobuharu MORII, Hideo MATSUDAIRA
1985 Volume 51 Issue 470 Pages
3303-3307
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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This paper deals with linearization of the seal water oscillation system. In this proceduce, the authors introduce a phenomenal time which changes with the intermittent seal water flow. When the seal water behavior is observed on the scale of this phenomenal time, the non-liner oscillation system can be treated as a linear one : 1) The motion of the gravitational center in the seal water corresponds to second-order oscillation. 2) The sea water flow corresponds to the response of first-order lag component. 3) Thy are described as a linear combination. Thus, the linear system makes it simple to analyze the dynamic performance of drain traps.
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Osamu MOCHIZUKI, Hideo YAMADA, Haruo YAMABE
1985 Volume 51 Issue 470 Pages
3308-3311
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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We investigated the properties of a planar jet in which a cylindrical body was set on the center line of the jet near the nozzle. The spread of the jet and some flow properties, particularly behind the cylinder in the jet, were measured for four kinds of cylindrical bodies of different shapes. The downstream as follows: (1) The spread angle of the jet changes considerably with an increase in location of a maximum angle exists there. (1) In the wake region, the generation of the tone due to interaction between the jet and the cylinder plays a crucial role on the flow properties, rather than the shapes of the cylinder.
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Hikaru MATSUMIYA, Yasukata TSUTSUI, Yukio KUMEOKA
1985 Volume 51 Issue 470 Pages
3312-3316
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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An investigation of 8 kinds of wings was mad in the wind tunnel of the mechanical engineering laboratory around the practical range of Reynolds Number, in order to determine the optimum shapes suitable for the tail-wings of small-scale wind turbines out of a number of various shapes practically used in the world. As the wind changes direction more than 20 degrees instantaneously, often 30 or 40 degrees an optimum tail-wing must have such characteristics that keep the high-lift coefficient in the region of large angles of attack, preventing itself from falling in a stall. A coefficient of yaw-control force, acting on the tail-wing perpendicular to its surface, was defined to compare the characteristics of the wings as tail-wings. It is concluded that the wings of an aspect ratio of 1.5-0.7 are superior to those of a large aspect ratios.
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Yasuki NAKAYAMA, Akinobu HAGIWARA, Hiroaki OHTA
1985 Volume 51 Issue 470 Pages
3317-3322
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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Experiment were performed on rectangular take-off ducts of three types and eleven different shapes. The change in shape of the ducts has a small effect on the coefficient of branch loss for the main flow, but it has a large effect on the branch flow. The molding the upper side of the branch edge has a large effect in making the coefficient of loss small compared with rounding the down-side. This corner modeling effect on take-off ducts was confirmed also by the tuft method. By these results, the rectangular straight take-off ducts was confirmed also by the tuft method. By these results, the rectangular straight take-off ducts with an installation face were developed for the purpose of rationalizing production for the modernization and ease of manufacture.
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Yutaka TSUJI, Yoshinobu MORIKAWA, Wataru SEKI
1985 Volume 51 Issue 470 Pages
3323-3327
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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It was attempted to control the capsule velocity during a run by changing the area of an end plate which had some notches. First, an empirical formula of the fluid drag on the capsule was derived, which was compared with measurements. The experiment of velocity control showed that deceleration was slower than acceleration. Calculations of the capsule motion gave good agreement with the experimental results in the case of acceleration. However, in the case of deceleration. the experimental results showed more gradual decrease in velocity than the calculations.
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Kotohiko SEKOGUCHI, Masayuki TAKEISHI, Kazuhiro YAHIRO, Kenji TAKAHASH ...
1985 Volume 51 Issue 470 Pages
3328-3335
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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A statistical method is proposed to express the characteristics in interface on various sizes of liquid lumps appearing both in froth flow and huge wave regimes. According to cross-sectional mean liquid holdup traces, the interfacial structures were assumed fundamentally to consist of base wave and liquid slug or huge wave. The determining procedures of the shape factors and probability density of wave crests for these liquid lumps are explained. In addition, typical examples of applying this method into air-water two-phase upward flow in a 18.0 mm inside diameter tube are presented.
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Takakage ARAI, Hiroyuki HASHIMOTO
1985 Volume 51 Issue 470 Pages
3336-3343
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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The breakup of thin liquid sheet in a cocurrent gas stream was investigated experimentally. The patterns of the disintegration were classified mainly into two breakup patterns. The first breakup means that the liquid film disintegrates into lumps, ligaments and droplets, and the second breakup means that the large lumps, ligaments and large droplets produced by the first breakup breakdown into the smaller droplets. Moreover, the first breakup was divided into the following four small groups : lump, ligament, bag. These breakup depended strongly on the wave motion of the liquid sheet. The scale, shape and instability (possibility of realization of the second breakup) of large lumps and droplets varied with the type of the breakups. It was also clarified that the breakup of thin liquid sheet in a high speed gas stream was caused mainly, not by an unbalance of the surface tension and the liquid flow momentum in the liquid sheet, but gas flow impact on the surface of the thin liquid film having large wave amplitude.
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Takashi WATANABE
1985 Volume 51 Issue 470 Pages
3344-3347
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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A theory is investigated for the linear stability analysis of a three-dimensional rotating disk flow, in which the effects of Coriolis forces and streamwise curvature are included. The resulting six-order system describing the spatial evolution of the disturbances is solved numerically according to the Adams-Bashforth method, and the stability curves are presented for various numbers of vortices. The results show that the critical Reynolds number for the spiral vortices flow is 285, and the angle of the vortices is about 14° with the outward-down radius vector for 30 vortices. However, the critical Reynolds number is 252 and the number of vortices is 16 in the case of no phase velocity. Wereas, for 16 vortices, different instability mechanisms are obtained in which the angle of the vortices is about 20°.
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Toshio YOKOYAMA, Yukio TOMITA
1985 Volume 51 Issue 470 Pages
3348-3354
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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Experiments on flows of water and dilute aqueous solution of polyethylene oxide are carried out over the Reynolds number range of 10
3 to 5×10
4. Concentration of polymer solutions is varried from 1 ppm to 100 ppm. The ratios of curvature radius to pipe radius R/a are 18.7, 34.3 and 47.3. Measured pressure distributions along a bend axis are classified in three types by their patterns. Flow property of each pattern is clarified by using the method of flow visualization. Drag reduction in bend flow is smaller than that in straight pipe flow. Pressure loss coefficients are correlated with the Reynolds number, the ratio of radius R/a, and the Wissenberg number. The empirical formulas presented for the bend loss coefficient are useful from an enginnering viewpoint.
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Yoshiyuki NAKASE, Junichiro FUKUTOMI, Takashi WATANABE, Yoshio YAMAMOT ...
1985 Volume 51 Issue 470 Pages
3355-3359
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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It is very difficult to analyze the flow on the bucket of a Pelton wheel. Therefore, the design an the efficiency estimation of Pelton turbines are based on the momentum theory and experimental data. In this report, a method of analyzing steady, three-dimensional, nonviscous flow on the bucket of a Pelton wheel is shown. In order to manage the analysis, it is assumed that the thickness of the flow on the bucket is very thin, and there are no viscous effects in this first report. Numerical examples for some flow conditions are included.
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Terushige FUJII, Koji AKAGAWA
1985 Volume 51 Issue 470 Pages
3360-3365
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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Water hammer phenomena caused by a sudden value closure are considered in two-component bubbly flows where the phenomena are more complicated than those in single-phase flows because of the presence of the compressible component. Basic partial differential equations based on a one-dimensional homogeneous flow model are solved analytically by linearization and iterated Laplace transformation. As a result, the profiles of the pressure transients, the propagation velocity of a pressure wave with a small amplitude, and the effects of valve closure on transient pressures are found. Further, the effect of friction factor on pressure profiles is shown and approximated by a simple equation. It is also shown that reflection and transmission occur at the interphase where the void fraction changes.
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Masakazu HOSHINO, Hiroshi OHKI, Yoichi YOSHINAGA
1985 Volume 51 Issue 470 Pages
3366-3369
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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Partial height guide vanes are adopted to improve non-uniformity of the diffuser flow in high specific speed centrifugal compressors. In order to get the optimum guide vane height, pressure and velocity fields were measured for five kinds of guide vanes using laser-two-focus velocimeter. The diffuser with guide vanes whose height is 40% of the diffuser width shows the best pressure recovery : its increment is 10% compared with the diffuser without guide vanes. The measurement of the velocity fluctuation in the diffuser reveals that the fluctuation decreases rapidly between the impeller outlet (D
2) and 1.1×D
2, decreasing slowly thereafter.
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Takashi AWAI, Tomohiro NAKAGAWA, Toshimichi SAKAI
1985 Volume 51 Issue 470 Pages
3370-3375
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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From the view point of machine dimension, the axially curved mixed-flow diffuser has a large benefit compared with the purely conical or the radially curved mixed-flow diffuser. In the present study, the flow pattern and pressure recovery in the axially curved mixed-flow diffusers are experimentally examined, and the result are compared with those of the purely conical diffusers. The pressure recovery factor and diffuser effectiveness of the axially curved diffuser showed a lower performance compared with the purely conical diffuser, but the difference was small. By use of a guide fence at the inner wall, flow in the axially curved diffuser was rectified and a favorable performance was obtained.
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Tomitaro TOYOKURA, Kenichi SUZUKI, Toshiaki KANEMOTO, Toshinori KASHIW ...
1985 Volume 51 Issue 470 Pages
3376-3380
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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Diffuser performance for the two-phase flow of air-water mixture has been scarcely examined, though that for the mono-phase flow has been examined and the optimum profile given. The diffuser performance for the two-phase flow is affected non only by the diffuser profile, but also by the diffuser inlet velocity. Thus, this report aims to make clear these effects on the performance for an air-water mixture ratio 0-0.15m and to decide the desirable profile and inlet velocity. The performance deteriorates as the mixture ratio increase, but the optimum inlet velocity exists for each mixture ratio and diffuser profile. The best performance is obtained when the diffuser length-width ratio 1/W is about 7 in spite of the mixture ratio. At 1/W = 7, the optimum divergent angle and inlet velocity are also given.
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Tadashi SAWADA, Masahide NAKAMURA
1985 Volume 51 Issue 470 Pages
3381-3385
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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A Spiral grooved vacuum pump which works in the pressure range from 1 to 1000 Pa is studied theoretically and experimentally. The flow in grooves and ridges and ridges on the pumping rotor is treated as a slip flow, and Boon and Tal's " Narrow groove theory" developed for viscoseals is used. The theoretical predictions show good agreement with the experimental results. Suggestions are made regarding the choice of design parameters, i.e., aspect ratio, helix angle, clearance parameter and groove width ratio.
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Daisuke KONNO, Seiyo MAEKAWA, Asahiro WAKIGAWA
1985 Volume 51 Issue 470 Pages
3386-3391
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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The slip of pump feet on the baseplate caused by piping loads was investigated. The test pump was axially-split, single-stage, double-suction volute type with foot support. The static coefficient of friction between the pump foot and baseplate ranged between 0.15 and 0.35, The effects of dowel pins and jack screws against the slip were also investigated. Furthermore, shaft displacements due to the deformation of pump casing and baseplate were measured. In the case of test pumps, the proportion of the shaft displacement due to casing deformation to that of pump assembly was 50% and more in most load conditions. Then, the rigidity of not only the baseplate but also the pump casing must be increased when large piping loads over API loads are specified.
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Hajime FUSE, Takayuki OYAMA, Osami NIIHARA, Yuhki UCHIYAMA
1985 Volume 51 Issue 470 Pages
3392-3396
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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The effects of low frequency components of free-stream turbulence on heat transfer in the separated region of a cylinder were experimentally investigated for a Reynolds number range from 7.0×10
3 to 2.4×10
4 at the free-stream turbulence intensities of T
u < 0.5%. The experiments were carried out under constant heat flux conditions and two kinds of low frequency components of free-stream turbulence. The shape of separated shear layer, power spectrum of fluctuating velocity in the shear layer and pressure distribution around a cylinder were also measured. It is found that heat transfer in separated flow depends upon the diffusion of the separated shear layer. When the separated shear layer is thick and the effect of diffusion is large (Pattern Ap), heat transfer rate increases and vice versa ( Pattern Bp). "Transition" from Pattern Bp to Pattern Ap depends upon low frequency components of free-stream turbulence.
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Koichi ICHIMIYA, Masato YOKOYAMA
1985 Volume 51 Issue 470 Pages
3397-3403
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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Heat transfer characteristics on the smooth heated surface, opposite the roughness elements on the insulated wall, were experimentally determined by flowing air through a parallel plate duct and by changing the shape of the roughness elements. The most developed heat transfer coefficients were obtained as functions of Re and the size of roughness elements for the optimum pitch. The correspondence between heat transfer and flow situation revealed that the effects of the acceleation and the turbulence, produced on the smooth heated surface, were different for each shape of the roughness elements. These effects contributed to the increase of local heat transfer.
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Shigefumi NISHIO
1985 Volume 51 Issue 470 Pages
3404-3410
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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In this report, the correlation technique of conditions at minimum heat flux point (ΔT
M, q
M) for saturated boiling proposed by the author in the previous report is compared with experimental data for the effects of surface-geometry and system-pressure. Experiments to measure ΔT
M and q
M on horizontal cylinders of 0.39.6 mm in diameter are conducted for nitrogen and water at atmospheric pressure. The experimental results show that ΔT
M is almost independent of surface-geometry and is in good agreement with the author's correlation. This is confirmed also by the experimental data reported by Hein et al. for a downward facing conical surface at high system-pressures. Minimum heat fluxes on various surface-geometries for nitrogen, water, freons and isopropanol are estimated using existing correlations of fully developed film boiling and the author's correlation of ΔT
M. They are compared with a number of experimental data and it is confirmed that the present correlation technique is available as a tool for estimating the effects of surface-geometry and system-pressure on minimum heat flux.
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Saburo TODA, Koichi SUGIYAMA
1985 Volume 51 Issue 470 Pages
3411-3420
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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The laminar flow heat transfer in a tube with internal solidification has been investigated theoretically and experimentally. The variations of local heat flux, velocity profile of fluid and solid-liquid interface profile of frozen layer during freezing were determined numerically as a function of time and position along the tube. The steady state heat transfer rates and solid-liquid interface profiles calculated showed better approaches to previous experimental data which, however, had considerable deviations with the earlier theory, mainly produced by free convection. Experiments were carried out for water flowing in a vertical tube within the range of R
e = 1001600. The results confirmed and strenthened the effects of solidification upon laminar flow heat transfer that arose from the three dimensional heat conduction in the frozen layer and the liquid velocity profile deformed through the channel contracted with the solidified layer. Experimental data agreed well with the present numerical analyses, and showed the effects induced by liquid supercooled and flow transition from laminar to turbulent due to unstable growth of frozen layer.
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Yuji OGAWA, Toshifumi KONDO, Shiro TAKI
1985 Volume 51 Issue 470 Pages
3421-3425
Published: October 25, 1985
Released on J-STAGE: March 28, 2008
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An experimental technique is developed to investigate the deflagration to detonation transition of gaseous mixtures in an unconfined space. Diluted stoichiometric ethane-oxygen mixtures are supported in atmosphere bounded by soap bubbles. Turbulences made by grids placed repeatedly in combustible gas mixtures intensify the burning, which causes acceleration of the flame and pressure waves. Transitions to detonations are observed in an unconfined space. If the shock waves are strong enough to make self-ignition, then a detonations occurs. A plane wall placed parallel to the direction of the flame propagation helps to make the condition of self-ignition. Critical conditions for transition to detonation depend on the heat release rate, intensity of turbulence, and boundary, which are related to each other.
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