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application/pdf, This paper is a part of the experimental investigations on the characteristics of the Flow around flat plates vertically immersed in turbulent boundary layers. In the first and second papers，were the characteristics of the flow around a flat plate i.e. the distributions of velocity and pressure， the flow patterns and interference effects of the tunnel walls on the form drag， discussed. In the present paper， correlations are obtained for the variation of the form drag of double flat plates with the distance of the flat plates and the characteristics of the boundary layer in which it is vertically mounted.

application/pdf, This paper is a part of experimental investigations on the characteristics of the flow about flat plates vertically immersed in turbulent boundary layers. In the first paper，the characteristics of the flow about a flat plate i.e. the distributions of velocity，pressure and the now patterns， were discussed. The present paper describes both theoretically and experimentally the interference effects of the tunnel walls on the behavior of the streamline separated from the edge of the plate， together with the variation of the form drag of the plate.

application/pdf, The present paper describes the mean-flow patterns, distributions of the mean velocity and turbulence intensity in the wake behind the normal plates immersed in a smooth-wall turbulent boundary layer with zero-pressure gradient. The effect of a parameter h/δon the mean-flow patterns and distributions of the mean velocity in the wake is examined in some detail, where h and δ are respectively the height of the normal plate and the boundary layer thickness. The main results will be summarized as follows : (a) The geometrical shape of the rear standing eddy and the reattachment point of the separated flow are not very much influenced by the parameter h/δ. (b) The mean velocity profiles in the rear separation eddy are closely approximated by the velocity profile in a constant pressure half-jet theoretically obtained by Goertler. (c) A maximum turbulence intensity in the wake behind the normal plate occurs along the flow separated from the top edge of the plate.

application/pdf, The seepage flow through porous media under a hydraulic structure belongs to the confined flow problems, to which the conformal transformations have been applied by many hydraulic engineers. However, when there are more than three sheet-pilings on the bottom of foundation, the analytical method is not effective. In this paper, we deal with such a case that a seepage flow field is symmetric with respect to the y axis (as in Fig. 1(a)). As a result, the uplift pressure distribution on the base of structure is symmetrical to the center of an uplift pressure diagram regardless of the number of cutoff and the total uplift force is equal to the value integrated on condition that uplift pressure distribution is linear.

application/pdf, This paper presents a method for optimizing power flow with line security limits, as the more generalized optimization problem of power flow. The proposed method has a feature which the objective function is minimized under unconstraints, as a result of the branch flow constraints are incorporated into the objective function. And also the DC load flow calculation is used to formulate this optimization of power now.

application/pdf, The aims of this paper are the simulation of volumetric efficiency and induction noise by using a simplified pulsating wave equation in the intake pipe of a single cylinder engine. As the result of calculations，absolute were not satisfactory but were good at quality. And so，we can estimate the optimum of the induction system by this calculation. And if we modify the thoretical equations a little，the addition of heat transfer from cylinder wall and friction loss of the pulsating wave， its value will become nealy equal to experiment.

application/pdf, This paper describes experimental investigations for characteristics of the flow about a flat plate immersed in a turbulent boundary layer. The non-dimensional mean velocities are compared with the wall proximity law and the velocity-defect law. The characteristics of the now about a flat plate -the distribution of velocity and pressure, and the flow patterns- are also discussed

application/pdf, In order to reduce the drag of a blaff body such as a circular cylinder and a blaff plate in an uniform flow, the authors have performed a series of investigations on the wake control .This paper reports the experimental results concerning the drag of a circular cylinder when the fluid is blown from a slit into its wake. The drag coefficient is found to decrease when the blowing velocity ratio is less than 0.84, while it increases when the blowing velocity ratio is larger than 0.84.

application/pdf, This study intends to perform successively the experimental investigations on the form drag of circular cylinders vertically placed in turbulent boundary layers. The main concern of the investigations is to relate the form drag of circular cylinders to the thickness of the boundary layer in which it is vertically mounted. In the present paper， correlations are obtained for the variation of the form drag of a single circular cylinder with a height of H in the flow field of pressure-gradient. The form drag coeffcient C^-_D)=D/q^-A defined with q，the average dynamic pressure in the boundary layer between y＝O and y＝H，for a single circular cylinder is found to be approximately 0.7?0.8，though it decreases slightly as δ/H increases