Impact Force by Transient Liquid Slug Flowing Out of Horizontal Pipes （1st Report, Experimental Study）

An impact force of a transient liquid slug was measured in air-water horizontal two-phase Flow system. The time response of the impact force was characterized by the initial impact force, maximum force, acting period of force and mean effective force which were discussed with reference to the volumetric liquid and gas fluxes and also to the Flow characteristics of the transient slug Flow in horizontal pipes

Impact Force by Transient Liquid Slug Flowing Out of Horizontal Pipes (2nd Report, TheoreticaI Study)

A transient liquid slug flow was analysed on the basis of the scooping model and by applying equations of integral balance of mass and momentum for an arbitrary geometrical volume closed by moving surfaces through which liquid Flowed in and out. The analytical results agreed well with the experimental results of the Flow characteristics and impact force of the transient liquid slug. The dynamic behavior of the impact force was discussed with reference to the analytical results of the dynamic behavior of the flow

Enhancement of Heat Transfer by Sinusoidal Oscillation of Fluid : Transient Behavior of a Dream Pipe

Experimental and analytical studies were carried out to investigate the heat transfer performance in a so-called dream pipe where the heat transfer in liquid was enhanced by sinusoidal oscillation. The heat transfer process in the dream pipe was formulated using a simplified lumped-parameter model, and the effective thermal diffusivity was obtained analytically. The effective thermal diffusivity increased with increasing frequency and amplitude of the oscillation. The numerical simulation of heat transfer agreed with that of the experiment, and thus, the applicability of the presented model to the estimation of the transient behavior of the dream pipe was verified

Behavior of a Large Bubble in a Horizontal Channel : 2nd Report, Large Bubble Penetrating into Running Liquid

The behavior of a large bubble penetrating into running liquid in a horizontal pipe has been studied experimentally. The flow regime of the large bubble is classified into the following three regimes : a steadily moving bubble regime, a transition regime and a stationary bubble regime. In the steadily moving bubble regime, the large bubble penetrates at constant velocity and the shape of the bubble nose does not change along the pipe. An analysis of the behavior of the large bubble has been carried out and the equation which gives the velocity of the large bubble in the steadily moving bubble regime is presented

Flow Characteristics of a Large Gas Bubble in Horizontal Channels : 1st Report, Flow Characteristics in Stationary Liquid

水平流路内に充満された静止液体が流路の一端開放により重力の作用を受けて流路外へ流出し始め,その代わりに気体が大気ほうとなって流路内に侵入する場合の流動現象を論じた.このような流動現象,特に大気ほう形状と大気ほう周囲の液体流速分布はポテンシャル流理論およびナビエ・ストークスの運動方程式の差分解法の一つであるSMACコードを用いた数値実験により十分に表されることがわかった