目的 T形合流路における高分子溶液の流れについて, レーザドップラ流速計 (LDV) を用いて詳細な流速測定を行い, 合流部付近の速度分布から粘弾性流体の流れの特徴をニュートン流体と比較して検討する.結果 流速測定から粘弾性流れの特徴である凸状角部上流側の循環2次流れの存在が確かめられた.循環2次流れが生じ始めると合流部付近の流れ挙動は, 粘弾性流体とニュートン流体との間に顕著な違いがみられた.さらに流速が増加すると流速分布は一定の形に収斂するようであるが, 合流部付近に流速の周期的な変動が測定された.

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衣料用布地の熱水分伝達特性を測定する新しい装置を開発したので, いくつかの応用を含めて報告する.この装置の基本的な機能はつぎのとおりである.
1) 布の熱吸収特性の測定;この吸収は薄い1枚の銅板に熱を貯え, これを布の表面に接触させることによって開始する.この吸収に伴う熱流信号をローパスフィルタに通すと熱流量にはピーク値が約0.2sec後に現われる.このピーク値をqmaxと定義し布の温冷感触感に関係する量として記録する.この過渡法を用いて布の熱伝導率, 熱拡散率も測定できる.
2) 定常法による布の熱伝導率の高速測定;平行板方式の測定を行うが, 平行板の1枚は薄いアルミニウム板でその温度を精密に制御し, かつ高速応答性を持たせている.2℃ の設定温度差を階段状に加えたときの応答は10secである.この高速性は布の状態に乱れを与えることなしに熱伝導率を測定することができる.例えば布のリゲインを変化させない.
3) 布の保温性の各種様式による測定;布からの空中への熱放散, すなわち保温性の測定において, 熱損失を連続的に測定することができる.通常の保温性の測定―― ここではドライ法と呼んでいる―― は2, 3min以内に完了できる.応用測定の一つとして, 皮膚法を紹介する.水を多量に含んだ紙を熱板上に置き, 模疑皮膚とする.この上に布を直接, またはいくらかのすき間を作っておき, 測定する.この方法での熱損失測定から布の熱・水分伝達特性についての多くの情報を得ることができる.例えば羊毛の夏スーツ地はポリエステルのそれより涼しいなど明瞭に示される.このようないくつかの結果を報告する.

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The effects of some factors on the knitting defects due to knots in the plain-weft knitting were studied experimentally.
The results obtained were as follows
(1) The knitting defects due to knots were almost knitting holes which were caused by end breakages in the plain-weft knitting zone. The end breakage occured at the point of take-down side at a short distance from the knot.
(2) As each of knitting factors such as the depth of stitch draw, the input yarn tension, the takedown weight, the machine gauge, the coefficient of friction between yarn and needle and the machine speed were increased, the end breakage rate incresed. But the increase of the cam angle decreased the end breakage rate.

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This experiment is carried out on the model of the phenomenon which takes place when a cuprammo nium linings on the piles of a rayon velvet is pressed down by the presser foot during the sewing operation. The results obtained are as follows.
(1) Assuming that the lining on piles under pressure is shifted by the tips of the piles, the shift of the lining parallel to the horizontal plane are measured in the case of two kinds of toothbrushes, one of which has the same height of piles and the other has two height levels of piles. In the latter case, the shift of the lining finally becomes greater than the height of the longer piles.
(2) The shift of the lining on the velvet pressed by a plate can approximately be given by the shift of the latter case in (1).
(3) All the piles of velvet lean in a certain limited direction by pressing and the coefficient of static friction of the velvet is minimum in the pile direction and is maximum in the opposite direction.
(4) With increasing the pressure, the coefficient of static friction of the velvet in the pile direction decreases, but the one in the opposite direction increases with increasing the pressure beyond the critical value.
As above mentioned, the lining on the piles of the velvet is shifted into a pile direction by tips of piles when the pressure of a plate is applied. If the pressure exceeds the critical value, the larger difference in the coefficient of static friction is recognized between the pile direction and the opposite direction. Therefore, it is almost impossible to prevent the shift of the lining by hand. So, this phenomenon is referred to as “Green Bristle Glass (Setaria Viridis) Effect” by the authors.

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As the FRP is superior in the corrosion resistance and is more inexpensive in material cost than corrosion resistant metallics, recently it is widely used for large diameter piping material.
To join the FRP piping of large diameter, a double lap joint is generally used, in which the secondary adhesion is applied on both inner and outer surface. Until now it is empirically said that the de sign water velocity is 3m/s and critical water velocity is 6-10m/s with regard to the peeling off of the second adhesion part laminated inner face produced by water flow. But the piping for sewer and water-conveyance that has been used until now is flat with low water velocity and low water head. The process piping of large diameter is provided with bends, branches, pipes with head, control valves and heaters in the piping system. The pressure, velocity and temperature vary greatly in the pipe. Therefore, it is necessary to consider whether the values on the basis of former experiment are suitable for the process piping. The purpose of this report is to make clear the basis of the peeling off limit in the former experiences. In this report of part 1, the experiment of the peeling off by the water jet is shown. This experiment is concerned with the forming factor and selection of material, disregarding the secular deterioration of resin. In the next report (Part 2), the same experiment on the secular deterioration of resin will be shown. The mechanism of peeling off by water flow will also be considered. Further a new method of the second adhesion joint which will prevent the occurence of the peeling off will be proposed.

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