抄録
When the setting between the top of the metallic or model wire and the plain plate and the depth from the top of wire to the bottom of groove are changed respectively, the friction factor λ of wire is obtained by measuring the drop in pressure at different values of velocities of the air in a given length of a very thin rectangular tube in the same manner as mentioned in the previous report.1)
From the relationships between the drop in pressure ΔP in a given length of the tube and the mean velocity of the air _??_ and those between λ and Re for laminor flow (Re<1000), the following results are obtained:
1) When the setting is changed, the drop in pressure at a mean velocity is maximum in the minimum setting between the top of wire and the plain plate.
2) When the depth from the top of wire to the bottom of groove is changed, the drop in pressure increases with decreasing the depth of groove even in the constant setting. Moreover, in the relation between λ and Re expressed as λ=K/Re, the higher value of K is obtained in case of the shallower groove.
From these results mentioned above, the effective carding action can be expected pneumatically between the plain plate and the metallic wire by minimizing the setting and by using the wire having the shallowest groove.
