Takehiko Imai

Experimental studies on the surface areas of the Raschel knotless nettings.

The purpose of this study is to obtain the experimental equation concerning the surface area of the Reschel knotless netting, as a basic study for the fluid dynamical resistance, when the netting piece is set strictly parallel or almost parallel to the flow direction. The experimental equations are derived from the measurements of six paraffin models of the Raschel knotless nettings. 1) From the measured values of the perimeter of the section on the joint portion of the paraffin model. The experimental equation of the surface area of joint portion is derived as follows:- AK=12.20d2 2) From the measured values of the perimeter on the leg portion and the length of the joint portion, the experimental equation of the surface area of leg portion is derived as follows:- AL=6.14dl-17.75d2 3) From these results, the surface area of the Raschel knotless netting with the i×j meshes can be expressed in the following equation:- A=2ij(6.14l-5.55d)d+12.20(i+j)d2 A: Surface area of a Reschel knotless netting AK: Surface area of joint portion AL: Surface area of a leg portion f: Length of a joint portion Δf: Interval of the section on the joint portion i: Mesh numbers on the twinewise direction j: Mesh numbers on the normal direction l: Leg length PKm: Perimeter of joint portion on the mth section PL: Perimeter of a leg portion