Screw Design and Newtonian Fluid Flow

Abstract

A series of screws were evaluated with regard to their ability to convey two Newtonian fluids with nominal viscosity of 1000 Pa* s at room temperature. Screws with helix angles of 7, 17, 30 and 45 degrees were constructed with a diameter of 50 mm. Screws at several of the angles also had three flight depths. The extruder-screw pump was constructed so that both the screw and barrel could be rotated independently. We will present the data for the screw rotation of 11 screws. The results strongly suggest that the pumping, volumetric output per revolution, of the screw and the barrel are the same regardless of the screw flight height which had a maximum value of about 0.8 thus leaving the core at only 0.2 the barrel diameter. Since pressure back flow is a function of the first power of the flight with and the cube of the flight height, the measured outputs had to be corrected for this in order to calculate the actual screw forwarding ability.

Nghiên Cứu Dòng Chảy Của Nhựa Nóng Chảy Trong Thiết Bị Đùn Trục Vít Đơn

“…Tiếp theo, Campbell G.A. và các cộng sự [6] nghiên cứu dòng chảy của nhựa nóng chảy trong một thiết bị đùn có đường kính trục vít D = 49,66 mm. Tuy phương trình của họ khá đơn giản nhưng tính ứng dụng không cao vì bản thân đường kính trục vít là một thông số đầu vào, và cần phải ước lượng / đo được lực kéo và phản lực tác dụng lên trục vít.…”

Development of A Filament Extruder Using Flow Theory with The Newtonian Fluid Assumption

“…Next, Campbell G.A. et al [6] studied the flow of molten plastic in an extruder with a screw diameter of 49.66 mm. Although their equation was simple, the applicability was not high because the screw diameter itself was an input parameter, and it was necessary to estimate/measure the drag force and the reaction impact on the screw.…”

The Effects of Screw Geometry on the Pumping Efficiency of Micro‐Screw Pump

“…On the other hand, the effects of screw geometry on extruder operational characteristics have been studied by Tsao et al (1978). Also, an experimental investigation of the interactions between screw helix angle and channel depth have been undertaken by Campbell et al (1997). Li and Hsieh (1996) have developed a new analytical solution of an isothermal, Newtonian flow in a single screw extruder with a finite channel and the actual boundary conditions encountered.…”