Pipe Transportation of Minced Fish Paste

A pipe system was designed wherein minced fish paste was forced from the wide portion of a pipe to the narrow portion by an air cylinder, and extruded from the narrow portion. Pressure losses of minced fish paste in the narrow portion were transmitted through a transducer rod, and determined by two strain gages. The data for volumetric flow rate as a function of pressure loss were simulated by the power‐law flow model equation with yield stress, and fitted well to the equation. It was concluded from agreement of rheological constants that pressure loss was proportional to pipe length. However, some disagreements of rheological constants appeared when the ratio of pipe length to pipe inside diameter was decreased. This result was explained by the assumption that the entrance effect would become more pronounced. Contrary to expectation from the data of pure water through the pipe bend, pressure losses of minced fish paste through the pipe bend were not so large. This fact might be related to the Bingham plastic nature of minced fish paste. In pipe transportation of minced fish paste, shear‐thinning behavior was not found at a constant shear rate. While shear stress of minced fish paste ranged from 21000–29000 dyne cm −2 , shear rate ranged roughly from 20–240 set −1 . Flow behavior index was around 0.90 and the flow curve was almost a straight line. Yield stress was around 20000 dyne cm −2 , and about two‐thirds the total stress required for the flow at 240 set −1 .