AN EXPERIMENTAL STUDY OF THE BLOWROOM MACHINERY

(Part 7) OPENING ACTION

Abstract

It is well known that the performance of cotton opening is tested by handling method, but it is dificult to compare the result due to personal difference of operators and machinery used. For the efficient opening of cotton it is desirable that compressed materials are broken into small portions and loosend as much as possible with the minimum mechanical treatment. In order to know the fundamental action of opening, the specific weight of cotton tuft is measured at each process of the treatment. But as the above method is more trouble some, the author has measured the coefficient of air flow resistance of cotton in packed cylinder, and found the coefficient is usually better than the compressibility of cotton tuft to indicate the opening effect of blowroom machinery.
The formula of air flow resistance of packed cotton is as follows where P_d: air flow resistanece, K_d: coefficient of resistace, μ_f: air flow velocity, μ_f; viscosity of air, d: size of cotton tuft, H: packed height, γ_f: specific weight of air, γ_ds: density of packed cotton, g: gravity constant.
The opening action of each machinery by the ratio of specific weight of cotton and coefficient of air flow resistance were about 1.1_??_1.2, for different type of machines.