Volume 5, Issue 8, 01 August 1934
Index of content:
5(1934); http://dx.doi.org/10.1063/1.1745251View Description Hide Description
The viscosities of undercooled liquid glucose have been extensively studied by three very different methods. Between 145° and 80° about eighty determinations have been made by the falling sphere method; between 80° and 32° seventy‐five determinations have been carried out by a concentric cylinder method; and between 34° and 22° thirty samples have been measured by a cylinder torsion method. A series of ``best values,'' ranging from 5.6 poises at 145° to 9.1(10)13 poises at 22°C, have been tabulated from these results. They represent ``true'' viscosities and not plasticities. That the viscosities of the glucose depend very much upon the history of the sample and its mode of preparation has been shown by several experiments. From a consideration of the variation of the viscosity with the reciprocal of the absolute temperature some ``disorientation'' energy values have been derived. These are much larger than the formal heat of fusion of glucose and indicate considerable association.
5(1934); http://dx.doi.org/10.1063/1.1745253View Description Hide Description
A critical review and summary are given of some of the rheological aspects of the production and transportation of petroleum. It is shown how the proper flow characteristics of the colloidal dispersions known as drilling fluids may be controlled by chemico‐physical methods, and the importance of these characteristics in the technique of drilling is analyzed. The laws of flow of gas‐oil mixtures through porous media are approached by a study of the permeability factor of such media, and applied to the problems of ultimate production, production rate, effective drainage area, etc., of petroleum‐producing horizons. The flow of gas‐liquid mixtures through pipes is discussed from the standpoint of bringing oil to the surface from the reservoir. Pipeline flow of oil is discussed with particular reference to cold weather flow for oils that exhibit thixotropic properties because of a heavy content of wax. Unsolved problems in these various fields of the rheology of petroleum production are pointed out.
5(1934); http://dx.doi.org/10.1063/1.1745254View Description Hide Description
Samples of rosin, abietic acid and pitch may be made to flow at temperatures as low as 20°C at low pressures and conveniently short periods of time, sufficient for fluidity determinations. Such a method as this one was devised in the hope of finding a much better control instrument for such materials. No evidence of plasticity was observed. The fluidity was found to be independent of the dimensions of the apparatus used. In the pressure range from 130 to 1800 g per cm2 no effect of change of pressure upon the fluidity was detected. A study of the effect of changes in pressure upon the flow of plastic materials is now being made.
5(1934); http://dx.doi.org/10.1063/1.1745255View Description Hide Description