Degassing is widely used in the chemical, food, microbiological, and other industries. Degassing is performed by heating an aerated liquid while simultaneously stirring. Such a procedure has low efficiency, consumes much energy, and does not guarantee a high quality of degassing. Degassing in a centrifugal field in a thin-film liquid flow is an order of magnitude more efficient and provides the required quality of degassing. However, broad implementation of this process is constrained by the lack of deep theoretical studies and their based process design procedure.Let us consider degassing of a nonlinearly viscous liquid flowing over the heated inner surface of a tapered rotor in a special conical coordinate system ( l , ϕ , z ) ( Fig. 1). The aerated liquid is fed at constant volume flow rate q l to the center of a truncated tapered rotor rotating at constant angular velocity ω . When touching the horizontal part of the tapered rotor, the liquid is decelerated in the radial direction and accelerated in the tangential direction; i.e., a spatial boundary layer forms. At radius r , this layer reaches the film surface. Thus, there are three regions of the flow of the liquid fed to the center of the rotating rotor, namely, potential flow region 1 , spatial boundary layer region 2 , and thinfilm flow region 3 (Fig. 1). In region 3 , all of the liquid fed to the rotor is set in rotary motion and the integral continuity equation is valid. The size of the horizontal part of the tapered rotor is chosen so that r 0 ≥ r ; this prevents the rotor from flooding and ensures the thin-film liquid flow over the inner surface of the rotor at velocity components v l , v ϕ , and v z .In considering the degassing, we assume that the flow of the aerated liquid is laminar, waveless, and axisymmetric. It is supposed that the rise of gas bubbles to the liquid film surface and their penetration through the interface do not distort the flow pattern. The gravity, the surface tension, and the friction of the film against the gas medium can be ignored. We also assume that T w = const and ∂ T / ∂ z | z = h = 0. Since the maximal velocity of the relative motion of a babble and the liquid is vanishingly small in comparison with the volume-average aerated flow velocity, we use a quasi-homogeneous model of degassing. We also suppose that the physicomechanical properties of the gas in the quasi-homogeneous medium almost do not affect the rheological constants of the dispersion medium.Abstract -The flow of a nonlinearly viscous power-law liquid over the heated inner surface of a tapered rotor is considered. The form of a solution is found that enables one to reduce the complete partial differential equations of rheodynamics and convective heat transfer to a set of ordinary differential equations. The set is integrated numerically by the Runge-Kutta method using a procedure of reduction to a Cauchy problem by Newton's method. The velocity, temperature, and pressure fields in the liquid film are determined. Two steps of degassing are considered, namel...

An experimental study is made of the flow of solutions of cellulose nitrates in a stationary tube and a tube rotating about its own axis. Comparison of the results obtained from experimental and theoretical studies shows that they agree well with one another. Key words: non-Newtonian fluid, cellulose nitrate solutions, tube rotating about its own axis, experimental and theoretical studies.The non-Newtonian flow of a fluid in tubes rotating about their own axis was described mathematically in [1, 2] for two cases of the behavior of the medium near the solid boundary: attached flow and boundary-layer slip flow.Since it is difficult to determine the radial V r , tangential V ϕ , and axial V z velocities of such a flow experimentally, in order to confirm the adequacy of the mathematical model in describing the actual flow we designed and built an experimental unit that makes it possible to do the following: measure the pressure of the fluid on the wall of a tube rotating about its own axis at different angular velocities; maintain a constant angular velocity for the rotation of the tube or vary this parameter while measuring it and the rate of flow of the fluid.The unit (Fig. 1) includes a thin-walled tube 1 of corrosion-resistant steel with an inside diameter of 26 mm and a length of 1100 mm. To prevent vibration and deformation of the tube during its rotation, it was installed on three supports 2 and 3 and rotated inside long bearing assemblies that included two radial roller bearings.To measure the piezometric head of the fluid, plugs 6 with a thin elastic base (membrane) were inserted into bosses 4 welded to the tube every 260 mm of its length. The base of the plugs was 10 mm in diameter and ranged from 0.2 to 0.4 mm in thickness. Strain gages 5 were stuck to the inside surface of the plug. The gages sensed the elastic strains in the membrane as the medium flowed along the through portion of the tube. The gages had two terminals, each of which was secured to the clips of multichannel mercury current pickup 7. This arrangement made it possible to simultaneously transmit electrical signals from four rotating gages connected so as to form the bridge circuit of extensometer 8, which was powered from dc source 9.The output signal from the current pickups was sent to flat switch 10, which received an electrical signal from each of the four gages in succession for recording by millivoltmeter 11.To balance the bridge of the extensometer, a fifth, compensating gage was diagonally mounted on top of calibration beam 12 of calibration unit 13. The latter unit was connected to extensometer 8 through switch 11.The hydrodynamics of flow of anomalous fluids was studied inside a stationary tube (ω = 0) and a rotating tube. The speed of rotation of the rotating tube was measured with stroboscope 15 and was regulated with a speed box. The rate of flow of the medium was measured volumetrically with a graduated vessel.

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The pro-apoptotic effect of new 2-thioxo-4-thiazolidinone derivative Les-3331 on MCF-7 and MDA-MB-231 cell lines ..

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