Fluid mechanics of viscous and non-Newtonian fluids is very much significant to many processes in the oil, chemical and food industries. For the purpose of mixing solid, liquid and gas streams, mechanically stirred tanks are widely used in industries. The performance of mixing affects the mixed product quality, rate of reaction of the reactor etc. It is well known that the viscosity of the fluid is the key factor of the flow behaviour of non-Newtonian fluid (Tanguy et al., 2006). The non-Newtonian fluid viscosity is closely related to the applied torque on the impeller. If viscosity of the non-Newtonian fluid is very high (flow index tends to zero), the required torque for achieving the satisfactory mixing becomes also very high and this leads to destruction of mixing system (Dular et al., 2006). Hence, the mixing of highly viscous non-Newtonian fluid is usually carried out at low Reynolds number in laminar or in early transition regime (Fuente et al., 1997). The previous research works in the last few decades also has confirmed that for the low viscous (flow index tends to 1.0) non-Newtonian fluid, the study of mixing is restricted to laminar and transition regimes (Metzner and Otto, 1957; Chavan and Ulbrecht, 1973; Thibault and Tanguy, 2002; Jahangiri, 2005; Szoplik and Karcz, 2008). Nouri & Whitelaw (1990) and Koutsakos & Nienow (1990) also have investigated the effect of non-Newtonian liquid properties on the mixing performance of stirring vessels. Fuente et al. (1997) has studied the mixing of ten different rheological complex fluids using helical ribbon and helical ribbon screw impellers. They have observed the inverse relation between the power consumption and pseudo plasticity. They also have reported that the power consum...
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...ent on the total solids concentrations. The turbulent flow mixing is modelled by employing the realizable k-ε model. The predicted power and flow numbers of an impeller were validated against the lab specifications. Wu (2011) has done CFD simulation of non-Newtonian fluids in a lab-scale anaerobic digestion tank with a pitched blade turbine (PBT) impeller in turbulent flow regime. Six different turbulence models are used but realizable k-ε and the standard k-ω models were found to be more suitable than the other turbulence models. Ameur and Bouzit (2012) have carried out a CFD simulation of a shear thinning fluid using curved-blade impellers in a cylindrical unbaffled vessel at laminar and transition regime. They have studied the effect of the impeller speed, the fluid rheology and the number of impeller blades on the induced flow patterns and the power consumption.
Fig. 2(A) shows the phase diagrams of IPM, water, and surfactant mixtures at the ratios of 60:40, 65:35, and 70:30 (v/v), respectively. Fig. 2(B) shows the phase diagrams of ethyl oleate, water, and surfactant mixtures at ratios of 90:10, 95:5 and 100:0, respectively. Filled circles mean self-emulsifying points, and black areas represent the self-emulsifying regions. In other area, the compositions showed inverted emulsion, gel-like form, or phase-separation. In general, when the oil content in the oil and surfactant mixtures is ≤30%, the condition of the mixtures changed from water-in-oil emulsion to a clear gel-like form and then to microemulsion. Otherwise, the dispersions showed phase separation, this result was similar to the results previously studied by Guo et al. [16]. Our finding showed that IPM + surfactant mixture (65:35, v/v) and ethyl oleate + surfactant mixture (90:10, v/v) showed the most self-emulsifying regions (Fig. 2). Overall, in contrast to IPM + surfactant mixture (65:35, v/v), ethyl oleate + surfactant mixture (90:10, v/v) showed finer emulsion in larger self-emulsifying range. These results indicate that ethyl oleate and Tween 80:Carbitol (90:10, v/v) were identified as the optimal oil
An emulsion is the forcing of substances that would not normally mix. In this experiment, multiple oil-in-water emulsions were performed. An oil-in-water emulsion is when there are little droplets of oil dispersed throughout water. The most common type of emulsion includes fats and water. A temporary emulsion was formed from this experiment. A temporary emulsion has to be shaken or mixed in some form to stay together (later on it will separate). This similar idea is used with salad dressings.
- Glaciers flow under the force of gravity as snow accumulates on the upper parts of the glacier and wants moves down slope.
The thermometer, containers, and iron ball were secured of any possible contaminants. The stopwatch was calibrated and checked to be correctly measuring the time in seconds and milliseconds, by comparison with other stopwatches. The thermometer was checked to be accurately measuring the temperature of lukewarm water, and was al...
For over two hundred centuries, mankind has wrestled with the problem of how to hit an object with another object. From the earliest days of the bow and arrow, to today's modern missile defense system, the need to achieve maximum accuracy and distance from a projectile has been critical to the survival of the human race. There are numerous of ways to solve the problem ranging from trial and error—as early man did—to advanced mathematics including trigonometry and calculus. (While the specific mathematical operations are beyond the scope of this work, we will briefly touch on the equations of motion and how they apply to projectile motion as the project progresses.)
The temperature dependence of viscosity can be very strong; for example, in motor oil, η can diminish ten-fold with only a 10% increase in the absolute temperature. Therefore, if temperature is not uniform but varies with position in a flow, one cannot obtain a single value for its viscosity. The other dependence of viscosity, on shear rate, is a non-Newtonian property of some fluids; this effect is called “shear thinning” if η diminishes with increasing γ.31 Shear thinning can be avoided in an experiment by applying a small shear stress, so that conditions are relatively close to
Introduction to Aerodynamics Aerodynamics is the study of the motion of fluids in the gas state and bodies in motion relative to the fluid/air. In other words, the study of aerodynamics is the study of fluid dynamics specifically relating to air or the gas state of matter. When an object travels through fluid/air there are two types of flow characteristics that happen, laminar and turbulent. Laminar flow is a smooth, steady flow over a smooth surface and it has little disturbance. Intuition would lead to the belief that this type of air flow would be desirable.
In practice, fluids experience friction against surface area. The friction generated corresponds to an energy transformation from kinetic → heat and results in a –ΔP over the length of the fluid flow. We denote this energy loss between point 1 and point 2 as ΔPfriction and account for it experimentally, depending on whether the flow is described as laminar or turbulent by the Reynolds number. Reynolds number is determined by the ratio of inertia forces to viscous forces.
Viscosity is the tendency of a fluid to resist flow and can be thought of as the internal friction of a fluid. Microscopically, viscosity is related to molecular diffusion and depends on the interactions between molecules or, in complex fluids, larger-scale flow units. The opposite of the viscosity is the fluidity which measures the mobility for fluid layers (Secco et al, 2013). Viscosity is affected by the temperature and composition of the fluid and, for compressible fluid, also by pressure (Serway et al, 2012).
The purpose of this experiment is to examine the performance and characteristics of a centrifugal pump, its motor, and the corresponding piping system, used to pump an ethylene glycol solution. The pump used in this experiment has a performance curve based on water, so pump performance curves, as well as motor performance curves, will be developed over a wide range of flow rates to determine the effect that the liquid viscosity and density have on the performance of this pump. Also, the pressure drop of the piping system will be examined to determine the extent of, if any, fouling in the pipes.
The study of physics and fluid dynamics in swimming has been a field of increasing interest for study in the past few decades among swimming coaches and enthusiasts. Despite the long history of research, the understanding of how to move the human body effectively through the water is still in its infancy. Competitive swimmers and their coaches of all levels are constantly striving for ways to improve their stroke technique and overall performance. The research and performances of today's swimmers are continuously disproving the beliefs of the past. Like in all sports, a better understanding of physics is enabling the world class swimmers to accomplish times never before thought possible. This was displayed on the grandest of scales in the 2000 Olympics when Ian Thorpe, Inge De Bruijn, Pieter Van Den Hoogenband and a number of other swimmers broke a total of twelve world records and numerous Olympic and national records.
- the effect of Viscosity on liquid flow (turbulent/laminar) I have consulted my teachers for guidance and I have also looked very carefully into the "the Suggestions papers" which contain many possible investigations which have been done in the past. I opted to choose neither of them but many aspects I will be looking into in my investigation are similar to those in the papers.
Saravanamutto, H. I. H., Rogers, G. F. C., Cohen, H., & Straznicky, P. V. (2009). Gas turbine theory (6th ed.). London, UK: Prentice Hall.
It is interesting to note that the ongoing controversy concerning the so-called conflict between Wilhelm Gottfried Leibniz and Isaac Newton is one that does not bare much merit. Whether one came up with the concepts of calculus are insignificant since the outcome was that future generations benefited. However, the logic of their clash does bear merit.
... temperature of 112 0C also and a pressure 2.5 bar. Cooling water is used to condense the vapor exiting column. Remaining methane and hydrogen are separated in reflux drum where the vapor stream is combined with other gases streams. The overhead of first and second separator are combined to form fuel gas. The liquid stream exiting in the bottoms of the reflux drum is pumped at pressure of 3.3 bar for discharging pressure. The pump stream is separated in two streams. One stream is to feed to tray one of the column and the other one stream is cooled down to 38 0C in heat exchanger. Then, the cooled product stream is sent to storage.