Title: The possibility of using the hypothesis of quasistationarit y for a pulsat- ing laminar flow of viscous fluid in a capillary has been tested experi- mentally. It is shown that for the given parameters the use of this hypothesis leads to a satisfactory agreement between theory and experiment.
Abstract:fluctuations of the pressure in the case of fluid flowing in a tube of small diameter a capillary. To investigate the pulsating laminar flow of a viscous fluid in a capillary, we arranged a special ex...fluctuations of the pressure in the case of fluid flowing in a tube of small diameter a capillary. To investigate the pulsating laminar flow of a viscous fluid in a capillary, we arranged a special experiment. This experiment, which is shown schematically in Fig. i, used a screw pump I, a feedpipe, a straight measuring section, a vibrator of valve type 2 with independent drive producing the pressure fluctuations, an outflow line, a container 3, and a flow meter 4. The measuring section had length 400 mm and diameter 2.3 or 4 mm. Along its length there were three sensors (SI, $2, $3) of the type TDD, the distance between the sensors being 200 mm. The readings of the sensors were recorded by means of a light-beam oscillograph, and the sensors were calibrated by means of a screw press. In the experiment, we recorded the readings of the sensors SI, $2, $3~ the frequency of the pressure fluctuations produced by the vibrator, the mean flow rate, and the temperature of the working fluid. This last was an aqueous solution of glycerine. The viscosity of this solution was determined as a function of the temperature by means of an Ostwald--Pinkevich viscosimeter. The maximal value of the Reynolds number, calculated using the mean flow rate, did not exceed 20, so that the flow of the fluid in the investigated regimes was laminar. As boundary conditions for Eqs. (i) we can use the values of the fluctuations of the pressure at the ends of the tube, i.e., the fluctuations of the pressure measured by the sensors S 1 and S 3. Thus, the boundary conditions can be written in the form x=O, p(O, t)=~(t); x=l, p(l, t)=~(t) (2) Here, ~(t) and ~(t) are known periodic functions of the time, and 2 is the length of the tube. Knowing the solution of Eqs. (1) for the boundary conditions (2), we can calculate p(x, t) at the section at which the sensor S 2 is situated, i.e., for x = 2/2. The analysis of our experiment consisted of comparing the obtained calculated values of the pressure with the experimental values measured, by S 2.Read More
Publication Year: 1982
Publication Date: 1982-01-01
Language: en
Type: article
Access and Citation
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot