CC BY
12
UDC 665.6:532.135:532.137
R. A. Ilyasov, Ch. Abakis, T. Karapantsios, V. F. Nikolaev
THE FACTORS INFLUENCING THE DROPS FLOWING ON THE INCLINED METAL PANEL
Ключевые слова: реология, капельная склон-реометрия, масла, динамическая вязкость, краевой угол смачивания, напряжения сдвига, динамическое поверхностное натяжение, статическое поверхностное натяжение.
Были проведены исследования, чтобы определить факторы, влияющие на текучесть капли по наклонной плоскости установки Депар-021. Факторы, влияющие на текучесть, а именно, краевой угол смачивания, динамическая вязкость, поверхностное натяжение были исследованы. Было проведено измерение краевого угла на поверхности канала наклонной плоскости Депар-021.
Keywords: rheology, drop inclined plane rheometry, oil, dynamic viscosity, contact angle, shear stress, dynamic surface tension, static
surface tension.
Research had been conducted to identify factors affecting the flow over a drop inclined plane rheometer Depar-021. Factors influencing the fluidity, namely, contact angle, dynamic viscosity, surface tension were investigated. It was conducted to measure the contact angle on the channel surface of the inclined plane rheometer.
Introduction
Viscosity is one of the important properties of fluids. Knowledge of viscosity is necessary in the development of processes and equipment, tribotechnology in chemmotology and in several other areas of technology and science. Viscosity or internal friction is related with transport phenomena and characterizes the properties of the fluid body for providing resistance to the movement of one relative to the other parts [1].
Intention practice:
• the study of the rheological properties of engine oil brand 10 W-40
• the study the principle of operation Rheometer (Physica MCR301)
• the experiment with Rheometer (Physica MCR 301) on the shear stress, dynamic viscosity of engine oil brand 10 W-40
• the study of the operation principle for tensiometer LAUDA TVT 2
• the experiment with LAUDA TVT 2 for static surface tension of engine oil brand 10 W-40
• the study of the operation principle for tensiometer LAUDA TE-2
• the experiment with LAUDA TE-2 for static surface tension of the engine oil brand 10 W-40
• the study of the operation principle for tensiometer SINTERFACE PAT1
• the experiment with SINTERFACE PAT1 for measurement of the contact angle of the engine oil brand 10 W-40 to dural surface
• the analysis of the data.
Experimental Techniques
In the first week of practice, intention was identified. In the second week, we studied the software and operation of the rheometer Physica MCR301, and measurements were made to determine the shear stress and dynamic viscosity of engine oil brand 10 W-40 at temperatures of 25°C and 35°C ( Table 1).
Table 1 - Engine oil brand 10W-40 shear stress, dynamic viscosity
T, °C Shear stress, Pa Dynamic viscosity, Pa^s
25 4.34 0.173
35 2.58 0.103
In our experiments, we tried to determine the effect of surface tension on the surface of duralumin. Panel installation Depart-021 is made of duralumin (fig. 1) [2-6].
Fig. 1 - Drop inclined plane rheometer Depar-021
In the first stage of the research the principles of the tensiometer LAUDA TVT 2 were studied. It is based on the measurement of drop weight or drop volume technique. LAUDA TVT 2 consists of a measurement desk and a control unit. The core of the electronic component is a microprocessor that controls the discharge speed, the counting of the encoder pulses, and the communications.
Product Features: • Characterization of the dynamic behavior of surfactant molecules on the surface within seconds or hours.
The second stage - the reading of the tensiometer LAUDA TVT 2 (dynamic surface tension of engine oil brand 10 W-40) and comparison with literature data (fig. 2).
10W40 (1) 10W40 (2)
♦ ♦
20
40
60
t, s
80
100 120
Fig. 2 - Dynamic surface tension of engine oil brand 10 W-40, measured with Drop volume technique (TVT 2, Lauda)
Continuation of research in this area was studying the principle of operation of the tensiometer LAUDA TE2. This instrument is used for the measurement of static surface tension by the du Nouy ring method and Wilhelmy plate method, where surface tension is calculated as a function of meniscus weight. We carried out measurements using Wilhelmy plate method. Ir-Pt (90/10) plate (perimeter 40 mm) interacts with the surface of the liquid, wherein the liquid wets the plate along a vertical path. The plate is with its lower edge at the zero level (at the level of the liquid surface), with contact angle equals zero, during the entire measurement. In this case there is no need to introduce a correction to the weight force of the liquid under the plate, as in the method of the ring.
Tensiometer readings LAUDA TE-2 on the static surface tension of motor oil brand 10 W-40 by the method of Wilhelmy plate (Table 2).
Table 2 - Static surface tension of engine oil brand 10W-40 by the method of Wilhelmy plate, compared with literature value
T, °C Surface tension, mN/m
Engine oil 10W-40 25 29.71
Petrol 25 26
engine oil brand 10 W-40 contact angle were carried out on the tensiometer SINTERFACE PAT1.
Product Features
This tool allows you to measure a variety of physical properties:
• the surface tension of the liquid
• static and dynamic contact angle in accordance with the method of pendant/sessile drop
• surface rheological studies to measure dilatational elasticity and viscosity
• measuring capillary pressure liquid / liquid systems
• time dependence of all measured values
• Online temperature control
• area or volume may be constant during the measurement
• the duration of the measurements of 0.1 seconds to a few days.
There is a problem in determining the contact angle on the tensiometer SINTERFACE PAT1, since this unit is able to determine the contact angle of the horizontal surface of the aluminum. In our studies, we had to measure the contact angle of the surface of the channel, because the droplet deposited in the channel and not on a horizontal surface of duralumin. In this regard, it was decided to carry out macro- and micro-photography using a professional camera CANON EOS 350. The results of this survey were not justified.
To improve the quality of photos, it was decided to use additional lighting. However, this was only slightly improved the quality of photography and made it impossible to determine the contact angle on the channel plate made of aluminum.
At the end, we used SINTERFACE PAT1's camera. A KDS infusion pump (Ugo Basile Srl, Italy) with a Hamilton syringe were used for pouring of engine oil brand 10 W-40 on dural's channel surface.
Engine oil's total volume for the measurement of contact angle was 0.2 ml. Pumping rate was 10 ml/h. Engine oil brand 10 W-40, dural and room temperature were thermostated at 25°C. Temperature was checked with a thermocouple. A picture from was taken every 0.02 ml up to 0.2 ml for the measurement of advancing and receding contact angle. As a result, pictures of good quality were taken (fig.3).
0
Advantages of the ring Du Nouy
• A lot of data in the literature;
• Load up on the ring, thus higher accuracy;
• Some substances, such as cationic surfactants exhibit low wettability of the plate;
Advantages of the Wilhelmy plate
• Does not require the introduction of amendments;
• The measurement is performed only by touch,
without the pressure and phase mixing.
The third stage of the study was determination of effect of the contact angle on the properties for the drop on the surface of the installation Depart-021. It was tasked with figuring out how the contact angle affects the fluidity of the drop on the surface of aluminum. Measurements of
Fig. 3 - Pictures of oil on dural's channel surface taken by using SINTERFACE PAT1's camera with the KDS infusion pump and a Hamilton syringe
Contact angle values of engine oil brand 10 W-40 on the surface of duralumin can be seen to (fig. 4.
Fig. 4 - Diagram of the advancing and receding contact angle
Conclusion
Research had been conducted the factors affecting on the fluidity of fluids on the duralumin sloping surface.
It was also found that the surfactants in engine oils have
little effect on the fluidity at duralumin sloping surface.
We propose an entirely new method of measuring the
contact angle on a rough surface.
Literature References
1 Р.А. Ильясов, В.Ф. Николаев, Р.Б. Султанова. Научная дискуссия: вопросы технических наук материалы XII международной научно-практической конференции (Москва, Россия 25 июля 2013 г.) Москва, 2013. 80-85 с.
2 V.F. Nikolaev, A.V. Egorov, I.V. Nikolaev, R.B. Sultanova, Petrol. Sci. Technol., 31, 3, 276-283 (2013)
3 В.Ф. Николаев, А.В. Егоров, М.А. Васин, И.В. Николаев// Завод. лабор. Диагн. материалов, 78, 10, 31-35 (2012)
4 В.Ф. Николаев Экспресс-методы тестирования композиционных продуктов нефтепромысловой химии и моторных топлив. Изд. КНИТУ, Казань, 2012. 124 с.
5 В.Ф. Николаев, А.В. Яшина, Р.Б. Султанова // Вестн. Казан. технол. ун-та. 16, 24, 98-101 (2013)
6 А.В. Егоров, М.А. Васин, В.Ф. Николаев // Вестн. Казан. технол. ун-та, 14, 11, 85-87(2011).
© R. A. Ilyasov - master Kazan national research technological university, rustam.ilyasov@mail.ru; Kazan; Ch. Abakis - postgraduate Aristotle University of Thessaloniki, Greece; Th. Karapantsios - professor Aristotle University of Thessaloniki, Greece, karapant@chem.auth.gr; V.F. Nikolaev - professor of KNRTU, nikolaev@iopc.ru.
© Р. А. Ильясов - магистр КНИТУ, rustam.ilyasov@mail.ru; Ch. Abakis -асп., Университет Аристотеля, Салоники, Греция; Ch. Abakis - проф. Университета Аристотеля, Салоники, Греция, karapant@chem.auth.gr; В. Ф. Николаев - д-р хим. наук, ст. науч. сотр. лаб. химии и геохимии нефти, Институт органической и физической химии им А.Е. Арбузова КазНЦ РАН (ИОФХ), проф. каф. технологии основного органического и нефтехимического синтеза КНИТУ, nikolaev@iopc.ru.
