Papers by Keyword: Capillary

Abstract: The paper addresses the issues of subjective and instrumental quality assessment of flaw detection materials by Sherwin, Bycotest, Spotcheck, Chemetall and R-test penetrant materials using non-metallic test panels and software code.

Abstract: The paper considers the mathematical model of liquid motion in straight-line capillaries. The proposed mathematical model shows the liquid motion in slit-like capillaries, with regard to the density, viscosity and surface tension of liquids, the capillary size, and the angle of capillary inclination to the horizontal. The modeling results are proved by full-scale experiments.

Abstract: Nondestructive penetrant testing is effective, and in some cases, it is the only possible method of accidents prevention at high-risk sites. But in nowadays liquid-filled discontinuity model has not been adequately studied. Hydrodynamics in the open-end capillaries characterize the flow of liquids using the methods of leak detection. To detect surface discontinuities that are capillary, capillary flaw detection methods are used. Until now, the theoretical relation l = l (t) has not been find out. This relation makes it possible to calculate the absorption kinetics in any capillary at all its stages, which would coincide with experimental data with high accuracy. The studies show that the time of filling the capillaries by liquid is usually higher than the theoretically predicted one. Therefore, revealing the regularities of filling capillaries with liquids to the maximum depth and the duration of filling the capillary with liquid by a given depth is an actual task. The authors suggest a model for determining the velocity of fluid in dead-end and open-end and through capillaries, which take into account the fractal topology of the surface.

Abstract: Rising damp is one of construction’s major problems associated with use of porous materials in this industry. This mechanism has a massive influence on the degradation of historical buildings since they were built in a time when construction technologies made no effort to prevent this kind of pathologies. The rising damp by itself can reduce the aesthetical value of the building and, when combined with the existence of soluble salts in the building and in the ground water can even lead to material decomposition and compromise the structural performance of the building. This happens due to the migration of the salt ions dissolved in water into the porous network of the building’s walls where they remain and crystalize after water evaporates, dealing great pressures against the pore walls and eventually resulting in their fracture after many cycles of crystallization/dissolution.The experimental work intended to study the effect of two different saturated solutions of sodium sulphate and potassium chloride in the capillary absorption curves obtained through the partial immersion of red brick samples. In the end of this paper there will be a macroscopic evaluation of the sample’s crystallized top surface, obtained after a partial drying period. The results revealed significant differences in the capillary coefficients obtained when samples were tested with salt solutions.

Abstract: SAGD dynamic temperature and pressure monitoring technology can be used to detect multi-point temperature and pressure in production well, determine liquid state, accurately identify the movement direction of steam and breakthrough position so that it can effectively guide SAGD production and reduce operation costs, thereby significantly improve heavy oil recovery.

Abstract: Through the comparative study of solar capillary low-temperature hot water radiant heating system with air source heat pump system has found that solar energy heat collecting efficiency has a great relationship with the collector temperature for the given system. To reduce the temperature of solar heat collector circulating water can greatly improve the heat collecting efficiency of the heat collector .With the increase of temperature of the water in the heat collector, heat collecting efficiency decrease rate changes linearly. Increasing water storage can improve the heat collecting efficiency, for this heat collecting system, the optimum collector temperature is 32 °C. In this study, COP reached 5 when the low temperature solar hot water capillary system mode is being used, and this result is nearly 5 times higher than that of the air source heat pump mode . Using the low temperature solar water heating capillary system, 27.35 kwh / (m² ·heating season) of electricity can be saved compared with the amount of electricity consumed by air source heat pump. According to the price of current Beijing city , the estimated period of investment payback is 4.8 years .

Abstract: This paper introduces the advantages of capillary roof radiant heating system, by using finite element numerical method, the indoor temperature distribution of capillary radiant roof and underfloor supply air composite system is simulated, using the theory of exergy to analysis the energy saving of the system, the result proves that the system can well satisfy indoor comfort requirements, and compared with the floor radiation heating system can saving energy 65.8%, has great research value.

Abstract: Multi-function and all-electric rheometer (MAR) was designed by the authors to study the nonlinear viscoelasticity of polymer melts at high shear rate. It is important to design suitable size of capillary and barrel because it is the calculation basis for some other important parts and determines the shear rate range of MAR. Considering the shear rate range, the entrance pressure correction and the wall slip correction, the length and diameter of capillary and barrel of MAR were designed through particular analysis and precise calculation.

Abstract: A fluid dynamics in a micro channel for analytical chemistry and different aspects of this type of flow for specific application has remained a long-acting problem in the last two decades considering its numerus applications in various fields, thus, Surface tension and wall adhesive forces are often used to transport fluid through micro channels in Micro Electromechanical system devices or to measure the transport and position of small amounts of fluid using micropipettes. Here we took the advantages of wall adhesion and surface tension at the air/fluid interface, fluid rises through the channel and study also calculate the velocity, pressure and shape and position of the fluid surface, the model consist of a capillary channel of radius 50μm and a chamber. The study demonstrated that the fluid freely flown into the chamber 2mm/s without using any external mechanism.

Abstract: Radiation capillary used as air conditioning terminal lower the demand of heating water temperature. In additional, solar collectors could also supply amount of low grade energy for heating. Meanwhile, solar is a kind of renewable, sustainable and environment friendly energy. It will save a massive of conventional energy if make full use of solar for heating. In this paper, an experimental system made of solar collector, capillary network and pump was built up and tested. According to thermal load of experimental room, both solar collector area and capillary network area are calculated, and circulating water temperature was analyzed in detail. A summary is given about characteristics of heat storage and release of solar collector, indoor air temperature varying and amount of energy saving. The key factors affect efficiency of collector includes water volume, water temperature in tanker and indoor air temperature. The results show that the solar system can well meet the heating demand and the effect of energy saving is very significant compared to common heating system.