Machines and Apparatuses of Chemical Plants. Machines and Apparatuses of Oil and Gas Industry
Reactor equipment designed for oil refining operates under complex conditions of thermal-cyclic loading and aggressive impact of the refined medium. Due to the periodicity of coke desired product obtainment, complex loading mainly affect the operation of reactors of the delayed coker units [1,2]. Appearance of defects of various kind accompanies the operation of reactors practically from the very beginning of its application [1-4, 6].
The most promising method of evaluating the limit state is the calculation-experimental approach to determine the dependency of changes of mechanical characteristics of the material in time [37, 39]. Such an approach would more appropriately at the design stage to calculate risks in the operation of hazardous production facilities [29, 30]. Thus, a review of studies devoted to the question of reliability of the reactor equipment, allows making a conclusion about the possibility of developing a comprehensive methodology to assess cumulative damage, limit state structural material and operational risks at the design stage and exploitation.
This article is devoted to the study of fluid flow in the shell side of shell-and-tube heat exchanger (STHE) and the assessment of the influence of geometric parameters on the thermal-hydraulic characteristics.
More intense heat transfer can be achieved by increasing the fluid velocity, but at the same time, it leads to a large increase in pressure drop that reduces the efficiency of heat transfer and increase operating costs.
Transfer of certain thermal energy at lower fluid velocity require more heat exchange surface that will increase the cost of the heat exchanger.
Thus, it is important to find ways to improve the thermal efficiency of heat exchange equipment by selecting optimal geometric parameters providing the most efficient heat transfer.
The efficiency of heat transfer in STHE can be increased by restricting dead zones formed near the cross baffles because of which the pressure drop is increased without a corresponding increase in heat transfer coefficient.
The size of the dead zone depends on the baffle spacing and the baffle cut. Thus, the optimal ratio of parameters will reduce pressure drop.
This article presents the results of investigations of the influence of baffle spacing and baffle cut on the size of dead zone formed near the cross baffles using numerical simulation methods. It is showed the structure of an additional baffle plate which can be used to reduce the dead zone and smoother flow distribution over the cross section.
Results of modeling low frequency oscillation superposition on primitive features of 1600 mm diameter vessel for vibration treatment of welding joints technology developmentare shown in this work.
Currently, there is a sufficient number of works in which indicated a positive effect of vibrations imposed in the process of weldingand after it. Thus, as a rule, not the place for the installation of the vibration device. Especially in those cases when local vibration treatment of constructions with low rigidityis proceeded.
In this work, with using of finite element modeling methods was determined that in the process of a local input vibrations from two sources operating in the same phase at a frequency of 150 Hz and amplitude of 1 mm change brewed seam area in the weld zone does not occur internally oscillation amplitude greater than 1 mm. Thus, it can be assumed that during welding of the body vibration machine with a local treatment at the frequency of 150 Hz and an amplitude of 1 mm will not occur resonant phenomena, adversely affect the properties of the weld metal. This will expand the use of technology in the processing of the vibration welding process the cabinet shell type.
Also natural vibration frequencyof the details the cabinet diameter of 1600 mm, mounted on castors, of brewed seam area for applications is obtained for next cases: welding the shells together, welding first and second bottom of the cylindrical housing. Determined that natural frequency of the body parts, depending on the brewedthe seam area is almost constant and the 1st to the 3rd mode of vibration is less than 90 Hz.
During the operation of electrical and power equipment under the influence of excess pressure, mechanical, thermal loads and other factors, there is an accumulation of fatigue and other damage to buildings and metallic structural elements, leading to leakage of adverse processes leading to equipment failures with serious consequences that affect fire and industrial safety.
In this paper considered the use of electromagnetic-acoustic method together with the method of dynamic identification of stress-strain state and the level of damage to metal equipment and the application of integrated criteria for a comprehensive assessment of current condition of the process equipment.
The measurement applies second order fuzzy control. The paper discusses the features of synthesis of fuzzy controller based on experimental data: the formation of linguistic variables input and output signals, synthesis algorithm of production rules. The application of production rules with a double consequent possible to synthesize the fuzzy controller with the required accuracy. High accuracy, smooth nonlinear multidimensional characteristics, ease of synthesis allow using this controller not only in technological process control systems, but also in solving simulation problems and creating multidimensional nonlinear dependencies.
The paper deals with the optimization of the process of calculating the results of the measurement by a serial connection of fuzzy controllers. Since the fuzzy controller is a static unit, the serial connection will also be non-linear static unit, which can be represented as a fuzzy controller.
Application of the second order fuzzy controller takes into account the effects of temperature and thickness of metal of the control object. As a result, electromagnetic acoustic method allows not only to assess the class of stress-strain state, but also to calculate the exact value of the internal stress of the metal.
Currently, one of the urgent problems of modern gas industry is an energy–saving and energy–efficient use of energy resources. One solution to these problems is to reduce the cost of production of thermal energy, by increasing the coefficient of performance (efficiency) of the boiler equipment. This can be achieved by using modern gas-burning devices – gas burner.Gas burner – a device that supplies the required amount of mixture gas and an oxidizer (oxygen or air), creates the conditions for their mixing, transports the resulting mixture to the point of combustion and provides efficient gas combustion. In this gas-burning device must pass all state tests must be made on a specialized company and meet all modern standards and requirements. There are gas burners in which the combustion is supplied to the place and the gas and the air or gas only. With that, in the first case, when supplied with gas and air, the inside of the premixing gas burner does not occur. One of the factors responsible for the efficient operation of the gas burner is the lack of breakthrough phenomena and flame lift. The method of burning gaseous fuels is determined by the construction of gas-burning device and the degree of efficiency and lack of chemical incomplete combustion will depend on its fulfillment.
Most gas–burning devices have common design elements, regardless of their type, such as a nozzle, mixer, burner nozzle, combustion stabilizer. It gives an opportunity for more in-depth study of a particular device gas–burning devices, as well as for the further development and improvement of the parameters of its work.