The operation efficiency increase of condenser KP-1650 for drive turbine OK-12A at the Zaporizhia NPP power unit for turbine K-1000-60/1500.
Students Name: Andreitsev Artem
Qualification Level: magister
Speciality: Heat and Power Engineering
Institute: Institute of Power Engineering and Control Systems
Mode of Study: part
Academic Year: 2022-2023 н.р.
Language of Defence: ukrainian
Abstract: Andreitsev A. V., Rymar T. I. (supervisor). The operation efficiency increase of condenser KP-1650 for drive turbine OK-12A at the Zaporizhia NPP power unit for turbine K-1000-60/1500. Master’s thesis. – Lviv Polytechnic National University, Lviv, 2022. Extended abstract The task of intensifying the heat exchange process and creating highly efficient heat exchange devices has become extremely relevant in modern energy. In some cases, the heat exchangers of some installations have such large dimensions that they exceed the dimensions of the main equipment. In other cases, the low intensity of heat exchange limits the possibilities of solving the tasks. One of the important indicators of the quality of a heat exchange device is the efficiency of the heat exchange surface, the value of which is determined by the ratio of the amount of transferred heat to the power spent on pumping the coolant. By increasing the intensity of heat exchange processes, it is possible to achieve not only an increase in the efficiency of the heat exchange equipment, but also a reduction in their dimensions. The problem of intensification of heat exchange is especially relevant in cases where one or both heat carriers have low heat transfer coefficients [1, 2]. The difficulty of creating an effective heat exchange device for power plants is not only in achieving high thermal and aerodynamic indicators. In addition to maintaining these indicators, heat exchangers must be reliable in operation, simple in construction, technological in production and have a low cost. A promising way to improve the efficiency of the heat exchange surface is the use of profiled pipes with discrete turbulators [1-3], which contribute to the formation of a vortex structure of the flow directed to the pipe wall, which ensures an anticipatory increase in heat exchange compared to an increase in accompanying pressure losses. Study object – thermal processes in the KP-1650 condenser of the system of the feeding turbopump unit of the NPP power unit with the K-1000-60/1500 turbo installation Scope of research – methodical approaches to solving the problems of calculation substantiation of increasing the reliability of the KP-1650 condenser of the system of the feeding turbopump unit of the K-1000-60/1500 turbine due to the implementation of heat exchange intensification measures. Goal of research: increasing the efficiency of the KP-1650 condenser of the K-1000-60/1500 turbine feed turbopump unit system, improving the design of the tube bundle by introducing profiled heat exchange tubes. The master’s thesis considers the option of improving the design of the tube bundle of the condenser of the OK-12A turbo-drive turbine by introducing profiled heat exchange tubes in order to intensify heat exchange. The idea of using profiled pipes is related to the desire to intensify heat transfer due to the possibility of increasing the speed of the external heat carrier due to the lower aerodynamic resistance of such pipes, compared to pipes of round cross-section. A relatively small number of works are devoted to the study of heat transfer and aerodynamic resistance in bundles of profiled pipes. The paper analyzes the system of the feeding turbopump unit of the K-1000-60/1500 turbine. A number of technological requirements for the main equipment of the system and its composition have been analyzed. Usually discrete-rough channels include channels and pipes with various protrusions on the inner surface. These are most often: screw single- and multi-turn smoothly delineated protrusions, which are obtained according to widely known technology with the help of rolling rollers or discs; pipes with a spiral-screw wire insert; transverse, periodically located, smoothly delineated protrusions obtained with the help of rollers or disks; transverse, periodically located, rectangular and square inserts; channels and pipes with internal threads. It is well known that the intensification of heat exchange in pipes with the help of protrusions formed due to ring and screw rolling has a number of advantages compared to other designs of intensifiers: the grooves formed on the outer surface of the pipe in the case of rolling the protrusions intensify heat exchange on the outer surface as well; rolling technology is simple; the existing technology of assembly of shell and tube heat exchangers is quite applicable for rolled tubes. In the master’s thesis, the thermal calculation of the KP-1650 condenser of the OK-12A turbo-driven pump with smooth tubes was performed in order to determine its heating area according to the calculated data. The thermal and design calculation of the KP-1650 capacitor with non-smooth (profiled) tubes was also performed in order to determine its heating area according to the calculated data. Keywords: heat transfer, heat transfer intensification, reliability of work, profiled tubes. References 1. Bodnar L. A., Stepanov D. V. (2009). Effective methods of intensification of heat exchange in circular channels. Visnyk Khmelnytskoho natsionalnoho universytetu. – № 3 – РР. 73 – 78. 2. Rymar T. I. (2021). Heat exchange and hydrodynamic characteristics of unified packings of the package of the cold layer of the regenerative rotary air heater. Visnyk Natsionalnoho tekhnichnoho universytetu «Kharkivskyi politekhnichnyi instytut». Seriia: Enerhetychni ta teplotekhnichni protsesy y ustatkuvannia. – № 3 (7). – РР. 51 – 54. 3. Arseniev P.Iu., Tovazhnianskyi L.L., Arsenieva O.P. (2019). Criteria for comparing modified channels in heat exchange devices when using passive methods of heat transfer intensification. Intehrovani tekhnolohii ta enerhozberezhennia. – № 4. РР. 3 – 13.