MATHEMATICAL MODEL OF THE HEATER WITH INTERMEDIATE HEAT
DOI:
https://doi.org/10.31471/1993-9981-2021-2(47)-83-95Keywords:
непрямий підігрів, кібернетична модель, теплопередача, енергетичний баланс, система управління.Abstract
Track heaters are one of the technological equipment’s elements of oil and gas condensate deposits during the transportation of oil, oil products and natural gas. It was found that it is advisable to use line heaters with an intermediate heat carrier (water), which is heated during combustion associated (commercial) gas and transfers heat to the process flow through the heat exchange surface for soft heating of viscous oils and oil products to avoid hydrate formation during throttling of natural gas, with the aim of further transportation through pipelines to the place of collection, processing and consumption. A significant part of scientific publications relates to improving the efficiency of such devices with the use of various technological innovations for heat recovery from flue gases, as well as the use of high-quality control systems. On the basis of the analysis of the heater as an object of automation, the main input, disturbing factors and output parameters of control and regulation were established, and the information structure of the heater as a cybernetic system was developed. Based on the equations of the material and heat balance of the apparatus, the mathematical model of the dynamics of the process of heating technological streams has been developed, which includes the differential equations of the heat balance of the product heat exchanger, intermediate heat carrier, flue gases in the gas duct formed during gas combustion. The system of equations is supplemented by equations of heat transfer through two heat exchange surfaces from water to the target product and from flue gases to an intermediate heat carrier. The linearization of the nonlinear components of the developed model in the vicinity of the operating point is carried out. Based on the obtained mathematical description of the heater, a block diagram of the model was synthesized, which shows the relationship of input parameters, control action and output variables in deviations from the base point of the operating mode.
Downloads
References
Gas fired water bath heaters. URL: https://epcmholdings.com/gas-fired-water-bath-heaters/.
Barreto C.V, Pires Luis F. G., Sarmento R. C. Тransient simulation of natural gas citygates stations. Proceedings of the 8th International Pipeline Conference IPC2010 September 27-October 1, 2010, Calgary, Alberta, Canada. URL: http://www.simdut.com.br/Trabalhos/IPC2010-31567.pdf
Rashidmardani A., Hamzei M. Effect of Various Parameters on Indirect Fired Water Bath Heaters’ Efficiency to Reduce Energy Losses. International Journal of Science and Engineering Investigations, 2013. Vol. 2, issue 12. P.17-25.
Azizi S. H., Rashidmardani A., Andalibi M. R. Study of Preheating Natural Gas in Gas Pressure Reduction Station by the Flue Gas of Indirect Water Bath Heater. International Journal of Science and Engineering Investigations, 2014. Vol. 3, issue 27. P.17-22. URL: http://www.ijsei.com/papers/ijsei-32714-03.pdf ISSN: 2251-8843.
Khanmohammadi S., Shahsavar A. Thermodynamic assessment and proposal of new configurations of an indirect water bath heater for a City Gate Station (a case study). Energy Equip. Sys, 2020. Vol. 8. No. 4. Dec. 2020. P. 349-365. URL: http://www.energyequipsys.com/article_241292_f1fc67b732305a7108c69cf11f6cab0d.pdf
Riahi М., Yazdirad B., Jadidi M., Berenjkar F., Khoshnevisan S., Jamali M., Safary M. Optimization of Combustion Efficiency in Indirect Water Bath Heaters of Ardabil City Gate Stations. MCS 7 Chia Laguna, Cagliari, Sardinia, Italy, September 11-15, 2011. URL:
Rastegar S., Kargarsharifabad H., Doost A.K., Rahbar N. Developing a Model for Predicting the Outlet Gas Temperature of Natural Gas Pressure Reduction Stations to Reduce Energy Loss. Journal of Heat and Mass Transfer Research 7, 2020. P.143-154. URL: https://jhmtr.semnan.ac.ir/article_4469_339ae1dfdccab8b200ef6dbcf8e8abfe.pdf
Incropera.F.P, DeWitt.D.P, Bergman T. L., Lavine А. S. Fundamentals of heat and mass transfer, 6th ed,2006. New York, John Wiley ISBN-13: *978-0-471-45728-2 (cloth), ISBN-10: 0-471-45728-0 (cloth)
Miheev M. A., Miheeva I. M. Osnovyi teploperedachi. Izd. 2-e, stereotip. M. : «Energiya», 1977. 344 s
Skoblo A.I., Molokanov YU.K., Vladimirov A.I., Sсhelkunov VA. Protsessyi i apparatyi neftegazopererabotki i neftehimii: Uchebnik dlya vuzov. 3-e izd., pererab. i dop. M. : OOO ‟Nedra-Biznestsentr‟, 2000. 677 s.
.png)
