Determination of heat-transfer coefficients in multi-vortex heat-mass-exchange apparatus

   In this work, heat transfer coefficients from the working surfaces of a multi-vortex heat-and-mass exchange apparatus developed by the authors are determined along with dimensionless equations for calculating the heat transfer coefficients from the inner wall of a housing and bottom when generating. Numerical modelling is carried out using the ANSYS Fluent software package. When determining the velocity profile of a fluid in order to calculate the coefficient of heat transfer, the SST k-ω turbulence model is used. This allows for an adequate convergence in near-wall fluid and gas flow areas when simulating flows in similar constructions used, for example, to classify finely dispersed bulk solids. Dimensionless equations are obtained that relate the Nusselt number to the Reynolds and Prandtl numbers. Relationships are obtained for the increase in the heat transfer intensity as a function of the Reynolds number. It is established that the intensity of heat transfer from the inner wall in the multi-vortex apparatus exceeds the heat transfer from the bottom by 12.7–15.8 % depending on the Reynolds number. The values of heat transfer coefficients at the inner wall of the proposed apparatus can reach 14747 W/(m² ∙ K) at an average fluid flow rate of 1 m/s. The proposed multi-vortex heat-exchange apparatus ensures swirling gas or fluid flow in the annular gap between the branch pipe and unit housing to provide high heat transfer coefficients and, hence, high intensity of heat transfer, especially through the wall of the contact stage. The numerical studies demonstrate the possibility of achieving high values of specific heat flux through the wall of the contact stage, which enables the most efficient use of the apparatus in the processes associated with the additional heat supply or removal from the contact stage through its external.

1. Voinov N. A., Zhukova O. P., Lednik S. A., Nikolaev N. A. Mass transfer in gas-liquid layer on vortex contact stages. Teoreticheskie osnovy himicheskoj tehnologii. 2013; 47 (1): 62-67. http://doi.org/10.7868/S004035711301017X. (In Russ.).

2. Khafizov F. S., Afanasenko V. G., Khafizov I. F., Khaibrakhmanov A. S., Boev E. V. Use of vortex apparatuses in gas cleaning process. Chemical and Petroleum Engineering. 2008; 44 (7): 425-428. https://doi.org/10.1007/s10556-008-9081-z.

3. Nikolaev A. N., Ovchinnikov A. A., Nikolaev H. A. Highly efficient vortex apparatuses for complex treatment of large volumes of industrial gas emissions. Himicheskaya promyshlennost'. 1992; 9: 36–38. (In Russ.).

4. Dadvand A., Hosseini S., Aghebatandish S., Khoo Boo Cheong. Enhancement of heat and mass transfer in a microchannel via passive oscillation of a flexible vortex generator. Chemical Engineering Science. 2019; 207: 556-580. https://doi.org/10.1016/j.ces.2019.06.045.

5. Gorbunova A., Klimov A., Molevich N., Moralev I., Porfiriev D., Sugak S., Zavershinskii I. Precessing vortex core in a swirling wake with heat release. International Journal of Heat and Fluid Flow. 2016; 59: 100-108. https://doi.org/10.1016/j.ijheatfluidflow.2016.03.002.

6. Henze M., Von Wolfersdorf J., Weigand B., Dietz C. F., Neumann S. O. Flow and heat transfer characteristics behind vortex generators – a benchmark dataset. International Journal of Heat and Fluid Flow. 2011; 32 (1): 318-328. https://doi.org/10.1016/j.ijheatfluidflow.2010.07.005.

7. Lyandzberg A. R., Latkin A. S. Vortex heat exchangers and condensation in a swirling flow. Petropavlovsk-Kamchatskiy: Kamchatka State Technical University; 2004, 149 р. (In Russ.).

8. Deev V. I., Kharitonov V. S., Churkin A. N. Analysis and generalization of experimental data on heat transfer to supercritical pressure water flow in annular channels and rod bundles. Thermal Engineering. 2017; 64 (2): 142-150. https://doi.org/10.1134/S0040601516110021.

9. Tarasevich S. E., Fedyaev V. L., Yakovlev A. B., Morenko I. V. Experimental and numerical investigation of heat transfer in annular channels with flow twisting. In: Heat Transfer Summer Conference collocated with the ASME 2012 Fluids Engineering Division Summer Meeting and the ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels. 8–12 July 2012, Rio Grande. Rio Grande; 2012, vol. 2, р. 109-114. https://doi.org/10.1115/HT2012-58430.

10. Nasiri M., Etemad S. Gh., Bagheri R. Experimental heat transfer of nanofluid through an annular duct. International Communications in Heat and Mass Transfer. 2011; 38 (7): 958-963. https://doi.org/10.1016/j.icheatmasstransfer.2011.04.011.

11. Riyi Lin, Xiaoqian Wang, Weidong Xu, Xinfeng Jia, Zhiying Jia. Experimental and numerical study on forced convection heat transport in eccentric annular channels. International Journal of Thermal Sciences. 2019; 136: 60-69. https://doi.org/10.1016/j.ijthermalsci.2018.10.003.

12. Mauro A. W., Cioncolini A., Thome J. R., Mastrullo R. Asymmetric annular flow in horizontal circular macro-channels: basic modeling of liquid film distribution and heat transfer around the tube perimeter in convective boiling. International Journal of Heat and Mass Transfer. 2014; 77: 897-905. https://doi.org/10.1016/j.ijheatmasstransfer.2014.06.021.

13. Cotton J. S., Robinson A. J., Shoukri M., Chang J. S. AC voltage induced electrohydrodynamic two-phase convective boiling heat transfer in horizontal annular channels. Experimental Thermal and Fluid Science. 2012; 41: 31-42. https://doi.org/10.1016/j.expthermflusci.2012.03.003.

14. Wang Han, Bi Qincheng, Yang Zhendong, Gang Wu, Hu Richa. Experimental and numerical study on the enhanced effect of spiral spacer to heat transfer of super-critical pressure water in vertical annular channels. Applied Thermal Engineering. 2012; 48: 436-445. https://doi.org/10.1016/j.applthermaleng.2012.05.010.

15. Abou-Ziyan H. Z., Helali A. H. B., Selim M. Y. E. Enhancement of forced convection in wide cylindrical annular channel using rotating inner pipe with interrupted helical fins. International Journal of Heat and Mass Transfer. 2016; 95: 996-1007. https://doi.org/10.1016/j.ijheatmasstransfer.2015.12.066.

16. Togun H., Abdulrazzaq T., Kazi S. N., Badarudin A., Kadhum A. A. H., Sadeghinezhad E. A review of studies on forced, natural and mixed heat transfer to fluid and nanofluid flow in an annular passage. Renewable and Sustainable Energy Reviews. 2014; 39: 835-856. https://doi.org/10.1016/j.rser.2014.07.008.

17. Lorenzon A., Vaglio E., Casarsa L., Sortino M., Totis G., Saragò G., et al. Heat transfer and pressure loss performances for additively manufactured pin fin arrays in annular channels. Applied Thermal Engineering. 2021; 117851. https://doi.org/10.1016/j.applthermaleng.2021.117851.

18. Butcher H., Quenzel C. J. E., Breziner L., Mettes J., Wilhite B. A., Bossard P. Design of an annular microchannel reactor (AMR) for hydrogen and/or syngas production via methane steam reforming. International Journal of Hydrogen Energy. 2014;39(31):18046-18057. https://doi.org/10.1016/j.ijhydene.2014.04.109.

19. Deev V. I., Kharitonov V. S., Baisov A. M., Churkin A. N. Universal dependencies for the description of heat transfer regimes in turbulent flow of supercritical fluids in channels of various geometries. The Journal of Supercritical Fluids. 2018;135:160-167. https://doi.org/10.1016/j.supflu.2018.01.019.

20. Liu Huan-ling, Qi Dong-hao, Shao Xiao-dong, Wang Wei-dong. An experimental and numerical investigation of heat transfer enhancement in annular microchannel heat sinks. International Journal of Thermal Sciences. 2019; 142: 106-120. https://doi.org/10.1016/j.ijthermalsci.2019.04.006.

21. Du D. X., Tian W. X., Su G. H., Qiu S. Z., Huang Y. P., Yan X. Theoretical study on the characteristics of critical heat flux in vertical narrow rectangular channels. Applied Thermal Engineering. 2012;36:21-31. https://doi.org/10.1016/j.applthermaleng.2011.11.039.

22. Dekterev A. A. Mathematical modeling of swirling flows as applied to industrial problems. In: Teplomassoobmen i gidrodinamika v zakruchennyh potokah: materialy VI Vserossijskoj konferencii s mezhdunarodnym uchastiem = Heat and Mass Transfer and Hydrodynamics in Swirling Flows: Materials of the 6th All-Russian Conference with international participation. 21–23 November 2017, Novosibirsk. Novosibirsk: Kutateladze Institute of Thermophysics SB RAS; 2017, р. 16. (In Russ.).

23. Laptev A. G., Farahov T. M., Dudarovskaya O. G. Efficiency of transfer phenomena in the channels with chaotic packed layers. St. Petersburg: Strata; 2016, 214 р. (In Russ.).