REDUCTION IN THE INTENSITY OF HEAT AND MASS TRANSFER IN CRYOGENIC FLUID IN A HORIZONTAL RESERVOIR

An approach is proposed to increasing the time of storage of cryogenic fl uid in a horizontal cylindrical reservoir due to a reduction in the intensity of heat and mass transfer from its outer surface. A mathematical model has been developed for heat and mass transfer processes in cryogenic fl uid on the basis of equations of unsteady nonisothermal turbulent motion of incompressible fl uid. A k–ε turbulence model is used in the calculations. A comparison of the computational data with experimental fi ndings has shown the adequacy of the proposed model. Based on the mathematical model, a possibility is shown for organizing a cryogenic fl uid fl ow ensuring a reduction in the intensity of transfer of superheated liquid from the boundary layer near the reservoir surface into the zone of evaporation. We proposed a method for mechanical limitation of thermoconvective fl uid fl ow from the reservoir walls to its fl uid evaporation surface and a device for implementing this method. This device, unlike similar existing devices, has a small area of contact with the side surface of the reservoir and is invariant with regard to the level of cryogenic fl uid in it. A computational experiment showed the effi ciency of the proposed approach. Using the example of liquid nitrogen, hydrogen, and oxygen, it has been shown that the said device allows a reduction in the intensity of heating the surface of cryogenic fl uid evaporation in the reservoir and an increase in the time of its storage.
   
Author:  V. I. Ryazhskikh, A. A. Khvostov, D. A. Konovalov, V. A. Sumin, A. V. Ryazhskikh
Keywords:  cryogenic technology, gravitational heat convection, mathematical modeling
Page:  785