Numerical Simulation And Experimental Study Of Internal Cooling Pump With Mechanical Seal

Seal and cooling problems of Pumps have attracted people’s thinking and continuousimprovement for a long time. Old technology was replaced by new technologies, and constantlypromote the pump design ideas. The pump seal and cooling issue is a more complicated issue. However,a very good technology can also bring great benefits to the pump seal cooling problems. Therefore,the study of internal cooling pumps with mechanical seal and find the optimal design are verymeaningful. In this paper, the application of numerical simulation software Fluent to ordinarycentrifugal pump and shaft openings of internal cooling pump with mechanical seal in the internalpressure, velocity and temperature fields at runtime numerical simulation studies are very meaningful.At the same time, experimental tests methods can verify the reliability of the results, hoping thesimulation results were able to be applied to the actual project.Firstly, the principles and methods of calculation of the CFD was expound from the perspectiveof the mathematical theory in this paper, and then create a two-dimensional model and mesh. Aftersetting the initial and boundary conditions, ordinary centrifugal pump and this article focuses onobject-cooled mechanical seal pumps were simulated. Finally, the experimental data is used to validatethe simulation data. Details and results of this paper are as follows:1. Internal cooling pump with mechanical seal was conducted simulation study, which has a6mmaperture. The results shows that with the increase of the running time, the temperature of heat sourcerise first and fall down, and finally leveled off. It is such an innovative idea to open up a new coolingflow channel, the fluid in which the circulation of the heat source has been cooled. Meanwhile, thecooling fluid is also removed impurities accumulated in heat source. In the long run, such a design toincrease the operating life of the pump plays a vital role.2. Firstly，ordinary centrifugal pumps and internal cooling pump with mechanical seal wereselected for numerical simulation, which has a6mm aperture and analyze pressure distribution,velocity distribution and temperature distribution. The results shows that in the cooling flow channel,the second one is relatively stable pressure distribution, velocity distribution and no vortex. At thesame time, from the temperature distribution, energy of heat source is constantly taken away. Clearly,internal cooling pump with mechanical seal is superior to ordinary centrifugal pump. 3. Secondly, two internal cooling pumps with mechanical seal are used for numerical simulation,one has a6mm aperture, and the other has an8mm aperture. Essentially, the internal pressure field ofthe two pumps are the same. Because the gap between the apertures is only2mm, the effect is not veryobvious. Presumably, if the diameter of the aperture could be larger, the effect would be better. Whenthe flow field is stable, it is easy to find hat even though there is a clear exit narrow passage vortex,but within the inner cooling channels, the velocity distribution is very uniform. This creates betterconditions for the cooling fluid to remove excess heat. In the temperature distribution, both the highesttemperature of the two heat sources are fairly. The former temperature is around52℃, and the lattertemperature is about49℃. This further illustrates the increasing aperture openings will enhance thecooling effect.4. Some experiments were used to prove the reliability of the numerical simulation. The maincontent of the test is to compare the temperature distribution of the experiment and the temperature ofnumerical simulation under3conditions (Ordinary centrifugal pump, internal cooling pump withmechanical seal which has a6mm aperture and internal cooling pump with mechanical seal which hasan8mm aperture). The results showed that in the heat source the cooling effect of internal coolingpump with mechanical seal is better than ordinary centrifugal pump. Experiments also show that thelarger the aperture shaft openings, the better effect of the cooling is.