@ARTICLE{Kalenik_M._Empirical_2016, author={Kalenik, M. and Chalecki, M. and Wichowski, P. and Kozioł, A. and Babych, M.}, volume={vol. 16}, number={No 3}, journal={Teka Commission of Motorization and Power Industry in Agriculture}, howpublished={online}, year={2016}, publisher={The Lublin Branch of the Polish Academy of Sciences}, abstract={The paper presents the analysis of results of the investigations concerning a vertical pipe submersion coefficient h/L with an air-water mixer of the described type. The investigations were performed on an air lift pump testing stand, constructed in a laboratory on a scale of 1:1. At first, the paper presents the possibilities of application of air lift pumps. The investigations to date have been briefly characterized and a research problem formulated. Then the paper describes the construction and working principle of the air lift pump testing stand, constructed in a laboratory. It presents the methodology of derivation of empirical formulas for calculation of vertical pipe submersion coefficients h/L. The comparative analysis of the values of h/L determined in the measurements with the values of h/L calculated using the derived empirical formulas was carried out. The research scope encompassed the derivation of the aforementioned empirical formulas for five fixed values of air lift pump delivery head H, comparison of the obtained values h/L determined in the measurements with the values of h/L calculated using the derived empirical formulas and the improved analytical Stenning-Martin model. To derive the empirical formulas for calculation of the vertical pipe submersion coefficient h/L, the dimensional analysis and multiple regression was applied. The investigations of the vertical pipe submersion coefficient h/L were carried out for the vertical pipe internal diameter d = 0.04 m and for the fixed delivery heads H: 0.45, 0.90, 1.35, 1.80, 2.25 m. The values calculated using the derived empirical formulas (23), (24), (25), (26), (27) coincide with the values of h/L determined in the measurements for the whole range of the investigated delivery heads H. On the other hand, the values of h/L calculated using the improved analytical Stenning-Martin model do not coincide with the values of h/L determined in the measurements for the delivery heads H equal 0.45 and 0.90 m, whereas they are comparable for H equal 1.35, 1.80, 2.25 m. For the tested air lift pump with the air-water mixer of the described type (Fig. 2), the maximum air pressure should not exceed pp = 145 kPa, because for higher pressures the water flow rate diminishes. In the air lift pump being tested, the water flow rate Qw grows along with the rise in the air flow rate and in the vertical pipe submersion coefficient h/L whereas falls along with the rise in the delivery head H.}, type={Artykuły / Articles}, title={Empirical formulas for calculation of submersion coefficient of vertical pipe in air lif tpump}, URL={http://journals.pan.pl/Content/108389/PDF-MASTER/Kalenik_Babych.pdf}, keywords={air lift pump, two-phase flows, air-watermixer, vertical pipe submersion coefficient}, }