DYNA JOURNAL ENGINEERING

Key words:

Bomba de propulsión por chorro de agua, Características hidráulicas y de empuje, Coeficiente de presión, Water-jet propulsion pump, Hydraulic and thrust characteristics, Pressure coefficient

Article type:

ARTICULO DE INVESTIGACION / RESEARCH ARTICLE

Section:

RESEARCH ARTICLES

Water-jet propulsion pump produces an action force by the flow of water at the outlet that is under a free water state when it does not suffer from constraints resulting from a pipeline or valve error, its thrust characteristics are also influenced by water flow characteristics. The calculation and experiment models of the hydraulic and thrust characteristics of a miniature water-jet propulsion pump were proposed in this study in order to determine the relationships between the hydraulic and thrust characteristics of the water-jet propulsion pump. We established the hydraulic calculation model by using the velocity coefficient method and thrust prediction, whereas the experiment model under open state was established by combining the working characteristics of the water-jet propulsion pump. The pressure coefficient at the outlet of the water-jet propulsion pump, velocity distribution at the outlet section, thrust characteristics under different revolution speeds, and the dynamic characteristics of different distances from nozzle to pool bottom were studied based on fluid dynamics and momentum theorem, after which model accuracy was verified through the experiment. Results show that the flow of the miniature water-jet propulsion pump presents a linear relationship with elevated pump revolution speed, and that the area of axial velocity being smaller than or equal to -1.5 m/s has positive correlations with both the revolution speed and the distance from nozzle to pool bottom. Results also indicated that the thrust of the miniature water-jet propulsion pump is influenced by the distance from the nozzle to the bottom: when the distance is greater than 0.8 m, the experiment pool has no influence on the thrust of the water-jet propulsion pump. This research results are of great significance in establishing a experiment stand of a miniature water-jet propulsion pump and its performance evaluation.

Keywords: Water-jet propulsion pump, Hydraulic and thrust characteristics, Pressure coefficient