METHOD FOR DETERMINING SHAPE OF HYDRAULIC-TURBINE BLADES FOR TURBODRILLING Russian patent published in 1997 - IPC

FIELD: oil and gas industries; rotation drill hydraulic drives. SUBSTANCE: blade shape determination is based on using desired line of entrance edge, desired profile in midsection, desired width of cascade in section Z under discussion and is describes by parametric expression , where R(α,z) is profile curvature radius found by solving differential equation , where , V(Z) is entrance velocity; ν is kinematic viscosity; α is flow turn angle; α₁ is flow entrance angle; x₁(x),y(z) are coordinates of entrance edges; X, Y, Z is rectangular coordinate system; X-axis is perpendicular to cascade front; Y-axis is along cascade front; Z-axis is along blade height. EFFECT: reduced energy loss of washing fluid and improved efficiency of turbodrill due to elimination of vortices in interblade channel of turbine cascades.