Three - Dimensional Numerical Simulation Of Volute Based On Incomplete Corner Turbine

Spiral case is the first set of turbine flow components. It is to guarantee the water can enter the water guide ring evenly, and can also format circulation before entering the water guide. As an important form of water bodies, the passage of spiral case of incomplete corners is divided into two parts, which are the volute section and the non-volute section. In the scroll portion, the flow is more uniform, which matches the design values perfectly, but in non-scroll part, due to lack of constraints to the water flow, flow which is extremely uneven goes into the water guide directly, resulting in the circumferential direction uniformity is poor, and this uniformity extend to the entire unit, and it will increase the energy loss of the unit, affecting the stability of the unit. Therefore, it is necessary to study the volute flow of turbine which does not completely wrap angle.This paper takes ZZ560-LH-1130 model turbine of Er jiang plant 1-2# unit for the study. According to its turbine parameters, using mathematical analysis methods, without considering the constraints of its power plant size, section size in different wrap angle include 150°,180° and 210°ere calculated. Three-dimensional solid model of the different corners of concrete volute were built with the help of Pro/E three-dimensional modeling software. These three models were simulated and calculated by fluent computing software. According to observation and analysis of these three models of internal water pressure distribution, velocity distribution, as well as the comparative analysis of the flow characteristics of each model.Analysis results were as follows:The internal flow three model is basically the same, it is more uniform in the volute section, less liquidity in the non-volute section and nose. Comprehensive comparison of the three models of pressure distribution, velocity distribution shows the flow of the concrete volute model of 150°is worst, internal flow uniformity of 210° is the best; In the nose, with the wrap angle increases, the flow pattern has also been improved. Especially for 210°, After simple repairing the concrete volute,its nose flow pattern has been improved a lot. In summary, the internal flow of 210°Corners of the concrete volute is the best, but the increase of the angle is bound to increase the investment of power station construction, so we need to take many things into consideration for the choice of the corners.