Wang S.,Shenyang Bureau
Harbin Gongcheng Daxue Xuebao/Journal of Harbin Engineering University | Year: 2012
In order to find the design law that enables a mid-loaded turbine blade to be inserted into an aft-loaded turbine blade, the first stator of a four-stage power turbine was researched by the three-dimensional fluid dynamics software NUMECA. The camber curve and side curve of the blade were controlled by using a Bezier curve. Numerical simulation shows that when keeping the axial length invariant, narrowing the tangential length of the camber curve of the turbine and in the meantime increasing the thickness of the blades can control the throat area, and thereby obtain aft-loaded turbine cascades, which are advanced in performance and matching with the original ones. Study of three-dimensional flow fields shows that aft-loaded turbine cascades can reduce both profile loss and secondary flow loss. The new turbine cascades which are characterized by aft-loaded airfoil increase the turbine efficiency by 0.62%.
Yu J.,Shenyang Bureau |
Xu J.-L.,Shenyang Bureau |
Chen W.-X.,Shenyang Bureau |
Tang Y.-Y.,Shenyang Bureau
Hedongli Gongcheng/Nuclear Power Engineering | Year: 2012
A typical three-loop pressurized water reactor (PWR) as reference planted is chose, and the PWR severe accident analysis models based on RELAP5/SCDAP/MOD3.2 code are developed. The best estimate calculation of hot leg large break LOCA of 18 cm without mitigating measures is performed. The mitigating capability of injection to the accident is studied when peak core surface temperature reaches 1100 K, 1300 K and 1500 K respectively. The results show that the injection occasion plays an important role in the accident progression. Injection during early stage will prevent core from melting effectively. However, injection during later stage may deteriorate the progression of severe accident and accelerate of core melt.