冷却塔中新型混流式水轮机设计

通过数值模拟和试验两种方法,开发出一种新型高比转速混流式水轮机,配备相应变比的减速器,代替冷却塔中的风扇电动机,以达到节能的目的.根据冷却塔水轮机工作环境的特点,为尽量减小水轮机尺寸,在结构设计方面提出了金属梯形蜗壳和单列环形导叶.通过数值模拟,分析了不同的导叶形式、转速、叶片安放角对水轮机性能的影响.通过对比,选取负曲度导叶形式,选择最优单位转速及叶片安放角,确定最优性能的水轮机数模方案.通过物模试验证明所开发的高比转速混流式节能水轮机尺寸能够满足冷却塔要求,其效率高,性能稳定,可以在有条件的地方推广应用.

A new type of Francis turbine applied in cooling towers

In order to save energy,a new type of Francis turbine with high-specific speed was developed to replace fan motor in the cooling tower equipped with a suitable reducer by numerical simulation and model test.According to the features of Francis turbine operation environment,metal trapezoidal volute and uniseriate ring guide vanes were applied in the structural design.The forms of vanes,blade stagger angle and the rotational speed were analyzed by numerical simulation.The negative curvature guide leaf form,the optimum rotational speed and blade angle are selected as the optimal plan.The model test results show that the high-specific speed hydraulic turbine developed meets the dimension requirement and has high efficiency and stable performance,which can be popularized and applied in the capable local places.