为研究涡轮反转鼓风损失的影响因素,掌握可倒车动力涡轮反转鼓风损失控制策略与控制方法,以某船用可倒车动力涡轮为例,建立了计算模型。在1.0工况下以额定转速n为基础,分别计算了0.6n、0.8n、1.0n、1.1n转速下可倒车动力涡轮产生的鼓风损失,并分析对比了4种转速下可倒车动力涡轮的性能及鼓风损失的变化。同时对比研究不同旋向倒车涡轮内部流场,分析鼓风损失对流场参数的影响。由于可倒车动力涡轮自身的特殊结构,倒车涡轮叶型与正车涡轮叶型相反,正车涡轮正转时(即倒车涡轮反转)会不可避免地产生鼓风损失,这部分损失会消耗机组的功率。本文以功率作为鼓风损失的衡量标准,研究表明：机组正车运行时,倒车涡轮会产生鼓风损失,造成倒车级内流场参数出现异常,如出口压力高于进口压力、动叶栅的温升现象、输出功率为负等。1.1n转速下因鼓风产生的损失最高,损失占比也是最高,对比1.0n转速,效率相差不大,损失占比较1.1n转速低,机组输出功率高,考虑到实际,当效率相差不大时,功率为首选项,1.0n转速为机组最佳运行状态。

In order to study the influencing factors of turbine reversal windage loss and master the control strategy and control method of reversal windage loss of reversible turbine, a calculation model was established by taking a marine reversible turbine as an example.Under the working condition of 1.0, based on the rated speed n, the windage loss caused by the reversible turbine at the speeds of 0.6n, 0.8n, 1.0n and 1.1n was calculated respectively, and the characteristics of the reversible turbine and the change of the windage loss at four speeds were analyzed and compared.At the same time, the internal flow field of the reversible turbine with different rotating directions was compared and the influence of the windage loss on the flow field parameters was analyzed.Due to the special structure of the reversible turbine, the blade type of the reversible turbine is opposite to that of the normal turbine. When the normal turbine is rotating (the reversible turbine is reversed ), the windage loss will inevitably occur, which will consume the power of the unit. In this paper, power is used as a measure of windage loss. The research shows that when the unit is running, the reversible turbine will produce windage loss, resulting in abnormal flow field parameters in the reversible stage, such as the outlet pressure is higher than the inlet pressure, the temperature rise of the rotor blade cascade, and the output power is negative.At the speed of 1.1n, the windage loss is the highest, and the loss ratio is also the highest. Compared with the speed of 1.0n, the efficiency is not much different.The loss ratio is lower than the speed of 1.1n, and the output power of the unit is high. Considering the reality, when the efficiency is not much different, the power is the first choice, and the speed of 1.0n is the best operating state of the unit.

TK14

国家科技重大专项(J2019-II-0018-0039)