不同冷气/燃气温比下高温涡轮叶片旋流冷却流固耦合特性研究

采用流固耦合方法对燃气轮机高温涡轮叶片旋流冷却结构进行数值模拟分析。探究了不同冷气/燃气温度比条件下旋流冷却的流动与传热特性、叶片前缘区域固体温度、热应力以及热应变分布。研究表明：在进气腔入口雷诺数固定的条件下，随着温度比升高，冷气密度降低，冷气流速逐渐提升，同时湍动能升高，靶面努塞尔数逐渐升高；当温度比较低时冷气的流速较低、单位时间冷气带走的热量较少，当温度比较高时冷气温度较高、单位质量冷气所能吸收的热量有限，靶面处热流密度先升高后降低。受靶面热流密度分布影响，随着温度比升高，叶片前缘固体的温度、热应力以及热应变先降低后升高。

Study on Fluid-Structure Coupling Characteristics of Gas Turbine Blade Swirl Cooling under Different Coolant-Gas Temperature Ratios

The fluid structure coupling method was utilized to simulate and analyze the swirl cooling structure of gas turbine high temperature blade. The flow and heat transfer characteristics of swirl cooling, and the temperature, thermal stress and thermal strain distribution of blade leading edge solid were explored under the conditions of different coolant gas temperature ratios. Results show that under the condition of a certain Reynolds number at the intake chamber inlet, as the temperature ratio increases, the coolant density decreases, the coolant flow velocity gradually increases, there is an increase in turbulent kinetic energy at the same time, and the target wall Nusselt number gradually increases. Since the coolant flow velocity is lower when the temperature ratio is low, the amount of heat taken away by the coolant per unit time is less. When the temperature ratio is relatively high, the coolant temperature is higher, and the heat absorbed per unit mass of the coolant is limited, so the heat flux for the target wall increases first and then decreases. Affected by the heat flux distribution, the blade leading edge solid temperature, thermal stress and thermal strain will first decrease and then increase with increasing coolant gas temperature ratio.