某调节阀气动及振动噪声性能研究

为了降低汽轮机低工况运行时调节阀的振动噪声，设计一种多级节流调节阀，在汽轮机低工况运行时使用。采用吹风试验的方法对所设计调节阀在不同工况下的流量、振动、噪声多种特性进行了分析，得到其随着升程、压比的变化规律。选取某3个常用汽轮机调节阀与所设计调节阀进行对比试验，根据试验系统实际情况，以相同压比约0.5、相同质量流量约0.5 kg/s为基准进行了横向对比分析。结果表明：压比一定条件下调节阀的流量系数随着升程的增大而逐渐增大，升程一定条件下流量系数随着压比的增大呈现逐渐减小的趋势；在升程一定时，随着压比的增大，机脚加速度值呈现先减小后逐渐增大的趋势，调节阀受低频激励的影响较小，受中高频激励的影响较大；在压比为0.5时，随着升程的增大，调节阀的空气噪声值逐渐增大，压比大于0.5时，空气噪声值随着升程的增大而呈现先增大后略有减小的趋势，在升程一定时，随着压比的增大，空气噪声值基本呈现了逐渐减小的趋势；所设计的多级节流调节阀与某3个常用汽轮机调节阀相比在振动噪声抑制方面具有相对优势。

Study on Aerodynamic and Vibration Noise Performance of Regulating Valve

In order to reduce the vibration and noise of the regulating valve of the steam turbine under low working conditions, a multi stage throttle regulating valve was designed, which was used under low working conditions of the steam turbine. The flow, vibration and noise characteristics of the regulating valve under different working conditions were analyzed by means of blowing test, and the variation law with lift and pressure ratio was obtained. Three common turbine regulating valves were selected for comparative test with the designed regulating valve. According to the actual situation of the test system, the horizontal comparison analyses were carried out based on the same pressure ratio of about 0.5 and the same mass flow of about 0.5 kg/s. Results show that when the pressure ratio is constant, the flow coefficient of the regulating valve gradually increases with the increase of lift, and when the lift is constant, the flow coefficient shows a gradually decreasing trend with the increase of pressure ratio; when the lift is constant, as the pressure ratio increases, the foot acceleration value shows a trend of first decreasing and then gradually increasing. The regulating valve is less affected by low frequency excitation, but more affected by medium and high frequency excitation; when the pressure ratio is 0.5, the air noise value of the regulating valve gradually increases with the increase of lift. When the pressure ratio is greater than 0.5, the air noise value shows a trend of first increasing and then slightly decreasing with the increase of lift. When the lift is constant, the air noise value basically shows a trend of gradually decreasing with the increase of pressure ratio; the designed multi stage throttle regulating valve has relative advantages in vibration and noise suppression compared to three common turbine regulating valves.