基于Multisim的恒压型热线风速测量系统电路仿真分析

Simulation and Analysis on Constant Voltage Hotwire Flow Velocity Measurement System Based on Multisim

为开展恒压型热线风速测量系统的优化设计,建立了基于Multisim的电路仿真模型,其中,热线探头采用PSpice模型实现其特性的模拟,恒压控制回路中采用了T型动态补偿网络以提高系统的频响。进行了恒压型控制回路元件参数和流场流速对系统动静态性能影响的仿真分析及热线探头时间常数原位测量仿真。结果表明:从Multisim电路仿真模型得到流场流速、补偿网络参数、控制回路输入电压和电阻等对系统动静态特性的影响规律与数值计算的一致,验证了在Multisim中开展恒压型热线风速测量系统仿真研究的可行性,同时,这种针对实际电路参数的仿真分析对恒压型热线风速测量系统的优化设计和制备具有重要指导意义。

To optimize the design of hotwire flow_velocity measurement system under constant voltage control loop（ CVCL）,circuit simulation model of the system is established based on Multisim,in which,hotwire probe characteristics are simulated by using PSpice model,T-Shape dynamic compensation network is adopted into CVCL to improve frequency response of the system. Dynamic and static characteristics of hotwire flow_velocity measurement system under CVCL are simulated and analyzed regarding to flow_velocity and components＇ parameters in CVCL,and in situ measurement simulation of hotwire probe time constant is also conducted. The simulation results show that the laws obtained in Multisim about the effect of flow_velocity,compensation network,input voltage and resistances in CVCL on system characteristics are in accordance with numerical calculation,and also demonstrates the feasibility of this methodology. At the same time,the simulation and analysis for actual circuit parameters could provide important guidance in the optimization design and preparation of hotwire flow_velocity measurement system under CVCL.