GAS INSENSITIVE MASS FLOW CONTROL SYSTEMS AND METHODS

Gas insensitive systems and methods for controlling the mass flow rate of a gas through a primary conduit are disclosed. The method includes producing, in a secondary conduit, an assessment flow thathas a changing pressure; calculating a first measure of a flow rate of the assessment flow based upon a rate-of-change of the pressure of the assessment flow; and measuring the assessment flow with amass flow meter that is affected by the composition of the gas to produce a second measure of a flow rate of the assessment flow. An adjustment signal is generated based upon a difference between thefirst measure and the second measure, and a gas-corrected flow signal is generated by adjusting a measured-flow signal of a mass flow controller with the adjustment signal. The gas-corrected flow signal is used by the mass flow controller to control a flow rate of the gas through the primary conduit. 公开了用于控制通过主管道的气体的质量流速的气体不敏感的系统和方法。所述方法包括：在辅管道中产生具有变化压力的评估流；基于所述评估流的压力的变化率来计算所述评估流的流速的第测量；以及利用受所述气体的组成影响的质量流量计来测量所述评估流，以产生所述评估流