Abstract: A hybrid flow ratio controller system is provided, which includes an inlet configured to receive a total inlet fluid flow and three or more distribution channels. Each of the three or more distribution channels has a respective variable flow control valve and carries a respective portion of the total inlet fluid flow. The hybrid flow ratio controller further includes a controller operatively coupled to the respective variable flow control valves. The controller is configured to control a flow rate of at least a first distribution channel according to a predetermined flow ratio of the inlet fluid flow in accordance with a flow ratio control mode, to control a flow of at least a second distribution channel in either a flow rate control mode or a pressure control mode, and to control a third distribution channel in an overflow mode.

Abstract: A flow measurement system is provided, which is configured to receive multiple flow rates; retrieve multiple physical properties for multiple pure gases; estimate multiple physical properties for a gas mixture; estimate multiple flow parameters for multiple channels of a flow splitter using a mathematical model, multiple physical properties for the gas mixture, and multiple pressure values from pressure sensors of multiple channels; and estimate multiple flow splits using multiple flow parameters for the multiple channels of the flow splitter.

Abstract: A flow rate ratio control device is provided with a main flow path, a plurality of branch flow paths that branch off from a terminus of the main flow path, a plurality of fluid control devices that are provided respectively on each branch flow path, and that are each equipped with a valve and a pressure-based flow rate sensor that is disposed downstream of the valve, and an operation setting unit that establishes settings such that, based on the target flow rate ratio, any one fluid control device from among the plurality of fluid control devices is made to operate in a flow velocity control mode in which the flow velocity of a fluid is controlled upstream of each valve, and the remaining fluid control devices are made to operate in a flow rate control mode in which the flow rate is controlled based on the target flow rates.

Abstract: A flow rate ratio control device is provided with a main flow path, a plurality of branch flow paths that branch off from a terminus of the main flow path, a plurality of fluid control devices that are provided respectively on each branch flow path, and that are each equipped with a valve and a pressure-based flow rate sensor that is disposed downstream of the valve, and an operation setting unit that establishes settings such that, based on the target flow rate ratio, any one fluid control device from among the plurality of fluid control devices is made to operate in a flow velocity control mode in which the flow velocity of a fluid is controlled upstream of each valve, and the remaining fluid control devices are made to operate in a flow rate control mode in which the flow rate is controlled based on the target flow rates.