Patent ID: 8812238

Claim:
A sensor assembly, comprising: A first optical computing device having an integrated computational element (ICE) configured to optically interact with a fluid stream and detect a first characteristic of a substance within the fluid stream, the optical computing device being configured to generate a first signal corresponding to the first characteristic; a parameter sensor configured to measure a second characteristic of the fluid stream and generate a second signal corresponding to the second characteristic; and a processor communicatively coupled to the optical computing device and the parameter sensor, the processor being configured to receive the first and second signals and determine a mass flow rate of the substance, wherein optically interacted light is generated through optical interaction of the ICE with the fluid stream and the optical computing device further includes a detector arranged to receive the optically interacted light and generate the first signal, and wherein the parameter sensor comprises a second optical computing device including an ICE configured to optically interact with the fluid stream and generate optically interacted light and a detector arranged to receive the optically interacted light and generate the second signal; the ICE of the first optical computing device being configured to interact with the fluid stream at a first point along a flow path and the ICE of the second optical computing device being configured to interact with the fluid stream at a second point along the flow path that is spaced apart from the first point; and the processor being further configured to determine a velocity of the fluid stream based at least in part on the first and second signals.