The present invention provides a new method and apparatus for receiving signals containing information about a plurality of velocity profiles of a flow in a pipe and about a pressure gradient of the flow over a length of the pipe; and determining information about an injection of a chemical into the flow in the pipe based at least partly on the information contained in the signals.

The present invention provides a new method and apparatus for receiving signals containing information about a plurality of velocity profiles of a flow in a pipe and about a pressure gradient of the flow over a length of the pipe; and determining information about an injection of a chemical into the flow in the pipe based at least partly on the information contained in the signals.

The present invention provides a new method and apparatus for receiving signals containing information about a plurality of velocity profiles of a flow in a pipe and about a pressure gradient of the flow over a length of the pipe; and determining information about an injection of a chemical into the flow in the pipe based at least partly on the information contained in the signals.

The present invention provides a new method and apparatus for receiving signals containing information about a plurality of velocity profiles of a flow in a pipe and about a pressure gradient of the flow over a length of the pipe; and determining information about an injection of a chemical into the flow in the pipe based at least partly on the information contained in the signals.