Abstract: A method for control of a flow network in order to improve the performance of the flow network comprises: (a) applying predetermined excitations at multiple control points within the flow network, wherein the multiple control points are at different branches of the flow network; (b) receiving measurements of changes in one or more flow parameter(s) in one or more flow path(s) in which flows of more than one of the different branches have been combined; (c) carrying out an analysis of the flow parameter measurements to identify variations induced by the applied excitations; (d) determining an adjustment to be made at one or more of the control point(s) in order to improve the performance of the flow network, for example by building and solving an optimization model; (e) making the determined adjustment to the control point(s) of the flow network or making an alternative adjustment decided upon by the flow network operator; and (f) repeating steps (a) to (e) one or more times to thereby iteratively improve the

Abstract: To determine properties of multiple oil and gas wells, oscillations at different test frequencies are applied to the flow rate and/or pressure of multiple wells. Measurements of flow rate and/or pressure and temperature in flows downstream of a production header of the multiple wells are then obtained. Such measurements from the flows of the multiple wells are subjected to a frequency analysis of the pressure, flow rate and/or temperature measurements to determine pressure, flow rate and/or temperature variations induced by the applied oscillations. Properties of the different wells of the multiple wells based on the results of the frequency analysis are thus determined.

Abstract: A method for control of a flow network in order to improve the performance of the flow network comprises: (a) applying predetermined excitations at multiple control points within the flow network, wherein the multiple control points are at different branches of the flow network; (b) receiving measurements of changes in one or more flow parameter(s) in one or more flow path(s) in which flows of more than one of the different branches have been combined; (c) carrying out an analysis of the flow parameter measurements to identify variations induced by the applied excitations; (d) determining an adjustment to be made at one or more of the control point(s) in order to improve the performance of the flow network, for example by building and solving an optimisation model; (e) making the determined adjustment to the control point(s) of the flow network or making an alternative adjustment decided upon by the flow network operator; and (f) repeating steps (a) to (e) one or more times to thereby iteratively improve the

Abstract: A method of well testing to determine properties of oil and gas wells 8 comprises: applying oscillations to the flow rate and/or pressure at multiple wells 8 wherein the oscillations applied at different wells of the multiple wells are at different test frequencies; receiving measurements of flow rate in flows downstream of a production header that combines the flows from the multiple wells 8, and/or receiving measurements of pressure and/or temperature from individual wells 8; carrying out a frequency analysis of the pressure, flow rate and/or temperature measurements to determine pressure, flow rate and/or temperature variations induced by the applied oscillations; and determining properties of the different wells 8 of the multiple wells 8 based on the results of the frequency analysis at the test frequencies for the wells 8.