An electromagnetic cooking device and cooking method to perform zone cooking is disclosed. The method includes scanning a resonant cavity in which a food load has been placed with RF feeds that are coupled to respective high power amplifiers; identifying resonant frequencies and corresponding phases of the RF feeds; storing a resonance map; classifying symmetries in the resonant map; determining paths defining stirring routes between poles of different symmetries; determining midpoints in the paths with a maximum unbalance between reflected powers of the respective high power amplifiers; classifying the unbalance in terms of power steered to the left and right sides of the food load; synthesizing a heating strategy for zone cooking using the classified unbalance; and implementing the heating strategy by causing the plurality of high power amplifiers and RF feeds to introduce electromagnetic radiation at specific selected frequencies and phases into the cavity based on the heating strategy.

An electromagnetic cooking device and cooking method to perform zone cooking is disclosed. The method includes scanning a resonant cavity in which a food load has been placed with RF feeds that are coupled to respective high power amplifiers; identifying resonant frequencies and corresponding phases of the RF feeds; storing a resonance map; classifying symmetries in the resonant map; determining paths defining stirring routes between poles of different symmetries; determining midpoints in the paths with a maximum unbalance between reflected powers of the respective high power amplifiers; classifying the unbalance in terms of power steered to the left and right sides of the food load; synthesizing a heating strategy for zone cooking using the classified unbalance; and implementing the heating strategy by causing the plurality of high power amplifiers and RF feeds to introduce electromagnetic radiation at specific selected frequencies and phases into the cavity based on the heating strategy.

Pasteurization systems, devices and methods are generally described that use synchronized peak electric and magnetic fields. Example pasteurization systems may include a first resonant circuit that includes a first capacitive element coupled to a first inductive element, a second resonant circuit that includes a second capacitive element coupled to a second inductive element. The first inductive element and the second capacitive element may be positioned about the first treatment region, and the second inductive element and the first capacitive element may be positioned about the second treatment region. A controller coupled to the first and second resonant circuits may provide a first signal to the first resonant circuit and a second signal to the second resonant circuit, phase shifted by a predetermined amount.

An apparatus and method for electromagnetic heating of a hydrocarbon formation. The apparatus includes an electrical power source; at least one electromagnetic wave generator for generating alternating current; at least two transmission line conductors positioned in the hydrocarbon formation; at least one waveguide for carrying the alternating current from the at least one electromagnetic wave generator to the at least two transmission line conductors; and a producer well to receive heated hydrocarbons from the hydrocarbon formation. The transmission line conductors are excitable by the alternating current to propagate a travelling wave within the hydrocarbon formation. At least one of the transmission line conductors include a primary arm and at least one secondary arm extending laterally from the primary arm. The at least one secondary arm includes at least one electrically isolatable connection for electrically isolating at least a portion of the secondary arm.

An apparatus and method for electromagnetic heating of a hydrocarbon formation. The apparatus includes an electrical power source; at least one electromagnetic wave generator for generating alternating current; at least two transmission line conductors positioned in the hydrocarbon formation; at least one waveguide for carrying the alternating current from the at least one electromagnetic wave generator to the at least two transmission line conductors; and a producer well to receive heated hydrocarbons from the hydrocarbon formation. The transmission line conductors are excitable by the alternating current to propagate a travelling wave within the hydrocarbon formation. At least one of the transmission line conductors include a primary arm and at least one secondary arm extending laterally from the primary arm. The at least one secondary arm includes at least one electrically isolatable connection for electrically isolating at least a portion of the secondary arm.

A hydrocarbon resource recovery system may include an RF source, and an RF antenna assembly coupled to the RF source and within a wellbore in a subterranean formation for hydrocarbon resource recovery. The RF antenna assembly may include first and second tubular conductors, a dielectric isolator, and first and second electrical contact sleeves respectively coupled between the first and second tubular conductors and the dielectric isolator so that the first and second tubular conductors define a dipole antenna. The RF antenna assembly may include a thermal expansion accommodation device configured to provide a sliding arrangement between the second tubular conductor and the second electrical contact sleeve when a compressive force therebetween exceeds a threshold.

A hydrocarbon resource recovery system may include an RF source, and an RF antenna assembly coupled to the RF source and within a wellbore in a subterranean formation for hydrocarbon resource recovery. The RF antenna assembly may include first and second tubular conductors, a dielectric isolator, and first and second electrical contact sleeves respectively coupled between the first and second tubular conductors and the dielectric isolator so that the first and second tubular conductors define a dipole antenna. The RF antenna assembly may include a thermal expansion accommodation device configured to provide a sliding arrangement between the second tubular conductor and the second electrical contact sleeve when a compressive force therebetween exceeds a threshold.

A hydrocarbon resource recovery system may include an RF source, and an RF antenna assembly coupled to the RF source and within a wellbore in a subterranean formation for hydrocarbon resource recovery. The RF antenna assembly may include first and second tubular conductors, a dielectric isolator coupled between the first and second tubular conductors, an RF transmission line having an inner conductor and an outer conductor extending within the first tubular conductor, the outer conductor being coupled to the first tubular conductor, and a feed structure coupled to the second tubular conductor. The inner conductor may have a distal end being slidable within the outer conductor and cooperating with the feed structure to define a latching arrangement having a latching threshold lower than an unlatching threshold.

An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing electrical power to at least one electromagnetic wave generator for generating high frequency alternating current; using the electromagnetic wave generator to generate high frequency alternating current; using at least one pipe to define at least one of at least two transmission line conductors; coupling the transmission line conductors to the electromagnetic wave generator; and applying the high frequency alternating current to excite the transmission line conductors. The excitation of the transmission line conductors can propagate an electromagnetic wave within the hydrocarbon formation. In some embodiments, the method further comprises determining that a hydrocarbon formation between the transmission line conductors is at least substantially desiccated; and applying a radiofrequency electromagnetic current to excite the transmission line conductors. The radiofrequency electromagnetic current radiates to a hydrocarbon formation surrounding the transmission line conductors.

An apparatus and method for electromagnetic heating of a hydrocarbon formation. The method involves providing electrical power to at least one electromagnetic wave generator for generating high frequency alternating current; using the electromagnetic wave generator to generate high frequency alternating current; using at least one pipe to define at least one of at least two transmission line conductors; coupling the transmission line conductors to the electromagnetic wave generator; and applying the high frequency alternating current to excite the transmission line conductors. The excitation of the transmission line conductors can propagate an electromagnetic wave within the hydrocarbon formation. In some embodiments, the method further comprises determining that a hydrocarbon formation between the transmission line conductors is at least substantially desiccated; and applying a radiofrequency electromagnetic current to excite the transmission line conductors. The radiofrequency electromagnetic current radiates to a hydrocarbon formation surrounding the transmission line conductors.