Abstract: A fluid control system is provided that in one form includes a first flow channel, a second flow channel, a heater disposed in the second flow channel, and a fluid control device disposed upstream from the first and second flow channels. When the heater is turned on, the fluid control device changes a fluid flow rate through at least one of the first flow channel and the second flow channel. In another form, the fluid control system includes a bypass conduit, a heater disposed within the bypass conduit, and a fluid control device disposed near the inlet and outlet of the bypass conduit. In still another form, the fluid control system includes a regeneration device disposed downstream from at least one exhaust aftertreatment system and closes an outlet of the exhaust pipe.

Abstract: A method of predicting the temperature of a resistive heating element in a heating system is provided. The method includes obtaining resistance characteristics of resistive heating elements and compensating for variations in the resistance characteristics over a temperature regime. The resistance characteristics of the resistive heating element include, but are not limited to, inaccuracies in resistance measurements due to strain-induced resistance variations, variations in resistance due to the rate of cooling, shifts in power output due to exposure to temperature, resistance to temperature relationships, non-monotonic resistance to temperature relationships, system measurement errors, and combinations of resistance characteristics. The method includes interpreting and calibrating resistance characteristics based on a priori measurements and in situ measurements.

Abstract: An exhaust system is provided that includes an exhaust aftertreatment unit, first and second exhaust pathway in communication with and upstream of the exhaust aftertreatment unit, a thermally activated flow control device operable in a first and second mode, and a thermal storage device. In the first mode, the flow control device permits exhaust to flow to the aftertreatment unit through the first pathway and inhibits flow through the second pathway. In the second mode, the flow control device permits exhaust flow to the aftertreatment unit through the second pathway and inhibits flow through the first pathway. The flow control device may switch between the first and second modes based on a change of temperature. The thermal storage device is within the second pathway, stores thermal mass, and provides thermal insulation to enable a catalyst of the aftertreatment unit to maintain a predetermined temperature for a predetermined time.

Abstract: A method for operating a heater system including a resistive heating element having a material with a non-monotonic resistivity vs. temperature profile is provided. The method includes heating the resistive heating element to within a limited temperature range in which the resistive heating element exhibits a negative dR/dT characteristic, operating the resistive heating element within an operating temperature range that at least partially overlaps the limited temperature range, and determining a temperature of the resistive heating element such that the resistive heating element functions as both a heater and a temperature sensor. The resistive heating element can function as a temperature sensor in a temperature range between about 500° C. and about 800° C., and the non-monotonic resistivity vs. temperature profile for the material of the resistive heating element can have a local maximum and a local minimum.

Abstract: A control system for use in a fluid flow application includes a heater and a control device. The heater has at least one resistive heating element and the heater is operable to heat fluid. The control device determines at least one flow characteristic of a fluid flow based on a heat loss of the at least one resistive heating element and determines a mass flow rate of the fluid based on the at least one flow characteristic and a property of the at least one resistive heating element. And the property of the at least one resistive heating element includes a change in resistance of the at least one resistive heating element under a given heat flux density.

Abstract: A heater is provided that includes at least one resistive heating element having a material with a non-monotonic resistivity vs. temperature profile and exhibiting a negative dR/dT characteristic over a predetermined operating temperature range along the profile. The heater can include a plurality of circuits disposed in a fluid path to heat fluid flow.

Abstract: A heater system for an exhaust system is provided. The heater system includes a heater disposed in an exhaust conduit. The heater includes a plurality of heating elements disposed in the exhaust conduit. A heating control module controls the plurality of heating elements differently according to operating conditions specific to each heating element. In other forms, the heater system for an exhaust system has a plurality of heating zones, instead of a plurality of heating elements. The heating control module controls the plurality of heating zones differently according to operating conditions specific to each heating zone.

Abstract: A control system for use in a fluid flow application is provided. The control system includes a heater having at least one resistive heating element. The heater is adapted to heat the fluid flow. The control system further includes a control device that uses heat loss from at least one resistive heating element to determine flow characteristics of the fluid flow.

Abstract: A heater system includes a heater bundle. The heater bundle includes a plurality of heater assemblies. Each heater assembly includes a plurality of heater units and an insulating material, and each heater unit defines at least one independently controlled heating zone. The heater bundle includes power conductors electrically connected to each of the independently controlled heating zones in each of the heater units. The heater bundle includes a power supply device configured to modulate power to each of the independently controlled heater zones of the heater units through the power conductors. A voltage is selectively supplied to each of the independently controlled heating zones such that a reduced number of independently controlled heating zones receives the voltage at a time or at least a subset of the independently controlled heating zones receive a reduced voltage at all times.

Abstract: A heating apparatus for a fluid flow system having a fluid conduit includes at least one heater element and a support member within the conduit. The at least one heater element includes a resistance wire, a sheath, and an electrically insulating material. The sheath has a closed profile shape that extends along a tortuous path through the container body and surrounds the resistance wire along the tortuous path. The insulating material is disposed about the wire between the wire and the sheath. The support member restricts movement of the at least one heater element relative to the fluid conduit. The support member defines a corrugated geometry that follows the tortuous path while contacting the sheath along a majority of a length of the sheath. The support member increases heat transfer from the at least one heater element to a fluid flowing through the fluid conduit.

Abstract: A heater system for an exhaust system is provided. The heater system includes a heater disposed in an exhaust conduit. The heater includes a plurality of heating elements disposed in the exhaust conduit. A heating control module controls the plurality of heating elements differently according to operating conditions specific to each heating element. In other forms, the heater system for an exhaust system has a plurality of heating zones, instead of a plurality of heating elements. The heating control module controls the plurality of heating zones differently according to operating conditions specific to each heating zone.

Abstract: A method of controlling a heating system is provided that includes having at least one heater assembly, the heater assembly comprising a plurality of heater units, each heater unit defining at least one independently controlled heating zone, supplying power to each of the heater units through power conductors electrically connected to each of the independently controlled heating zones in each of the heater units, and modulating power supplied to each of the independently controlled heating zones. A voltage is selectively supplied to each of the independently controlled heating zones such that a reduced number of independently controlled heating zones receives the voltage at a time, or at least a subset of the independently controlled heating zones receive a reduced voltage at all times.

Abstract: A heating apparatus for an exhaust gas system, or a fluid flow system, is provided by the present disclosure. The heating apparatus has a container body and includes at least one heater element and a support member disposed inside the container body and configured for restricting movement of the at least one heater element in the container body. The support member defines a tortuous geometry and flanks opposed sides of the at least one insulated heater element along a majority of a length of the at least one insulated heater element, wherein the support member increases heat transfer from the at least one heater element to an exhaust gas flowing through the container body.

Abstract: A susceptor for use in a heated fluid flow system is provided. In one form, a susceptor is arranged within a conduit and adapted to absorb radiant energy from at least one heating element and inhibit the radiant energy from being absorbed by the at least one wall of the conduit and/or other components. In another form, the susceptor absorbs and inhibits the radiant energy from being absorbed by the outer wall of the conduit.

Abstract: An exhaust system is provided that includes an exhaust aftertreatment unit, first and second exhaust pathway in communication with and upstream of the exhaust aftertreatment unit, a thermally activated flow control device operable in a first and second mode, and a thermal storage device. In the first mode, the flow control device permits exhaust to flow to the aftertreatment unit through the first pathway and inhibits flow through the second pathway. In the second mode, the flow control device permits exhaust flow to the aftertreatment unit through the second pathway and inhibits flow through the first pathway. The flow control device may switch between the first and second modes based on a change of temperature. The thermal storage device is within the second pathway, stores thermal mass, and provides thermal insulation to enable a catalyst of the aftertreatment unit to maintain a predetermined temperature for a predetermined time.

Abstract: A heating apparatus for an exhaust gas system, or a fluid flow system, is provided by the present disclosure. The heating apparatus has a container body and includes at least one heater element and a support member disposed inside the container body and configured for restricting movement of the at least one heater element in the container body. The support member defines a tortuous geometry and flanks opposed sides of the at least one insulated heater element along a majority of a length of the at least one insulated heater element, wherein the support member increases heat transfer from the at least one heater element to an exhaust gas flowing through the container body.

Abstract: A method of predicting the temperature of a resistive heating element in a heating system is provided. The method includes obtaining resistance characteristics of resistive heating elements and compensating for variations in the resistance characteristics over a temperature regime. The resistance characteristics of the resistive heating element include, but are not limited to, inaccuracies in resistance measurements due to strain-induced resistance variations, variations in resistance due to the rate of cooling, shifts in power output due to exposure to temperature, resistance to temperature relationships, non-monotonic resistance to temperature relationships, system measurement errors, and combinations of resistance characteristics. The method includes interpreting and calibrating resistance characteristics based on a priori measurements and in situ measurements.

Abstract: A heater for use in heating a fluid flow through a passageway is provided that includes a continuous resistive heating element having a predefined shape that is directly exposed to the fluid flow. The predefined shape includes a cross-sectional geometry that provides a required heat distribution, structural strength, and reduced back pressure within the passageway. The predefined shape may include airfoils, while the cross-sectional geometry provides a required heat distribution, structural strength, and reduced back pressure within the passageway.

Abstract: A heater is provided that includes at least one resistive heating element having a material with a non-monotonic resistivity vs. temperature profile and exhibiting a negative dR/dT characteristic over a predetermined operating temperature range along the profile. The heater can include a plurality of circuits disposed in a fluid path to heat fluid flow.

Abstract: A method of controlling a heating system is provided that includes having at least one heater assembly, the heater assembly comprising a plurality of heater units, each heater unit defining at least one independently controlled heating zone, supplying power to each of the heater units through power conductors electrically connected to each of the independently controlled heating zones in each of the heater units, and modulating power supplied to each of the independently controlled heating zones. A voltage is selectively supplied to each of the independently controlled heating zones such that a reduced number of independently controlled heating zones receives the voltage at a time, or at least a subset of the independently controlled heating zones receive a reduced voltage at all times.