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 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 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 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 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 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.