Abstract: Cost efficient, lightweight and rapid windshield deicing systems and methods are disclosed. The systems utilize step-up converters or inverters, or dual-voltage batteries, to provide a voltage high enough to deice a windshield in less than thirty seconds at ambient temperatures above ?10 C. Some of the disclosed systems include sensors for deicing element and ambient temperatures, and in some embodiments windspeed. All embodiments have a controller for limiting deicing time to that sufficient to melt a boundary layer of ice. The controller of embodiments with sensors computes deicing time as a function of ambient temperature. Embodiments interact with wiper systems to enable wipers to clear ice once the boundary layer is melted.

Abstract: A heat exchanger for exchanging heat between gasses such as air and a liquid or gaseous coolant has narrow spacing between exchanger surfaces for high efficiency. To avoid undue obstruction of gas flow due to ice buildup on the exchanger surfaces, the heat exchanger is equipped with sensors to monitor the gas flow and an actuator that widens the spacing between exchanger surfaces such that gas flow remains unimpeded. Embodiments provide for defrosting of the exchanger surfaces when an limit on spacing of exchanger surfaces is reached, and for relaxing the spacing to the original narrow spacing when defrosting is completed.

Abstract: Cost efficient, lightweight and rapid windshield deicing systems and methods are disclosed. The systems utilize step-up converters or inverters, or dual-voltage batteries, to provide a voltage high enough to deice a windshield in less than thirty seconds at ambient temperatures above ?10 C. Some of the disclosed systems include sensors for deicing element and ambient temperatures, and in some embodiments windspeed. All embodiments have a controller for limiting deicing time to that sufficient to melt a boundary layer of ice. The controller of embodiments with sensors computes deicing time as a function of ambient temperature. Embodiments interact with wiper systems to enable wipers to clear ice once the boundary layer is melted.

Abstract: An alternating electric field is applied to ice (530) to generate a resistive AC having a frequency greater than 1000 Hz in interfacial ice at interface (554). A first electrode (510) and a second electrode (514) proximate to the interface are separated by an electrical insulator (512). An AC power source (520) provides a voltage of about 10 to 500 volts across the electrodes to create the alternating electric field. A portion of the capacitive AC associated with the alternating electric field is present in the interfacial ice as conductivity (resistive) AC, which causes dielectric loss heating in the interfacial ice.

Abstract: A pulse system for detaching ice includes a power supply for applying a high-power heating pulse to the interface between ice and an object such as a cold plate of an ice making system, an ice-container, a heat-exchanger, a refrigerator surface or an airplane wing. Pulse heating may be generated within a metal foil or resistive film disposed upon an object to be deiced, or a capillary tube proximate the object to be deiced. An interfacial layer of ice is melted and the ice is released from the object. A force, for example gravity, pressure of vaporization or mechanical scraping, removes the ice from the object.

Abstract: A pulse electrothermal deicing apparatus comprises at least one complex shape characterized by a thickness profile configured to generate uniform power per unit area to melt an interfacial layer of ice. A method of optimizing thicknesses of complex shapes for a pulse electrothermal deicing system includes assigning initial estimates of the pulse electrothermal deicing system parameters. A temperature distribution, a temperature range and a refreezing time produced by a deicing pulse are modeled. Shape thicknesses are adjusted according to the temperature range, deicing pulse parameters are adjusted according to the deicing pulse, and the modeling and adjusting is repeated until the temperature range and the refreezing time are within predetermined limits.

Abstract: Systems and methods for pulse electrothermal and heat-storage ice detachment. A pulse electrothermal ice detachment apparatus includes one or more coolant tubes, and optionally, fins in thermal contact with the coolant tubes. The tubes and/or fins form a resistive heater. One or more switches may apply electrical power to the resistive heater, generating heat to detach ice from the tubes and/or the fins. A freezer unit forms a heat-storage icemaking system having a compressor and a condenser for dissipating waste heat, and coolant that circulates through the compressor, the condenser and a coolant tube. The coolant tube is in thermal contact with an evaporator plate. A tank, after the compressor and before the condenser, transfers heat from the coolant to a heating liquid. The heating liquid periodically flows through a heating tube in thermal contact with the evaporator plate, detaching ice from the evaporator plate.

Abstract: A method for controlling a coefficient of friction between an object and ice includes steps of (1) pulsing power to an interface between the object and the ice to melt an interfacial layer of ice at the interface and decrease the coefficient of friction, (2) facilitating refreezing of the interfacial ice at the interface to increase the coefficient of friction; and (3) repeating steps (1) and (2) to control an average coefficient of friction between the object and the ice. A slider having a surface intended to interface with ice or snow includes a power supply for generating power. The slider also has a heating element that converts power to heat at the surface, the heat being sufficient to melt interfacial ice at the interface, and a controller for controlling delivery of power to the heating element to control friction between the slider and the ice or snow.

Abstract: A system and method for deicing power transmission cables divides the cable into sections. Switches are provided at each end of a section for coupling the conductors together in parallel in a normal mode, and at least some of the conductors in series in an anti-icing mode. When the switches couple the conductors in series, an electrical resistance of the cable section is effectively increased allowing self-heating of the cable by power-line current to deice the cable; the switches couple the conductors in parallel for less loss during normal operation. In an alternative embodiment, the system provides current through a steel strength core of each cable to provide deicing, while during normal operation current flows through low resistance conductor layers. Backup hardware is provided to return the system to low resistance operation should a cable overtemperature state occur.

Abstract: A pulse system for detaching ice includes a power supply for applying a high-power heating pulse to the interface between ice and an object such as a cold plate of an ice making system, an ice-container, a heat-exchanger, a refrigerator surface or an airplane wing. Pulse heating may be generated within a metal foil or resistive film disposed upon an object to be deiced, or a capillary tube proximate the object to be deiced. An interfacial layer of ice is melted and the ice is released from the object. A force, for example gravity, pressure of vaporization or mechanical scraping, removes the ice from the object.

Abstract: A heat exchanger for exchanging heat between gasses such as air and a liquid or gaseous coolant has narrow spacing between exchanger surfaces for high efficiency. To avoid undue obstruction of gas flow due to ice buildup on the exchanger surfaces, the heat exchanger is equipped with sensors to monitor the gas flow and an actuator that widens the spacing between exchanger surfaces such that gas flow remains unimpeded. Embodiments provide for defrosting of the exchanger surfaces when an limit on spacing of exchanger surfaces is reached, and for relaxing the spacing to the original narrow spacing when defrosting is completed.

Abstract: Cost efficient, lightweight and rapid windshield deicing systems and methods are disclosed. The systems utilize step-up converters or inverters, or dual-voltage batteries, to provide a voltage high enough to deice a windshield in less than thirty seconds.

Abstract: Systems and methods for pulse electrothermal and heat-storage ice detachment. A pulse electrothermal ice detachment apparatus includes one or more coolant tubes, and optionally, fins in thermal contact with the coolant tubes. The tubes and/or fins form a resistive heater. Apparatus applies electrical power to the resistive heater, generating heat to detach ice from the tubes and/or the fins. A freezer unit forms a heat-storage icemaking system having a compressor and a condenser for dissipating waste heat, and coolant that circulates through the compressor, the condenser and a coolant tube. The coolant tube is in thermal contact with an evaporator plate. A tank, after the compressor and before the condenser, transfers heat from the coolant to a heating liquid. The heating liquid periodically flows through a heating tube in thermal contact with the evaporator plate, detaching ice from the evaporator plate.

Abstract: A method for controlling a coefficient of friction between an object and ice includes steps of (1) pulsing power to an interface between the object and the ice to melt an interfacial layer of ice at the interface and decrease the coefficient of friction, (2) facilitating refreezing of the interfacial ice at the interface to increase the coefficient of friction; and (3) repeating steps (1) and (2) to control an average coefficient of friction between the object and the ice. A slider having a surface intended to interface with ice or snow includes a power supply for generating power. The slider also has a heating element that converts power to heat at the surface, the heat being sufficient to melt interfacial ice at the interface, and a controller for controlling delivery of power to the heating element to control friction between the slider and the ice or snow.

Abstract: Systems and methods for pulse electrothermal and heat-storage ice detachment. A pulse electrothermal ice detachment apparatus includes one or more coolant tubes, and optionally, fins in thermal contact with the coolant tubes. The tubes and/or fins form a resistive heater. One or more switches may apply electrical power to the resistive heater, generating heat to detach ice from the tubes and/or the fins. A freezer unit forms a heat-storage icemaking system having a compressor and a condenser for dissipating waste heat, and coolant that circulates through the compressor, the condenser and a coolant tube. The coolant tube is in thermal contact with an evaporator plate. A tank, after the compressor and before the condenser, transfers heat from the coolant to a heating liquid. The heating liquid periodically flows through a heating tube in thermal contact with the evaporator plate, detaching ice from the evaporator plate.

Abstract: A method modifies friction between an object and ice or snow. The method utilizes a heating element to apply a pulse of thermal energy to an interface between the object and the ice or snow; the first pulse is sufficient to melt an interfacial layer of ice at the interface. Water forming the interfacial layer refreezes to form a bond between the object and the ice or snow. The steps of the method may be repeated to form a second bond between the object and the ice or snow.

Abstract: A first electrode is separated from a second electrode by an interelectrode space. The interelectrode space does not exceed 3 mm, and preferably does not exceed 100 ?m. Liquid water fills the interelectrode space, thereby electrically connecting the first electrode and the second electrode. A power supply, preferably low-frequency AC, is connected to the first and second electrodes, generating a current through the water in the interelectrode space. The applied electric power prevents freezing of a thin liquid water layer in the interelectrode space, thereby preventing ice formation.

Abstract: Systems and methods for thermally modifying an ice-to-object interface. One system includes a power supply configured to generate a magnitude of power. The magnitude of the power is sufficient to melt an interfacial layer of ice at the interface; typically the interfacial layer has a thickness in a range one micron to one millimeter. A controller may be used to limit the duration in which power supply generates the magnitude of the power, to limit unneeded heat energy dissipation into the environment. Modulating the pulsed heating energy to the interface modifies a coefficient of friction between the object and the ice.

Abstract: Systems and methods for thermally modifying an ice-to-object interface. One system includes a power supply configured to generate a magnitude of power. The magnitude of the power is sufficient to melt an interfacial layer of ice at the interface; typically the interfacial layer has a thickness in a range one micron to one millimeter. A controller may be used to limit the duration in which power supply generates the magnitude of the power, to limit unneeded heat energy dissipation into the environment. Modulating the pulsed heating energy to the interface modifies a coefficient of friction between the object and the ice.

Abstract: A system for modifying ice adhesion strength of ice adhered to an object comprises a composite coating containing wire electrodes covering the surface to be protected. In one embodiment, a composite coating contains electrode wires and insulator fibers. The composite coating is applied to the surface of an object on which the ice adhesion strength is to be modified. The electrode wires are connected to a dc bias source, and they function as cathodes and anodes alternately. The source generates a DC bias to an interface between the ice and the surface when the ice completes the circuit between anode and cathode wires. In another embodiment, a wire mesh is disposed on an electrically conductive surface of the object an opposing DC biases are applied to the mesh and the surface. In another embodiment, the coating has anode and cathode wires woven by insulator fibers as a composite cloth applied to the surface to protect the surface from ice.