Patent ID: 8807446

Claim:
A heating device comprising: a housing including: an inlet formed on one surface of the housing and an outlet formed on an opposite surface of the housing, wherein a coolant flows freely through the housing from the inlet to the outlet, and; a start-up heater and a shut-down heater within the housing and provided in parallel on one side of the housing in a direction perpendicular to a coolant flow direction; and a plurality of heaters within the housing configured to heat coolant provided in parallel on the other side of the housing in a direction perpendicular to the coolant flow direction, each heater being tubular in shape, wherein cross sections in the coolant flow direction of each of the respective heaters change periodically along the longitudinal direction of the heater so as to cause a flow disturbance, and the width of the cross sections is periodically increased and decreased along an inside surface and an outside surface of each tubular heater to form an irregular flow path along the inside of each of the plurality of heaters within the housing, and wherein the heaters are arranged in an alternating pattern in parallel in the housing, and the heaters are arranged to have a phase difference of 90° in a radial direction in relation to the width of each cross section of the heater, and wherein the heating device is configured to provide a cathode oxygen depletion (COD) function for a fuel cell vehicle.