Heat exchanger and washing apparatus including heat exchanger

A heat exchanger, comprising:

• a ceramic body included in a heater that has a tubular shape, wherein the ceramic body includes a first end that is open and a second end that is open and opposite the first end along a central axis that defines an upstream direction and a downstream direction;
• a heat element of the heater that extends along the central axis, wherein heat element includes a fourth end that is closer to the second end and a third end that is closer to the first end;
• a lead-out conductor that is connected to the third end of the heat element and extends toward the first end of the ceramic body in the upstream direction;
• a water receiver being tubular and having a fifth end that is open and extends away from the first end of the ceramic body in the upstream direction, and a sixth end of the water receiver that is open and opposite to the fifth end, wherein at least a portion of the water receiver is concentric with a core of the ceramic body along the central axis with the water receiver located inside of the core of the ceramic body;
• a first channel is defined by an inner peripheral surface of the water receiver,
• a second channel that is fluidically coupled in the downstream direction of the first channel and defined by an inner peripheral surface of the core of the ceramic body, wherein the second channel has a larger cross-sectional area than the first channel, and
• wherein at least part of a boundary between the first channel and the second channel is located nearer the second end with respect to the central axis than a boundary between the heat element and the lead-out conductor with respect to the central axis, and
• the boundary between the first channel and the second channel is inclined with respect to the central axis.