Heat exchanger

A heat exchanger, comprising:

• a plurality of heat exchange pipes arranged in sequence along a preset direction, wherein each of the plurality of heat exchange pipes is a flat pipe and each of the plurality of heat exchange pipes comprises a first pipe segment and a second pipe segment which are connected with each other;
• the first pipe segment is provided with a preset bending line, and the preset bending line is perpendicular to the preset direction;
• an included angle is defined between a plane where a flat side of the first pipe segment is located and a plane where a corresponding flat side of the second pipe segment is located, and after the first pipe segment being bent along the preset bending line, adjacent two first pipe segments corresponding to adjacent two of the plurality of heat exchange pipes are capable of being in contact with each other;
• the heat exchanger is used as a microchannel heat exchanger, the heat exchanger comprises two second pipe segments, and the first pipe segment is located between the two second pipe segments;
• two torsional pipe segments are respectively disposed between the first pipe segment and the two second pipe segments to connect the first pipe segment and the two second pipe segments, and each of the two torsional pipe segments comprises two torsional portions and a bending portion, one of the two torsional portions is connected to one of the two second pipe segments, the other of the two torsional portions is connected to the first pipe segment, and each of the two torsional portions is formed by twisting with a preset angle relative to a corresponding second pipe segment;
• the bending portion is located between the two torsional portions and formed by bending with a preset bending radius;
• along the preset direction, the plurality of the heat exchange pipes are inserted in front and back at the first pipe segment, and the bending portion of each of the two torsional pipe segments comprises a front arc part with a radius denoted as R and a rear arc part with a radius denoted as r, wherein, the radius R of the front arc part and the radius r of the rear arc part satisfy the following relationship:
• R>r, and 5.5t≤r≤25t, wherein t is pipe thickness of the two second pipe segments of the heat exchange pipe.