| 摘要 |
<p>Provided is a heat exchanger that can efficiently perform heat exchange between heating water and combusted gas passing through heat exchanging pipes. The heat exchanger comprises: a plurality of heat exchanging pipes through which the heating water passes, the heat exchanging pipes having a flat tube-shaped cross-section with an open end; first and second fixing plates having pipe insertion holes that are longitudinally spaced at a uniform distance from one another, both ends of each of the heat exchanging pipes being fitted in the pipe insertion holes; first and second parallel passage caps fixed respectively to the first and second fixing plates and closing both the ends of the heat exchanging pipes to form parallel passages; a heating water inlet connected to the first parallel passage cap; and a heating water outlet connected to any one of the first and second parallel passage caps. A plurality of convex parts or concave parts is formed in a certain pattern on surfaces of the heat exchanging pipes. The convex parts or concave parts formed in plurality on neighboring heat exchanging pipes are in point contact with one another.</p> |
