| 摘要 |
<p>Disclosed is a variable diameter pipe heat exchanger, comprising a heat exchange pipe (9) and a cold medium disposed in the heat exchange pipe (9). The heat exchange pipe comprises an outer pipe (1) and an inner pipe, the inner pipe comprising a first conduct (2) and a second conduct (3) in communication with the first conduct, and the first conduct (2) having an inner diameter less than that of the second conduct (3). When the cold medium is a high-temperature and high-pressure gas and flows within the first conduct (2), the flow rate is slow, with a longer heat exchange time, due to the smaller diameter of the first conduit (2), and when the cold medium flows within the second conduit (3), since more liquid is present as most of the heat has been conducted away, and liquid generated can flow away more rapidly due to the larger diameter of the second conduit, a situation where most of the area of the heat exchanger is in a low-efficiency condensing state can be avoided. The heat exchanger enables primary heating even at a low power; the length of pipe required in order to make the same heat, at the same temperature, pressure and flow, when a cold medium enters the heat exchanger, is half of that of a conventional heat exchanger. The present heat exchanger can save costs in terms of materials and lead to a decrease in the size of the heat exchanger.</p> |
