增压锅炉变负荷条件下对流管束传热特性研究

Study of the Heat Transfer Characteristics of the Convection Tube Bundles of a Supercharged Boiler Under Load Variation Conditions

变负荷热力计算是增压锅炉研制的关键。在增压锅炉变负荷热力计算时对关键性能参数的选定是非常关键的，它决定计算精确度，本研究将从增压锅炉炉内空气和烟气特性入手，分析不同负荷下过量空气系数的选取、烟气的流动特性及对流受热面传热特性的分析．通过这些研究，将对增压锅炉负荷变化时热力性能有一个更好的了解，为变负荷热力计算提供了理论依据。

Marine supercharged boilers constitute the main power plant of a ship and their loads are changing with time during the navigation of the ship. Therefore, the load variation thermal calculation is a key to the development of the supercharged boiler and provides a definite theoretical basis for the design and operation of the boiler in question. When a load variation thermal calculation of the supercharged boiler is being conducted, the choice of some performance parameters is decisive, which can determine the calculation precision. Proceeding from the in-furnace air and flue gas characteristics of the supercharged boiler, the authors have analyzed how to choose the excess air ratio at different loads and also the flow characteristics of flue gases as well as the heat transfer characteristics of convection heating surfaces. Through these studies, the thermal performance of the supercharged boiler during its load variation can be better understood, thus providing theoretical data for load variation thermodynamic calculations.