The experimental work aims at investigating the influence of surface roughness on heat transfer by using different nozzles. Part of the rough surfaces are provided directly by the industry. These surfaces of casting products possess considerable roughness up to millimeters which can be either unstructured or with typical grooves in the casting direction. The understanding of its effect on cooling hot metals can help to shed light on the quenching process encountered in the industrial applications. This study will initially be carried out with individual nozzles, such as full cone and full jet nozzles, in order to identify the basic relations. Subsequently, a mold is also applied which can be regarded as a series of full jet nozzles. As for the experiments with mold, the plate is moving downwards with a preset velocity; meanwhile, the plate is fixed for experiments with full jet and full cone nozzle.

实验工作旨在研究表面粗糙度对使用不同喷嘴的传热的影响。部分粗糙表面由工业直接提供。铸造产品的这些表面具有高达毫米的相当大的粗糙度，该粗糙度可以是非结构化的，或者在铸造方向上具有典型的凹槽。了解其对冷却铁水的影响有助于了解工业应用中遇到的淬火过程。最初将使用单个喷嘴（例如全锥形喷嘴和全喷嘴）进行这项研究，以便确定基本关系。随后，还施加模具，该模具可被视为一系列全喷嘴。至于模具的实验，平板以预设的速度向下移动；与此同时，