Evaluation of Turbulent Heat Transfer Enhancement in Steam-Cracking Furnace Tubes with Modified Internal Textures

乙烯是加拿大化学和塑料工业必不可少的一种有价值的化学产品。它是由乙烷气体和蒸汽在蒸汽裂解炉中在非常高的温度下反应产生的。反应的不希望的副产物是无定形焦炭在反应器壁上的逐渐沉积。这些沉积物降低了炉子的效率，并导致蒸汽裂化过程周期性唐斯以除去焦炭沉积物。增加从反应器壁到炉内流动的气体的传热速率可以降低焦炭形成速率。不幸的是，用于增加传热速率的常规方法也增加了炉中的摩擦压力损失，这转化为更高的操作成本。本研究项目将研究提高乙烯生产炉传热速率的新方法，这些方法只会使摩擦损失增加最小。与Quantiam Technologies Inc.合作，来自UBC Okanagan和阿尔伯塔大学的研究人员将通过在反应堆内壁上放置图案纹理来研究传热增强。纹理突出到湍流边界层中，并改变湍流运动，该湍流运动负责混合气流中的热量和动量。通过使用高保真计算流体动力学模拟和传热和湍流速度场的实验测量，该研究项目将评估各种纹理图案对传热和摩擦损失的影响。该研究将推进湍流传热基础知识的现状。Quantiam Technologies Inc.研究成果的商业应用。将有助于减少与乙烯生产相关的能源需求和温室气体排放。

Ethylene is a valuable chemical product essential to Canada's chemical and plastics industries. It is produced by reacting ethane gas and steam at very high temperatures in a steam cracking furnace. An undesirable by-product of the reaction is the gradual deposition of amorphous coke on the reactor walls. The deposits degrade the efficiency of the furnace and result in periodic shut downs of the steam cracking process to remove the coke deposits. Increasing the heat transfer rate from the reactor walls to the gases flowing inside the furnace can reduce the rate of coke formation. Unfortunately, conventional methods for increasing the heat transfer rate also increase the frictional pressure losses in the furnace, which translates into higher operational costs. This research project will investigate new methods for increasing heat transfer rates in ethylene production furnaces that yield only a minimal increase in frictional losses. In collaboration with Quantiam Technologies Inc., researchers from UBC Okanagan and University of Alberta will investigate heat transfer enhancement by placing patterned textures on the inner walls of the reactor. The textures protrude into the turbulent boundary layer and modify the turbulent motions that are responsible for mixing heat and momentum in the gas flow. By using high-fidelity computational fluid dynamics simulations and experimental measurements of the heat transfer and turbulent velocity field, the research project will evaluate the impact of various texture patterns on the heat transfer and frictional losses. The research will advance the current state of fundamental knowledge of turbulent flows with heat transfer. Commercial application of the research findings by Quantiam Technologies Inc. will help reduce the energy requirements and greenhouse gas emissions associated with ethylene production.