To produce a domain-specific dataset, GPT-4 is assigned the role of an engineering design expert. Furthermore, the ontology, which signifies the design process and design entities, is integrated into the prompts to label the synthetic dataset and enhance the GPT model's grasp of the conceptual design process and domain-specific knowledge. Additionally, the CoT prompting technique compels the GPT models to clarify their reasoning process, thereby fostering a deeper understanding of the tasks.