Investigation of the inner diameter measurement method for wax casting based on response surface methodology

Wind tunnel nozzles are used to accelerate and enlarge airflow within wind tunnels to simulate high-speed fluid environments. This study proposes a wax casting-based method for measuring the inner diameter of spun wind tunnel nozzles, aiming to address the limitations of existing measurement techniques for complex inner geometries. Response Surface Methodology (RSM) was employed to optimize and analyze experimental data, investigating the effects of cooling time, casting temperature, and mold preheating temperature on the shrinkage rate of the wax pattern during the casting process. The experimental results indicate that the wax pattern exhibits the lowest shrinkage rate when the cooling time is 8.6 minutes, the casting temperature is 78.9 °C, and the mold preheating temperature is 50.1 °C, with an average shrinkage rate of 6.382%.