Injection temperature is an important factor affecting injection pressure. The barrel of the injection molding machine has 5 to 6 heating sections, and each raw material has its own suitable processing temperature (for the detailed processing temperature, please refer to the data provided by the material supplier). The injection temperature must be controlled within a certain range. If the temperature is too low, the plasticization of the melt will be poor, which will affect the quality of the molded parts and increase the difficulty of the process; if the temperature is too high, the raw materials will be easily decomposed. In the actual injection molding process, the injection temperature is often higher than the barrel temperature, and the higher value is related to the injection rate and the properties of the material, up to 30 °C. This is due to the high heat generated by the shearing of the melt through the injection port. There are two ways to compensate for this difference in mold flow analysis, one is to try to measure the temperature of the melt when the melt is injected into the air, and the other is to include the nozzle in the modeling.