本研究是利用熱管的高導熱特性，應用在機車車燈散熱系統上，並採用田口式直交表實驗計畫法優化，參數設計採用八個合適的設計參數，分別是熱管壓扁厚度、鰭片的數目、鰭片之間距、鰭片之厚度、鰭片之高度、散熱片長度、鰭片上之輻射材質(放射率)、MCPCB尺寸等控制因子，每個因子分別有三個水準做參數設計，調整參數以降低LED車燈中LED之溫度。 選用田口式直交表實驗法的L18(21×37)直交表來設定各組參數值，再利用計算流體力學(Computational Fluid Dynamics, CFD)模擬，求得最後溫度。 初始設計得到T_c溫度為86.17°C，以田口方法之望小特性品質特性分析計算後，得到最佳預測設計因子，以此最佳設計因子以計算流體力學來模擬可得到模擬T_c溫度為76.11°C，LED的溫度明顯有下降，証明此方式可以有效率的改善設計開發流程之時間。 使用其他流體可以進一步降低LED溫度，本研究使用純水取代空氣來當流體與散熱片進行熱交換，求得最佳所需的水量為15公升，此時T_c可以降低至63°C，大大提高了散熱系統的效率。 ;This research using heatpipe in thermal cooling system of motorcycle’s headlight, and executing Taguchi method to analysis. We establish the eight parameters such as the thickness of heat pipe, and number of fins, the pitch of fins, the fin thickness, the height of fin, the heat sink length, the radiation material on heat sink, and the size of MCPCB. After the above eight parameter must be determined. Next, these parameters are divided into three levels separately in order to reduce the Tc that on the MCPCB temperature of LED headlight. By using Taguchi Method makes the optimization of LED headlight cooling system easier whereas the simulation times of the 8 parameters and the 3 levels of each parameter will be in total 4374 times. We establish a product that can effectively reduce simulation times to 18. The Tc temperature of LED headlight is lower than all of probable combination exactly. And using CFD(Computational Fluid Dynamics) to simulate the system finally get the Tc temperature. The original design of cooling system without optimization by Taguchi Method, the Tc temperature of cooling system was 86.17°C. With the optimal optimization design we can reach the Tc is 76.11°C, the temperature of sink and MCPCB was significantly decreased. Moreover the optimization by Taguchi Method design can get the best construction in as short time. Therefore, this research for the cooling components decreases development time and the cost of production. Because use other fluid in this system could decease the temperature of system, so this research take pure water as the cooling fluid contact with the heat sink. Then can get the optimal water volume in this cooling system. It is useful to down the Tc temperature to 63°C.
