本研究以更改不同液態金屬加熱器設計對PDMS微流道中的液體進行實驗與模擬的控溫分析，以達到流道中液體溫度均溫的效果。研究將更改加熱器中央寬度以修改加熱器局部電阻分配局部發熱量，並以溫度螢光感測塗料(Temperature Sensitive Paint, TSP)量測微流道內的液體溫度。研究發現在加熱功率0.3 W、雷諾數為1的條件下加熱器中央寬度150 μm的模型中的軸向液溫分布改進長直加熱器受軸向熱傳與共軛熱傳產生入出口處溫度較低的現象，在均溫範圍設定在±0.25 °C或以下會有三種加熱器模型中最佳的均溫表現。若進一步增加中央寬度到200 μm的加熱器則觀察到液溫出現更為明顯的兩個局部最高溫，顯示往液體流道入出口方向補償過多的熱不利均溫表現。
後續討論以加熱器中央寬度150 μm的模型在雷諾數0.1、1和10下的控溫效果比較，結果顯示當雷諾數由0.1升至1時液溫在入口處與出口處分別降低2.1 °C與提升1.1 °C，在中央處則降低0.1 °C，兩雷諾數設定的熱對流效果皆較小，控溫效果相近。而當雷諾數由1升至上升至10會產生沿軸向非線性上升的液溫分布，與雷諾數1相比有不同程度的下降，入口液體溫度差異達11.3 °C，出口液體溫度差則為4.6 °C，均溫效果不佳，因此較不適合控溫。
最後嘗試在模擬中將相變化材料(Phase Change Material, PCM)放置在液體流道的另一側吸收原本將溢散的熱儲存起來，在加熱器關閉時釋放潛熱達到節能效果。在暫態模擬的入口溫度條件為常溫而非實驗入口溫度的條件下，與常開加熱器且沒有PCM的控溫裝置相比減少16.7%使用的能量，平均液溫由穩態的40.1 °C降至單一循環內平均36 °C。因PCM擺放位置距離加熱器較液體流道遠，加熱循環中出現在時間上液溫波動較劇烈，平均液溫差達到8.5 °C，在時間上均溫效果不佳。在本研究中的控溫裝置中加入PCM可減少使用能量但在時間上有較差均溫效果。

The experimental and numerical methods were used to study temperature control analysis of PDMS microchannels by modifying liquid metal heater designs to achieve uniform liquid temperature. The heater design was adjusted by varying its central width to redistribute local resistance and heat generation. Temperature measurements within the microchannel were obtained using temperature sensitive paint (TSP) experiments. Under heating power of 0.3 W and Reynolds number of 1, the heater model with a central width of 150 μm showed improved axial temperature distribution. This design mitigated the lower inlet and outlet temperature observed in a long, straight heater due to axial and conjugate heat transfer, achieving optimal uniformity among the three models within a range of ±0.25 °C. However, increasing the central width to 200 μm resulted in two pronounced local temperature peaks, indicating excessive heat compensation toward the inlet and outlet, which negatively impacted temperature uniformity.
Further analysis compared the temperature control performance of the 150 μm model at Reynolds numbers of 0.1, 1, and 10. Results indicated that increasing the Reynolds number from 0.1 to 1 led to a 2.1 °C decrease in inlet temperature and a 1.1 °C increase in outlet temperature, with a 0.1 °C decrease in the center. The heat convection effects at both Reynolds numbers were relatively small, yielding similar temperature control performance. However, raising the Reynolds number from 1 to 10 resulted in a nonlinear axial temperature increase, with inlet temperature reduction of up to 11.3 °C and outlet temperature reduction of 4.6 °C, indicating poorer uniformity and unsuitability for temperature control.
Finally, phase change material (PCM) on the opposite side of the liquid channel was added in the simulation model to absorb dissipated heat and release latent heat when the heater was turned off to achieve energy savings. Under transient simulation conditions where the inlet temperature was ambient rather than the experimental temperature, the PCM-integrated system consumed 16.7% less energy compared to a continuously running heater without PCM. The average liquid temperature was reduced from the steady-state 40.1 °C to the average of 36 °C within a single cycle. However, due to the spatial arrangement between the PCM and heater, average liquid temperature fluctuations during the heating cycle were more pronounced, with a difference of 8.5 °C, resulting in poorer temporal uniformity. While incorporating PCM in the temperature control system reduced energy consumption, it will have influence on temperature uniformity over time due to the limitation of PCM and heater arrangement in the PDMS microchannel.

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