高溫熔融爐心物質落於低溫的液體產生淬冷的現象，其對於核能電廠嚴重事故的管理非常重要。本研究探討高溫熔融物質於去離子水或海水中的淬冷現象。本研究初期以銅顆粒做為熔融物質，以不同次冷度的去離子水或海水進行實驗。研究發現以海水為冷卻水的氣夜介面的蒸氣膜比去離子水有明顯粗糙的波紋。此外，淬冷後沉積於底盤的銅料在較低的次冷度冷卻水中，其表面也較為光滑。但熔融銅之淬冷基本上不會導致碎裂(fragmentation)現象。後續參考文獻改以三氧化二鉍及三氧化鎢的粉末(以下均簡稱BTOP)，以不同BTOP熔體溫度(1000℃及890℃)進行高溫熔體的淬冷實驗，顯示碎裂的現象非常明顯，890℃時的碎片尺寸大於1mm的比率明顯地高於1000℃者；在1000℃下之淬冷可看到熔體四周有碎片雲的產生，而890℃明顯沒有此現象。不同冷卻水淬冷是本實驗之重點，以海水為冷卻水，碎片尺寸大於1mm之質量分率明顯較多。反之，海水淬冷較沒有細微碎片。再由場發射電子顯微鏡(SEM)觀察於海水及去離子水的碎片表面情況，相較於去離子水中，於海水中的碎片表面明顯地較為粗糙，可能是因為海水中有許多離子，而形成zeta電位勢讓熔體與海水緊緊抓住而無法形成完整蒸氣膜，在與海水接觸的區域將有劇烈的沸騰現象。故於海水中的熔體能較快固化，而能保持較高比率的大尺寸碎片。在比較熔融銅及熔融BTOP的淬冷情況及兩者物質特性，可發現由於銅的表面張力遠大於BTOP以及BTOP的比熱遠大於銅，兩者都將使BTOP於淬冷時更容易破碎，與實驗的現象一致。

The quenching of molten corium in the coolant in crucial for the management of severe nuclear accident. The objective of the present study is to investigate the quenching phenomenon of high temperature molten materials in de-ionized water or sea water. At first, cooper particles was employed as the simulated molten material. The experimental results reveal that, in sea water, the interface between water and vapor is very wavy. However, it is quite smooth in de-ionized water. Moreover, the surface of the solidified copper after quench is smoother than the coolant at high sub-cooling that at low sub-cooling. It is also found that there is no or very little fragmentation effect.
So we use to more closely simulate molten corium, through literature review, Bismuth trioxide and Tungsten trioxide powder (BTOP) was subsequently used as the molten material. To study the superheat effect of molten BTOP on the quenching, the BTOP is heated to 1000℃ or 890℃, respectively. Fragmentation effect become apparent for the caucusing BTOP as the simulation. For the case of 1000℃, there is fragment cloud surrounding the melt stream, but it is absent for the case of 890℃ . On the other hand, it is also of significant importance to investigate the quenching phenomena in different coolant, i.e. de-ionized water and sea water. Significant different two-phase flow phenomena in present between the two fluids. Moreover, the mass accumulation distribution of fragment also demonstrates significant difference. The fraction of big fragments in the sea water is significantly more than that in the de-ionized water. The examination of the images of High Resolution Thermal Field Emission Scanning Electron Microscope (SEM) on the fragment surface also shows significant difference. In the sea water, the particle surface is rough and presents a lot of particles with different size, while it is smoother in the de-ionized water. The many ions in the sea water may create the zeta potential effect, like that between solid surface and sea water, resulting in significant contacts between liquid coolant and molten BTOP.

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