電灸罐的熱傳遞分析

Analysis of Heat Transfer in Electromoxibustion Cup

傳統的灸療法藉由燃燒艾草或藥草產生熱，經由穴位的熱刺激而促成抗病的效果。古老的拔罐是利用罐器加熱進行醫療，須將熱導入罐器或杯器內，再迅速的罩在皮膚上。灸療與拔罐常配合針療同時施做，這些療法具有的共通特性，就是要運用熱。然而，灸療法在施做時會產生煙，造成許多患者呼吸器官的不適；拔罐療法則會存在燒灼皮膚之虞。本論文提出一種利用電熱管加熱的新型電灸罐，具有灸療與拔罐的雙重功效。罐器採用壓克力材質製成，易於加工且可透視皮膚療效狀態，亦可形成近似絕熱的邊界條件。本論文以數值分析電灸罐內的熱傳遞，我們將電灸罐視為加熱源在上方的密閉空問，考量變數包括電熱管的設定溫度（T（下標 o））與室溫（T（下標 ∞））。我們利用高階塗彩及灰階等溫線圖，說明罐器內的熱傳遞狀況。計算結果顯示，在相同的縱橫比（H/D）情況下，在罐器內的溫度幾乎都是沿著軸線方向變化；垂直皮膚方向的熱傳導值（Q（下標 cond））相當小，此意味主要的熱傳遞機構為熱對流效應。

Moxibustion therapy is a traditional Chinese medical technique which applies heat produced from ignited moxa or mugwort herb over the skin to stimulate acupuncture points of the body for the prevention or treatment of disease. Cupping therapy is usually performed by introducing heat into a cup or similar object and placing it immediately on the skin. Moxibustion and cupping therapies are used along with acupuncture therapy. These techniques are characterized by their amazingly rapid attainment of the desired results by the heat. Because moxibustion often includes the burning of moxa or mugwort herb, patients who have respiratoy problems should avoid the use of smoking moxa or mugwort herb. Cupping therapy has a risk of burning the patient if lot carefully executed. In this study, a new electromoxibustion cup is designed. We ca place the cup on the skin and gently heat the air ill the cup with a electroheater An acrylic cup has been used for this purpose, because, one can see the skin within the cup and produce insulated boundary conditions. A numerical analysis is used to study the heat transfer of the electromoxibustion cup. We focused on heat transfer in the electromoxibustion cup, a enclosure heated from the top. The phenomena of natural convection in the enclosure are as varied as the heating temperature (T(subscript o)) and room temperature (T(subscript ∞)). The colorful temperature contours and isothermal lines are simultaneously presented to illustrate heat transfer within the cup. Subject to the same aspect ratio (H/D), the temperature within the cup is found to vary along the axial direction. The heat conduction normal to the skill (Q(subscript cond)) is relatively small; hence, the heat transfer mechanism is dominated by heat convection.