汽車煞車碟盤轉折處與支撐處尺寸對熱效應之分析

Effect of dimensions of the hat and the slot in a vehicle brake disc on the thermal performance

陳仕瀚(Shi-Han Chen)

指導教授 ： 黃元茂

國立臺灣大學/工學院/機械工程學研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.02102

摘要

本研究分析當汽車碟式煞車改變碟盤支撐處厚度與轉折處溝槽之半徑深度時，所產生之熱效應；碟盤溫度分布、變形與應力之影響。利用煞車碟盤摩擦生成熱量之方程式與動能轉換產生熱能之方程式，建立三度空間有限元素碟盤模型，模擬真實摩擦狀態時接觸面所產生熱的情況，再以此計算所得之熱，與其他的輸入邊界條件於有限元素模型，以研究煞車之碟盤與蹄塊因作用時產生之熱對其應力、變形與應變之影響。用支撐處厚度與溝槽半徑或深度相關之支撐處高度，對碟盤外徑至支撐處內側之尺寸作無因次化，由結果可知，若厚度增加1 %，溫度上可降低0.04 %，變形量可減少0.01 %。當溝槽半徑或深度上增加1 %，溫度上可降低0.5 %，變形量上可減少0.29 %。增大轉折處溝槽半徑或深度，降低溫度與變形量比改變支撐處尺寸之效益大，而增大溝槽半徑為6 mm之碟盤的溫度較原型可降低約攝氏30度，變形量上可減少0.086 mm，偏轉角可減少37.5 %，最大周向應力減少7.1 MPa。

關鍵字

煞車 ； 碟盤 ； 熱效應

並列摘要

This study analyzes the thermal effects of a vehicle brake disc with various thicknesses of the hat and depths of the slot. Convective heat transfer coefficients of brake disc surfaces are calculated, and thermal effects during the brake operation are simulated by using a three-dimensional finite element model. Effects of design parameters including dimensions and boundary conditions on the temperature, deformation and stress distribution of the brake disc are investigated. The effect of the slot depth on the deformation of the brake is more significant than that of the hat thickness. With the length from the inner radius of the hat to the outer radius of the disc as the base, non-dimensional temperature decreased are presented for changing the thickness of the hat and depth of the slot. Increasing 1 % of the hat thickness lowers 0.04 % of the temperature and 0.01 % of the deformation. Increasing 1 % of the slot depth decreases 0.5 % of the temperature and 0.29 % of the deformation that. Increasing the slot depth to 6 mm decreases the maximum temperature of the disc about 30 , the deformation about 0.086 mm, the coning angle about 37.5 %, and the hoop stress about 7.1 MPa lower than these of the original disc and the disc with various thicknesses in the supporting portion.

並列關鍵字

brake ； disc ； thermal performance

參考文獻

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