一種新型螺旋爪式轉子流體幫浦之設計

Abstract

本論文提出新式螺旋爪式轉子之設計，該設計可應用於流體幫浦。該螺旋爪式轉子設計包含截面輪廓及軸向旋轉。首先，定義爪式轉子之輪廓曲線為其截面，並建立其參數化模型，是以該設計爪式轉子輪廓曲線上之任一點均可由輸入指定參數獲得，且轉子輪廓外形可由設計變數調整。將爪式轉子應用於流體幫浦，其幫浦效率及流量也可藉由此參數化模型求得，意即使用者可依其需求幫浦性能設定轉子之設計變數。考量爪式轉子幫浦在運作過程中產生的周期性振動容易產生噪音及造成機構損壞，將螺旋設計應用於爪式轉子，藉由對軸向各截面進行連續相位移，達到疊合不連續流量的作用，可穩定排放以降低振動。螺旋爪式轉子幫浦之排放為單向，容易造成額外應力作用於幫浦機構，是以本研究提出一改良式螺旋爪式轉子，其弧形之側邊構造可達雙向排放之功效。為能準確評估爪式轉子幫浦及螺旋爪式轉子幫浦運轉時每一瞬間之流量，本研究撰寫一電腦運算程式，對各不同設計之爪式轉子幫浦進行分析，分析結果顯示螺旋爪式轉子幫浦的確可有效穩定排放流量，達降低振動之功效，提升幫浦效率。

This thesis describes the study of an innovative helical claw rotor design for fluid pump. Firstly, the contour of the claw rotor pair is constructed and is set into parametric model, and the design variables which can lead to the required performance, such as flow rate, is determined by the parametric model. By the computer aided design program, the claw rotor model is obtained after inputting values of the design variables. Due to the pulsation problem caused by the discontinuous pumping flow, the helical design is applied to the rotor pair. Helical design can be considered as phase shifting an indefinite number of the cross-sections of the claw rotor pair and superimposing the discharge flow. Therefore, the discharge flow would become more continuous and the pulsation would be decreased. Taken the stress and bending torque caused by the unidirectional discharging flow of the helical claw rotor pump into consideration, the rotor pair which could make a two-way discharging process would be an ideal design. Then a curve-sided type helical claw rotor pair, which is the modification of the helical claw rotor pair, is designed. Next, a calculation program is proposed in order to analyze the performances of these claw rotor pump designs, and the conventional claw rotor pump can therefore be compared with the two helical designs. The analysis shows that the pumping flows of the helical claw rotor pump and the curve-sided type helical claw rotor pump are more continuous than the conventional design, which results in less flow pulsations and higher efficiencies. In conclusion, the helical designs of claw rotor fluid pump are worthy to develop.