On the study of relationships among performance parameter of a muffler
| Autor: | 郭湯淵 |
|---|---|
| Rok vydání: | 2004 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 92 The main purpose of this thesis is to study the relationship and difference among the three methods that are usually utilized to analyze and evaluate mufflers. These methods are namely, Transmission Loss (TL), Insertion Loss (IL) and Noise Reduction (NR). Starting from basic theories, experimental results from all the three methods were compared and analyzed. This thesis discusses the relation of NR and TL, NR and IL, finding out the theory relation among them, and then the experiment is preceded with a simple expansion chamber and probe into the reason of the difference among the experimental result and predicted value. The result of this thesis is pointed out: The predicted TL has great error near the resonance frequencies. Within the range of plane wave, we can increase resonance frequencies by shortening the length of the tail pipe; make it go beyond upper limit frequency of the plane wave to achieve the goal of improving. With the tail pipe of 5cm, the first resonance frequency is changed to 2400 Hz. The predicted IL performs better below the 1490 Hz. Between the comparative performances among Mufflers, we can measure the pressure radiated from one of Mufflers and make the pressure as a datum. Then we can compare the pressure radiated from other Mufflers by the reference-pressure. 【Key word】: Muffler, expansion chamber, Noise Reduction, Transmission Loss, Resonance Frequency. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
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