Vpliv debeline in gostote ivernih in vlakninskih plošč na njihove akustične lastnosti : diplomsko delo - univerzitetni študij

Mravlak, Miha (author), Medved, Sergej (mentor), Bučar, Bojan (reviewer)

Ugotavljali smo, kako velikost iveri in zgradba iverne plošče vplivata na akustične lastnosti. Enoslojne plošče smo izdelali iz frakcij: 6.14-2, 1.5-1, 0.6-0, 0.237-0. Srednji sloj prve večslojne plošče smo naredili iz frakcije 6.14-2 ter zunanjega iz 0.237-0; srednji sloj druge pa iz frakcije 4-2 ter zunanji iz 0.6-0. Testne plošče smo testirali z izolirano testno komoro. Notranjost komore smo oblepili s plamofonom, vpeli zvočnike ter na obod testne komore pritrdili preizkušanec. Na testno ploščo smo pred izvajanjem meritev pritrdili pospeškomer; v oddaljenosti 0,5 m od testne plošče pa postavili mikrofon, in tako izmerili zvočno valovanje, ki je prešlo testno ploščo. Do razlik med posameznimi enoslojnimi ploščami prihaja zaradi praznih medprostorov med delci ter različnih velikosti delcev. Poroznost zelo variira med plosèami, na kar vpliva velikost delcev, ki ploščo sestavljajo. Poroznost vpliva na prehod zvoka med posameznima slojema znotraj plošče. Med sestavnimi delci enoslojnih plošč večjih frakcij je več praznih medprostorov, zato se energija laže absorbira ter pretvori v toploto. Pri ploščah iz finejših frakcij se več zvočnega valovanja odbije nazaj v komoro. Do razlik med posameznima večslojnima ploščama prihaja zaradi praznih medprostorov med delci ter različnih velikosti delcev. Poroznost variira med ploščami, na kar vpliva velikost delcev, ki sestavljajo večslojno ploščo. Hkrati poroznost večslojne plošče vpliva na prehod zvoka med posameznima slojema znotraj plošče.

• Language: Slovenian
• Keywords: iverna plošča, vlaknena plošča, akustika, akustične lastnosti
• Work type: Undergraduate thesis
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: [M. Mravlak]
• Year: 2009
• Number of pages: X, 51 f., [8] f. pril.
• PID: 20.500.12556/RUL-344
• UDC: 630*862.2
• COBISS.SI-ID: 1703305
• Publication date in RUL: 11.07.2014

Secondary language

• Language: English
• Title: Acoustical properties of particle and fibreboard regarding on their thickness and density : graduation thesis - university studies

Abstract

The paper discusses how particle size and texture influence acoustical properties of particle boards. Single layer boards were produced from different particle sizes: 6.14-2, 1.5-1, 0.6-0, 0.237-0. The middle layer of 1st middle layer board was manufactured from particle sizes 6.14-2, and the outer from 0.237-0; the other board had middle layer made from particle sizes 4-2, and outer from 0.6-0. Tests were carried out, with the help of testing chamber. Interior of chamber was covered with sound absorbing foam, and speakers were mounted. On the outer surface of the chamber, the sample with the sample accelerometer was mounted, in a distance of 0.5 m a microphone was positioned to detected sound waves, which went through the board. It was discovered that different particle sizes and free spaces between particles are significant factors for acoustical properties of single layer boards. The particle size has a very important influence on single layer boards, because it determines the porosity of the board. Porosity also has an effect on sound transmission through the board itself. A single layer board made out of larger particles, has free space among particles. These free spaces allow energy to be easily absorbed and converted into heat. In boards from finer particles, more sound pressure bounces back into testing chamber. Particle sizes and variety of free spaces in multi-layer boards dictate differences among multi-layer boards. Particle sizes varying through the multi-layer board also dictate porosity of the multi-layer board. Porosity of the multi-layer board also influences sound transmission between different layers inside multi-layer board.

• Keywords: particleboard, fibreboard, acoustics, acoustical properties