| Abstract | U radu je za potrebe ispitivanja ultrazvučnog mjerila protoka provedeno usporedno mjerenje volumnog protoka ultrazvučnom metodom i gravimetrijskom metodom na gravimetrijskoj mjernoj liniji u Laboratoriju za procesna mjerenja Fakulteta strojarstva i brodogradnje u Zagrebu.
Na početku kao uvod kratko su definirani pojmovi volumnog i masenog protoka, te je dan okvirna podjela različitih mjerila protoka. Nakon uvoda detaljnije je opisan princip ultrazvučne metode mjerenja volumnog protoka, te dvije ultrazvučne metode najčešće korištene u industriji metoda mjerenja vremena prolaza i metoda mjerenja frekvencijskog pomaka. Sljedeće je bio opisan princip magnetno - induktivne metode mjerenja volumnog protoka. Nakon ove dvije metode opisana je i gravimetrijska metoda mjerenja protoka, te su kratko objašnjenje statička i dinamička metoda mjerenja. Kako je ispitivanje vršeno u Laboratoriju za procesna mjerenja dan je opis mjernih linija koje se nalaze u laboratoriju. Ultrazvučno mjerilo protoka koje je ispitivano u radu je isto detaljnije opisano uz preporuke za instalaciju ultrazvučnih mjerila protoka.
Nakon teoretskog dijela opisana je priprema i provedba usporednog mjerenja ultrazvučnim mjerilom protoka i gravimetrijskom metodom. Rezultati mjerenja prikazani su tablično i grafički, nakon čega je provedena procjena mjerne nesigurnosti metodama tipa A i B. Izračunata je proširena mjerna nesigurnost rezultata obje metode mjerenja, koja je isto prikazana tablično i grafički. |
| Abstract (english) | In this paper, for the purpose of testing the ultrasonic flow meter simultaneous flow rate measurement using ultrasonic measurement method and gravimetric measurement method was conducted using the gravimetric measuring line located in the Laboratory for Process Measurement of the Faculty of Mechanical Engineering and Naval Architecture in Zagreb.
Firstly, as an introduction, brief definitions of volume and mass flow rate, with a short overview of various flow meters, were given. Secondly, after the introduction, the principle of ultrasonic measurement method of volume flow rate was described in more detail. Two ultrasonic measurement methods commonly used in the industry, transit time method and the frequency shift method, were also described. Following, the principle of electromagnetic measurement method was described. After the overview of those two methods, gravimetric measurement was also decribed, including brief explanations of static and dynamic methods. Considering that the testing of ultrasonic flow meter was performed in the Laboratory for Process Measurement, descriptions of measuring lines located in the said laboratory were given as well. Furthermore, as the subject of this paper, the ultrasonic flow meter was described with stated recommendations for the installation.
After the theoretical part, the preparation and implementation of simultaneous ultrasonic and gravimetric measurements were given. The measurement results were shown in tables and graphs, and the standard uncertainty using type A and type B evaluation methods was calculated. In the end, the expanded uncertainties for the results of both methods were calculated and shown in tables and graphs. |
