Optimal abrasive mass flow rate for rock erosion in AWJ machining

0533249 - ÚGN 2022 RIV CH eng C - Conference Paper (international conference)
Jandačka, Petr - Ščučka, Jiří - Martinec, Petr - Lupták, M. - Janeček, Ivan - Mahdi Niktabar, Seyed Mohammad - Zeleňák, Michal - Hlaváček, Petr
Optimal abrasive mass flow rate for rock erosion in AWJ machining.
Advances in Water Jetting. Cham: Springer, 2021 - (Klichová, D.; Sitek, L.; Hloch, S.; Valentinčič, J.), s. 81-90. ISBN 978-3-030-53490-5. ISSN 2195-4356. E-ISSN 2195-4364.
[International Conference on Water Jet 2019 - Research, Development, Applications /6./. Čeladná (CZ), 20.11.2019-22.11.2019]
R&D Projects: GA MŠMT(CZ) LO1406; GA ČR GA18-25035S
Institutional support: RVO:68145535
Keywords : AWJ * erosion * rock material * erosion model
OECD category: Civil engineering
https://link.springer.com/chapter/10.1007/978-3-030-53491-2_9

Erosion process of the Abrasive Water Jet (AWJ) machining on a rock material depends on various parameters. A brittle rock material is removed predominantly by the deformation wear. Abrasive grains can enhance the machining since their hardness and therefore material removal is better than work of pure water. However, to this day, determination of an optimal dosage of the abrasive matter entering into the mixing chamber was rather neglected. Based on the laws of conservations of momentum and energy combined with some empirical facts, it is possible to derive an equation for erosion of the material and subsequently another relation that provides estimation of the optimal mass flow rate of an abrasive matter. The main equation for erosion consists of six experimental coefficients, for an intensive AWJ only four, describing the effectivity of the water jet kw and abrasive jet ka impacting the material. It seems that the energy that is used for erosion is very small and the ideal dosage of the abrasive material is approximately Ṁa ≈ ṁw·(1 − 2kw/ka), where Ṁa and ṁw are the abrasive and water mass flow rates. Such an equation could be used for setting of AWJ machines. The economical optimum (eo) for cutting is proposed via the relation eo = E/Emax − R/Rmax, with the erosion E and its maximum value and the resistivity R and its maximum value.
Permanent Link: http://hdl.handle.net/11104/0311702