TY - GEN A1 - Nguyen, Lam A1 - Buhl, Johannes A1 - Bambach, Markus ED - Bambach, Markus T1 - Multi-bead Overlapping Models for Tool Path Generation in Wire-Arc Additive Manufacturing Processes T2 - Procedia Manufacturing; Part of Special issue: 23rd International Conference on Material Forming Y1 - 2020 U6 - https://doi.org/10.1016/j.promfg.2020.04.129 SN - 2351-9789 VL - 47 SP - 1123 EP - 1128 ER - TY - GEN A1 - Nguyen, Lam A1 - Buhl, Johannes A1 - Israr, Rameez A1 - Bambach, Markus T1 - Analysis and compensation of shrinkage and distortion in wire-arc additive manufacturing of thin-walled curved hollow sections T2 - Additive Manufacturing Y1 - 2021 U6 - https://doi.org/10.1016/j.addma.2021.102365 SN - 2214-8604 VL - Vol. 47 ER - TY - GEN A1 - Nguyen, Lam A1 - Buhl, Johannes A1 - Bambach, Markus T1 - Continuous Eulerian tool path strategies for wire-arc additive manufacturing of rib-web structures with machine-learning-based adaptive void filling T2 - Additive Manufacturing Y1 - 2020 U6 - https://doi.org/10.1016/j.addma.2020.101265 SN - 2214-8604 VL - Vol. 35 ER - TY - GEN A1 - Nguyen, Lam A1 - Buhl, Johannes A1 - Bambach, Markus T1 - Decomposition algorithm for tool path planning for wire-arc additive manufacturing T2 - Journal of Machine Engineering Y1 - 2018 U6 - https://doi.org/10.5604/01.3001.0010.8827 SN - 1895-7595 SN - 2391-8071 VL - 18 IS - 1 SP - 96 EP - 107 ER - TY - GEN A1 - Mai, Tam V.-T. A1 - Bui, Thanh Q. A1 - Nhung, Nguyen Thi Ai A1 - Quy, Phan Tu A1 - Shrestha, Krishna Prasad A1 - Mauß, Fabian A1 - Giri, Binod Raj A1 - Huynh, Lam Kim T1 - An Ab Initio RRKM-Based Master Equation Study for Kinetics of OH-Initiated Oxidation of 2-Methyltetrahydrofuran and Its Implications in Kinetic Modeling T2 - Energies N2 - Cyclic ethers (CEs) can be promising future biofuel candidates. Most CEs possess physico-chemical and combustion indicators comparable to conventional fuels, making them suitable for internal combustion engines. This work computationally investigates the kinetic behaviors of hydrogen abstraction from 2-methyl tetrahydrofuran (2MTHF), one of the promising CEs, by hydroxyl radicals under combustion and atmospheric relevant conditions. The various reaction pathways were explored using the CCSD(T)/cc-pVTZ//M06-2X/aug-cc-pVTZ level of theory. The Rice–Ramsperger–Kassel–Marcus-based master equation (RRKM-ME) rate model, including treatments for hindered internal rotation and tunneling, was employed to describe time-dependent species profiles and pressure and temperature-dependent rate coefficients. Our kinetic model revealed that the H-abstraction proceeds via an addition-elimination mechanism forming reaction complexes at both the entrance and exit channels. Eight different reaction channels yielding five radical products were located. The reaction exhibited complex kinetics yielding a U-shaped Arrhenius behavior. An unusual occurrence of negative temperature dependence was observed at low temperatures, owing to the negative barrier height for the hydrogen abstraction reaction from the C-H bond at the vicinity of the O-atom. A shift in the reaction mechanism was observed with the dominance of the abstraction at Cα-H of 2MTHF ring (causing negative-T dependence) and at CH3 (positive-T dependence) at low and high temperatures, respectively. Interestingly, the pressure effect was observed at low temperatures, revealing the kinetic significance of the pre-reaction complex. Under atmospheric pressure, our theoretical rate coefficients showed excellent agreement with the available literature data. Our model nicely captured the negative temperature-dependent behaviors at low temperatures. Our predicted global rate coefficients can be expressed as k (T, 760 Torr) = 3.55 × 101 × T−4.72 × exp [−340.0 K/T] + 8.21 × 10−23 × T3.49 × exp [918.8 K/T] (cm3/molecule/s). Our work provides a detailed kinetic picture of the OH-initiated oxidation kinetics of 2MTHF. Hence, this information is useful for building a kinetic me chanism for methylated cyclic ethers. KW - ab initio KW - RRKM-ME calculations KW - 2-methyl tetrahydrofuran KW - OH radicals KW - kinetic modeling Y1 - 2023 U6 - https://doi.org/10.3390/en16093730 SN - 1996-1073 VL - 16 IS - 9 ER -