State-of-the-art in microreaction technology: concepts, manufacturing and applications

Löwe, Holger; Ehrfeld, W.

doi:10.1016/s0013-4686(99)00071-7

Cited by 212 publications

(117 citation statements)

References 5 publications

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“…Such results have been discussed in terms of a high surface area/volume ratio (A/V) of a microchannel or liquid/liquid interface produced in a channel. 3,4,[14][15][16][17] As an example, since the A/V ratio of a microchannel is very large compared to that of a conventional glass vessel, the surface properties of the channel themselves influence the product yield/selectivity of a chemical reaction. In the present case, however, the channel dimension is not small enough to influence the reaction yield.…”

Section: Knöevenagel Reaction In Polymer Microchannel-microheater Chipmentioning

confidence: 99%

An Application of Plastic Microchannel-Microheater Chips to a Thermal Synthetic Reaction

et al. 2004

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Section: Knöevenagel Reaction In Polymer Microchannel-microheater Chipmentioning

confidence: 99%

An Application of Plastic Microchannel-Microheater Chips to a Thermal Synthetic Reaction

et al. 2004

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“…Due to this, WEDM offers an alternative technology to obtain structural and dimensional accuracies in the miniature die-and moldmaking applications (Uhlmann et al 2005). Since, WEDM technologies apply to micromanufacturing technological applications (Löwe & Ehrfeld 1999). This is especially due to thermal material removal mechanism, allowing an almost all stress/force-free machining independently from the mechanical properties of machined material.…”

Section: Introductionmentioning

confidence: 99%

Parametric optimization of MRR and surface roughness in wire electro discharge machining (WEDM) of D2 steel using Taguchi-based utility approach

Manjaiah

Laubscher

Kumar

et al. 2016

Int J Mech Mater Eng

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Background: This paper reports the effect of process parameters on material removal rate (MRR) and surface roughness (Ra) in wire electro discharge machining of AISI D2 steel. Findings: The wire electro discharge machining characteristics of AISI D2 steel have been investigated using an orthogonal array of design. The pulse on time and servo voltage are the most significant parameter affecting MRR and surface roughness during WEDM process. The simultaneous performance characteristics MRR and surface roughness was optimized by Taguchi based utility approach. The machined surface hardness is higher than the bulk material hardness due to the repetitive quenching effect and contained various oxides in the surface recast layer. Methods: The experiments were performed by different cutting conditions of pulse on time (T on ), pulse off time (T off ), servo voltage (SV) and wire feed (WF) by keeping work piece thickness constant. Taguchi L 27 orthogonal array of experimental design is employed to conduct the experiments. Multi-objective optimization was performed using Taguchi based utility approach to optimize MRR and Ra. Results: Analysis of means and variance on to signal to noise ratio was performed for determining the optimal parameters. It reveals that the combination of Ton3, Toff1, SV1, WF2 parameter levels is beneficial for maximizing the MRR and minimizing the Ra simultaneously. The results indicated that the pulse on time is the most significant parameter affects the MRR and Ra. Concludions: The melted droplets, solidified debris around the craters, cracks and blow holes were observed on the machined surface for a higher pulse on time and lower servo voltage. Recast layer thickness increased with an increase in pulse on time duration. The machined surface hardness of D2 steel is increased due to the repetitive quenching effect and formation oxides on the machined surface.

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“…Microstructured reactors (MSR) are systems with a welldefined structure of channels with an internal diameter in the range of 10-500 m (Löwe and Ehrfeld, 1999). Due to the small diameters of the channels and the high specific surface area of MSR (in the order of 10, 000-50, 000 m 2 /m 3 , Jähnisch et al, 2004), high heat transfer performance can be achieved with heat transfer coefficients up to 25, 000 W/(m 2 K) (Ehrfeld et al, 2000).…”

Section: Introductionmentioning

confidence: 99%

Liquid–liquid two-phase flow patterns and mass transfer characteristics in rectangular glass microreactors

Dessimoz

Cavin

Renken

et al. 2008

Chemical Engineering Science

373

255

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The flow of two immiscible fluids was investigated in rectangular glass microchannels with equivalent diameters of 269 and 400 m. Deionised water, dyed toluene and hexane were selected as probe fluids. Flow patterns were obtained for Y-and T-junction of two micro-channels and monitored by a photo-camera. Volumetric velocities of water and organic phase varied between 1 and 6 ml/h. The formation mechanism of slug and parallel flow was studied and the mass transfer performances of two flow patterns were compared. The shape of the interface between the immiscible liquids was controlled by a competition between the viscous forces and the local interfacial tension. The flow patterns could be correlated with the mean Capillary and Reynolds numbers. The mass transfer coefficients for parallel and slug flow were determined using instantaneous neutralisation (acid-base) reaction. The two flow patterns showed the same global volumetric mass transfer coefficients in the range of 0. 2-0. 5 s −1 , being affected mainly by the base concentration in water for parallel flow and by the linear velocity in the case of the slug flow.

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State-of-the-art in microreaction technology: concepts, manufacturing and applications

Cited by 212 publications

References 5 publications

An Application of Plastic Microchannel-Microheater Chips to a Thermal Synthetic Reaction

An Application of Plastic Microchannel-Microheater Chips to a Thermal Synthetic Reaction

Parametric optimization of MRR and surface roughness in wire electro discharge machining (WEDM) of D2 steel using Taguchi-based utility approach

Liquid–liquid two-phase flow patterns and mass transfer characteristics in rectangular glass microreactors

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