Figure 2 - uploaded by Kenneth S Breuer
Content may be subject to copyright.
Source publication
A new velocimetry system has been developed for use in microdevices that incorporate silicon as their structural material. The system is designed to illuminate and measure particle and surface motions using infrared wavelengths, taking advantage of the fact that silicon is largely transmissive to light with wavelength above 1 μm. The system allows...
Similar publications
Motion detection is very important in video surveillance system especially for video compression, human detection, and behaviour analysis. Various approaches have been used for detecting motion in a continuous video stream but for real-time video surveillance system; we need a motion detection that can provide accurate detection even in non-static...
Moving objects detection and tracking in video stream are basic fundamental and critical tasks in many computer vision applications. We have presented in this paper effectiveness increase of algorithms for moving objects detection and tracking. For this, we use additive minimax similarity function. Background reconstruction algorithm is developed....
The algorithms of autonomous underwater vehicle /AUV/ motion detection and near the bottom stabilization based on stereoscopic images processing are considered in the paper. The approach is based on detection of the same objects on the consecutive frames and their joint displacement calculation. Some results of the real underwater image processing...
Nowadays roads are getting overcrowded, especially in metro cities. Hence the main aim of proposed research is to build a traffic monitoring system which replace or reduce the human monitoring system. The proposed technique is able to detect the movement of vehicles such as cars and to track the moving objects by analyzing a video. Moving object is...
Citations
... Bos et al. 2011). As silicon is semi-transparent (50-60%) to infrared light with wavelengths between 1.1 and 6.0 μ m, it is possible to look into silicon devices using infrared imaging (Chung et al. 2003;Han et al. 2004;Liu et al. 2005). In our prior work (van der Bos et al. 2011), this was done in MEMS printhead at a shortwave infrared (SWIR) wavelength of 1.2 μ m. ...
... Therefore, the particles could not be tracked to measure flow velocities. However, in future work, the DOD frequency could be substantially lowered to decrease the time-averaged flow velocities which potentially allows for particle tracking velocimetry (PTV) or particle image velocimetry (PIV) such as described by Chung et al. (2003); Han et al. (2004) and Liu et al. (2005). When the actuation was halted, the bubbles dissolved, and in the absence of acoustic streaming the dirt particles were trapped in the viscous surrounding, visible at t = 40.67 ...
Piezo-acoustic inkjet printing is the method of choice for high-frequency and high-precision drop-on-demand inkjet printing. However, the method has its limitations due to bubble entrainment into the nozzle, leading to jetting instabilities. In this work, entrained air bubbles were visualized in a micrometer scale ink channel inside a silicon chip of a MEMS-based piezo-acoustic inkjet printhead. As silicon is semi-transparent for optical imaging with shortwave infrared (SWIR) light, a highly sensitive SWIR imaging setup was developed which exploited the optical window of silicon at 1550 nm. Infrared recordings of entrained bubbles are presented, showing rich phenomena of acoustically driven bubble dynamics inside the printhead.
Graphic abstract
Open image in new window
... Although most popular manufacturing techniques offer the possibility to realize transparent windows or sealings, many fluidic devices or components made from silicon or metal do not feature optical access to the fluid flow. In the case of silicon, its transparency in the infrared region can be capitalized upon, so infrared micro-particle image velocimetry can be used to investigate the fluid flow [10][11][12]. ...
Optical flow analysis methods such as particle image velocimetry can only be performed in fluid systems or components with optical access. Many fluidic components, such as metallic tubes, do not typically feature optical accessibility. A new silicone-based molding technique is presented that makes it possible to replicate non-transparent fluidic components as models with optical accessibility that can be used to perform optical flow analysis. Furthermore, to avoid errors due to refraction, a test fluid is presented whose refractive index matches that of the silicone material of the replication. This new method allows flows to be analyzed in tubes or similar components with diameters in the range of only a few millimeters. An initial test was performed demonstrating the proof of concept and the velocity field of the flow inside a manifold was measured using a micro-particle image velocimetry setup. The study showed that both simple parts like tubes and complex parts such as manifolds can be replicated and investigated.
... Burner is the round entry with air and fuel concentric jet ; Uniform layered materials is simplified to the uniform distribution cylinder in furnace [12][13] , as in figure 2 shown. ...
Aiming at the dimethyl ether itself with oxygen, this paper simulate that how much less oxygen quantity Dimethyl ether combustion required than liquefied petroleum gas in the same fuel quantity, and obtain optimum normoxia of dimethyl ether desired. This paper simulated dimethyl ether, liquefied petroleum gas (LPG) combustion with the air for 10%, 20%, 30%, 40%, 50%, 90% Oxygen levels. Under the different oxygen levels, the study found that the best oxygen levels dimethyl ether combustion needed is around 30%, and the best oxygen levels liquefied petroleum gas (LPG) combustion needed is around 50%, so that Oxygen levels dimethyl ether needed is less than liquefied petroleum gas (LPG) needed in the same amount of fuel. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of Kunming University of Science and Technology
... Han et al. [23] first demonstrated an micro-infrared, IR mPIV technique by measuring the velocity field in a micro-nozzle with a 300 mm depth and 40 mm throat width. The solid motion of a micro-rotor was also measured with this infrared diagnostic system. ...
... In this case the IR range would be advantageous for measuring the flow fields in micro-devices (Han et al. [23]; Liu et al. [24]; Franssila et al. [25]; Patil and Narayanan [18]; Golonka [26]; Hardt [27]; Jones [28]). ...
... This material has been widely used to create microfluidic structures and has the added benefit of being optically transparent. Although transparent microfluidic devices are ideal for visual observation, lPIV techniques can be expanded for fluid investigations inside opaque devices, including silicon using infrared illumination (Han and Breuer 2001; Liu et al. 2005) or a wide array of substrates with X-ray illumination ( Kim 2005, 2008b; Kim and Lee 2006). Components and characteristics of a traditional lPIV system are discussed in the following section, starting with volume illumination. ...
... Similar to X-rays, IR lPIV can be applied to measure the velocity profile within silicon microchannels. Conventional tracer particles do not emit and absorb in the IR regime, and the wavelength and tracer particle diameter needs to be chosen to maximize scattering intensity (Han and Breuer 2001). The very high index of refraction of silicon (n = 3.3) will also distort the image. ...
... The very high index of refraction of silicon (n = 3.3) will also distort the image. Therefore, the spatial resolution of IR lPIV is not as good as that of the conventional lPIV (Han and Breuer 2001; Liu et al. 2005). IR lPIV was applied to investigate flow around a heat sink (Jones et al. 2008), and the images were processed with an algorithm that was developed to improve the quality of IR recordings. ...
The development and analysis of the performance of microfluidic components for lab-on-a-chip devices are becoming increasingly
important because microfluidic applications are continuing to expand in the fields of biology, nanotechnology, and manufacturing.
Therefore, the characterization of fluid behavior at the scales of micro- and nanometer levels is essential. A variety of
microfluidic velocimetry techniques like micron-resolution Particle Image Velocimetry (μPIV), particle-tracking velocimetry
(PTV), and others have been developed to characterize such microfluidic systems with spatial resolutions on the order of micrometers
or less. This article discusses the fundamentals of established velocimetry techniques as well as the technical applications
found in literature.
KeywordsMicron-resolution particle image velocimetry (μPIV)-Microfluidics-Particle tracking velocimetry (PTV)-Microchannels
... Data processing of thermal speckle images has been performed not using DIC typical approach but a very similar measurement technique commonly used on fluid flows: Particle Image Velocimetry (PIV). Near infrared imaging technique [6] has been proposed in order to investigate flows inside materials transparent to near infrared but not at visible light. ...
In this paper thermoelaticity and correlation of thermal images are proposed as joint measurement techniques to perform a "full field" measurement of stress and strain on the surface of mechanical components dynamically loaded. Thermoelasticity allow to measure the sum of the principal stress on the surface of a dynamically loaded mechanical component, therefore some researcher proposed the use of data processing methods and combined measurement techniques (using also photoelasticity for example) in order to mesure also the single stress components. Here a new measurement and testing technique, based on the recording of thermal images of a random emissivity pattern and of local thermal fluctuation is proposed to obtain both stress and strain on the specimen surface. Tests has been performed using simple specimen in classical configuration on laboratory testing machines. Results and possibility of this new measurement technique are discussed.
... While they could be useful in low temperature reacting flows found in catalytic systems, they are unable to survive at temperatures associated with most gas phase combustion processes. Breuer [73] took advantage of silicon's transmissivity in the infrared regime to measure velocity using Micro-Particle Image Velocimetry (MPIV). ...
This dissertation investigates the role of heat recirculation in enhancing the flame speeds of laminar flames stabilized in a parallel plate reactor by: (1) developing analytical models that account for conjugate heat transfer with the wall; and (2) making measurements of temperature profiles in a simulated microcombustor using non-intrusive FTIR spectroscopy from which heat recirculation is inferred. The analytical models have varying degrees of complexity. A simple heat transfer model simulates the flame by incorporating a concentrated heat release function along with constant temperature wall model. The next level model accommodates conjugate heat transfer with the wall along with a built in heat loss model to the environment. The heat transfer models identify the thermal design parameters influencing the temperature profiles and the Nusselt number. The conjugate heat transfer model is coupled with a species transport equation to develop a 2-D model that predicts the flame speed as an eigenvalue of the problem. The flame speed model shows that there are three design parameters (wall thermal conductivity ratio (kappa), wall thickness ratio (tau) and external heat loss parameter (NuE)) that influence the flame speed. Finally, it is shown that all these three parameters really control the total heat recirculation which is a single valued function of the flame speed and independent of the velocity profile (Plug or Poiseuille flow). On the experimental side, a previously developed non-intrusive diagnostic technique based on FTIR spectroscopy of CO2 absorbance is improved by identifying the various limitations (interferences from other species, temperature profile fitting, ... etc) and suggesting improvements to each limitation to make measurements in a silicon walled, simulated microcombustor. Methane/Air and Propane/Air flames were studied for different equivalence ratios and burning velocities. From the temperature profiles it can be seen that increasing the flame speed pushes the flames further up the channel and increases the combustors inner gas and outer wall temperatures (measured using IR thermography). The temperature profiles measured are used to make a 2-D heat recirculation map for the burner as a function of the equivalence ratio and burning velocity. The experimental results are compared to the analytical models predictions which show a linear trend between flame speed and heat recirculation.
... Since silicon is quite transparent to wavelengths between 1100 and 2500 nm, a diagnostic technique in the infrared range would be advantageous for measuring subsurface flow fields in silicon microdevices. Han et al. [8] first demonstrated an infrared lPIV (IR lPIV) technique by measuring the velocity field in a micronozzle with a 300 lm depth and 40 lm throat width. The solid motion of a microrotor was also measured with this infrared diagnostic system. ...
... Using tan h % NA/n and Eqs. (8) and (9) gives ...
The flow distribution in a silicon microchannel heat sink was studied using infrared micro-particle image velocimetry (IR μPIV). The microchannel test piece consisted of seventy-six 110 μm wide × 371 μm deep channels etched into a silicon substrate. Inlet and outlet manifolds, also etched into the substrate, were fed by 1.4 mm inner-diameter tubing ports. An image-processing algorithm was developed that significantly improves the quality of IR μPIV recordings in low signal-to-noise ratio environments. A general expression for the PIV measurement depth is presented, which is valid for PIV images that have undergone a threshold image-processing operation. Experiments were performed at two different flow rates: 10 ml/min (Re = 10.2) and 100 ml/min (Re = 102). Little flow maldistribution was observed at the lower flow rate. However, significant flow maldistribution was observed at Re = 102, with the channels near the centerline having an approximately 30% greater mass flux than the channels near the lateral edges of the heat sink. Numerical simulations carried out for flow in the microchannel heat sink agreed very well with the experimental measurements, validating the use of a computational approach for studying the effect of manifold design on flow distribution in microchannel heat sinks.
... However, when the pressure ratio is 2, the flow would spend approximately 80% of its time in Mode 2 and 20% of its time in Mode 1. This issue could be resolved conclusively by using infrared micro-particle image velocimetry [30] to visualize the flow field. Fig. 11 shows experimental measurements of separation factors in two different devices operating with two different gas mixtures: N 2 /SF 6 and Ar/SF 6. ...
... Finally, it would be very useful to verify that the two simulated flow modes are actually realized within the device. This could be accomplished in the present device using an infrared micro-PIV technique that is capable of measuring velocity fields through silicon walls [30]. ...
This paper describes the design, fabrication and characterization of a microfluidic gas centrifuge for separating dilute gas mixtures based on the molecular weights of their constituents. The principal advantage of this approach is its fast response time compared to other methods that are based on permeation or adsorption/desorption. This would allow it to serve as a real-time preconcentrator for improving the sensitivity of miniature chemical sensors. Devices with nozzle throat widths as small as 3.6 μm have been fabricated using photolithography, deep reactive ion etching (DRIE) and silicon-glass anodic bonding. Measurements of the device's performance show that a single stage can achieve a two-fold enrichment of an initially 1% mixture of SF6 in N2 in 0.01 ms. These experimental findings are consistent with the results of two-dimensional numerical simulations of the flow through the device. The simulations suggest that the performance of a single stage could be improved significantly by changing the geometry of the entrance flow. Further improvements in performance could be achieved by cascading the devices.
... Although some bioMEMS devices can be described by coupled PDE's and simulated using existing or emerging multiphysics simulators, many devices have more complicated physics. In devices intended for use in molecular separation, the length scales are such that noncontinuum fluid effects must be considered [48,49,50], and therefore hybrid approaches which combine molecular and continuum models are being developed [55,56,57,58]. For devices used in processing cells, faster techniques are needed for analyzing cells in flow [51,52,53,54]. ...
This short paper, an update of [75], is intended to provide a brief summary and extensive references on biological applications for micro- and nano-machining, as well as the computer-aided design challenges generated by those applications.
