Analysis of Mesamoll-Levamelt mixture for Particle Image Velocimetry

Analysis of Mesamoll-Levamelt mixture for Particle Image Velocimetry

Harshit Malik1, Steffen Jesinghausen2, Sven Pieper3

1Mechanical Engineering, Indian Institute of Technology Bombay,

Mumbai, India

2 Particle Technology Group, University of Paderborn, Paderborn, Germany

3 Particle Technology Group, University of Paderborn, Paderborn, Germany

ABSTRACT: Particle Image Velocimetry is a technique used for flow visualization in two-dimension. The experiment carried out was to determine the optimum matrix fluid concentrations for carrying out the PIV analysis.

KEYWORDS: Flow visualization, tracer particles, laser, optical images, refractive index

1. INTRODUCTION

   Particle Image Velocimetry (PIV) is a flow visualization technique. The fluid is seeded with small tracer particles which are assumed to faithfully follow the flow. The fluid with entrained particles is illuminated and the motion of the tracers is observed to determine the velocity profile of the fluid. PIV is primarily used for two-dimensional flow visualization, though it can be utilized to produce three-dimensional vector fields as well. [1],[2]

   Typical PIV apparatus consists of a camera, a strobe or laser with an optical arrangement to limit the physical region illuminated, the seeding particles and the fluid under investigation. A fiber optic cable or liquid light guide may connect the laser to the lens setup. PIV software is used to post-process the optical images. (Figure 1.1).

   Figure 1.1 Basic Representation of two-dimensional PIV analysis [3]

   The accuracy of the images, obtained from the PIV setup, in representing the actual flow field is highly dependent on the difference in the refractive indices of the fluid and the seeder particles. Thus, it is desirable to have the matrix fluid as transparent as possible.

   For the purpose of PIV analysis in suspensions simulated by Mesamoll-Levamelt-PMMA mixtures, the criteria for optimum transparency need to be ascertained.

2. MATERIALS AND METHODS

   The suspension analyzed was a mixture of Mesamoll, Levamelt and Poly (methyl methacrylate). The PMMA concentration was kept fixed at 25% of the total volume. The volume ratio of Mesamoll to Levamelt was varied from 55:45 to 75:25. For preparing the mixtures, a Rheomix Kneader was used.

   For each concentration, three samples were extracted and the transparency values were recorded at temperatures varying from 50oC to 80oC, using a lux meter. The results are recorded in table 2.1

   TRANSPARENCY PERCENTAGE
   COMPOSITION	TEMPERATURE (°C)
   (%)	50	55	60	65	70	75	80
   55	3.463149	3.446541	3.446826	3.443456	3.405245	3.367131	3.34604
   57	3.237018	3.224319	3.21984	3.227446	3.176819	3.138995	3.108852
   59	2.51675	2.515723	2.526272	2.541296	2.51269	2.488382	2.460822
   61	2.696817	2.679245	2.669189	2.642948	2.571912	2.463033	2.422702
   63	2.784757	2.754717	2.71963	2.681067	2.601523	2.530629	2.49047
   65	3.525963	3.454927	3.32913	3.193562	3.024535	2.881284	2.655654
   67	3.237018	3.215933	3.165195	3.096146	2.973773	2.792564	2.549767
   69	4.061977	4.008386	3.930223	3.782296	3.57022	3.248838	2.858958
   71	4.015913	3.97065	3.896595	3.786531	3.58714	3.286861	2.833545
   73	5.875209	5.794549	5.641026	5.455316	5.152284	4.740177	3.955951
   75	5.40201	5.362683	5.262715	5.133418	4.898477	4.541614	3.867006

   Table 2.1

   The trend observed in the relative transparency values can be analyzed graphically from Figure 2.1 and Figure 2.2

   Figure 2.1

   Figure 2.2

3. CONCLUSION

The transparency values are found to strictly decrease with increase in temperature, keeping the concentration constant. For a fixed temperature, the transparency value is observed to experience a peak in the range of 73-75% relative Mesamoll concentration.

ACKNOWLEDGMENT

I am grateful to Prof. Hans-Joachim Schmid and the University of Paderborn, Germany for providing me with the opportunity and resources to carry out my research work.

REFERENCES

1. http://en.wikipedia.org/wiki/Particle_image_velocimetry

2. Adrian, Ronald J. and Westerweel, Jerry, Particle Image Velocimetry Cambridge University Press, 2010.

3. http://www.fhwa.dot.gov/engineering/hydraulics/research/images/mddot04.jpg