Week 3

July 1-5

PIV Experiment

We carried out the PIV experiment this week. Here's how this experiment work:

The pipe connects the model to the pump, and the entire circulation is filled with a mixture of glycerol and water (60% glycerol and 40%) water. This liquid has the same index of refraction as silicone, so the ventricle will disappear when the model is filled with liquid. The shiny particles are put into the mixture and move with the liquid in the circulation. The pump will simulate flow that is similar to the flow in the human body, pushing the mixture into the model. The laser emits light with strong energy shines into the model. The highspeed camera can pick up the light reflected from those particles and track their movement. Then we use the computer to process the image we get and find out the velocity of the particles inside the model. The laser we use have strong power, so if you look at the laser without wearing any eye protection, you might get blind.

This picture on the left is taken when the model is half-filled with a water-glycerol mixture. We can see that the bottom half of the ventricle because the light is not refracted between the liquid and the silicone. The top half of the ventricle is still visible due to the air inside.

My own model

I am assigned to build a model by myself! It is simply a straight tube but it is the right difficulty for somone like me that's not familiar with this process.

MRI

Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI applies a very strong magnetic field and aligns the proton "spins". The scanner than pick up the different spin to produce an image about the thing that's being scanned.

One interesting thing that I didn't know about MRI before is that there is a very strong magnet that is inside the machine. This magnet is on even when the machine is not working. So anything that has metal on it is not allowed in the MRI room. The pump we use has to be kept at the control room.

Warning sign about the strong magnet on the door of MRI room.

Hole on the wall between the control room and MRI room so we can connect the pump with the model

Model inside the MRI maching being scaned.