Cascade block final year project

[Aleck]

Ive chosen the cascade wb as my final year reserch project
I'll be analysing the jet impingement parameters on this block such as the nozzle diameter, jet to wall height, dimple diameter.........etc .
I'll be using the initial design of cascade made by Cathar but without the protruding nozles. This is to ease fabrication an so that i could analyze the effects of crossflow with dimpled walls.

I' ll be analysing it with an experimental bench test and try to simulate it using CFD software.

Each of the parameters stated above will be changed to get different configs
So I'll be making alot of of cascades with diferrent jet configurations

Here is a pic of one of them made by me

[jaydee]

What's all the research for? College class?

[bigben2k]

Actually, the protruding nozzles are a very important part of this waterblock. They make a significant difference, ask JayDee116!

[Blackeagle]

As Ben said, the small nozzles going down into the base pattern of holes is vital.

Without them a pattern of holes in the top alone will allow the individual jets to disrupt the impingement effect of each other. You will get little proper impingement down inside the individual cavitys where it's important to have it. At the base of the cavitys you may well end up with trapped stagnant water heating up.

[Aleck]

Originally posted by jaydee116
What's all the research for? College class?

for my first degree final year project..
majoring in CAD/CAM..

[Aleck]

Originally posted by Blackeagle
As Ben said, the small nozzles going down into the base pattern of holes is vital.

Without them a pattern of holes in the top alone will allow the individual jets to disrupt the impingement effect of each other. You will get little proper impingement down inside the individual cavitys where it's important to have it. At the base of the cavitys you may well end up with trapped stagnant water heating up.

i know about the disruption of the jets and it is called crossflow or in other words the flow of the spent coolant after it impinges the heat transfer wall. This is also one of the characteristic of jet impingement that im studying

other than that the protruding nozzles are very hard to be simulated as they are hex in shape ( but not imposible: i have some technical constraints).

and as i change the configuration of the jets how do i get a corelation of the jet diameter and the od (which there is non coz the nozzles are not cylindrical)of the nozzles . this just adds to the complexity of simulation (unless some is willing to help me with a better idea)

for experimental reasons i will be fabricating alot of this blocks with different jet configs ,so its going to be hard for me to fabricate this blocks with different dimensions each time.
But with a confined jet ( jet without protruding nozzles) ill just start of with the longest jet nozzle and smallest diameter and mill off a few mm's to get diferent nozzle lenghts and change to another drill to get a larger diameter

Becaus

[bigben2k]

Well, my original idea had miniature copper tubes, but Cathar opted to mill the jet tubes out of the top.

The inner diameter of the jet tube, should be less than the gap between the outside of the tube and the inside of the cup (aka dimple).

Do you have CFD experience and/or training? (Check out the CFD simulations of my block "Radius", linked in my sig)

[Aleck]

Im planing to use CFX to simulate this block.
Im new to it but I have some of its basics

About the nozzles......

Even if the protruding nozzles are cylindrical , it will add a whole lot more of variables. Such as....

lenght of protruding nozzles
depth of nozzles submerged into cavity
nozzlel thickness
nozzles id
nozles od
different material

This will increase the number of test exponentialy...

I would like to keep it simple to get a good corelation out of those variables

[bigben2k]

Well, that's up to you! Good luck.

Feel free to PM or e-mail me if you have any questions.