Difference between turbines of turbo charger & turbo engine

[blackbird]

Hey Users,

I'm new to this forum and as well as to this field of turbine engines. My background is of reciprocating engine for power generation. As I have been reading a bit about turbine engines lately a question came up in my mind, here it goes:

turbine/ jet engine also has turbine, turbochargers installed in cars or any other engines also has turbine. Difference is that in turbine engines the flow of exhaust gases is in axial direction of turbine, where as in turbocharger the flow of gases is in radial direction. Why this difference is there?
Why turbine engines doesn't have turbine in which angle of attack of gases is in perpendicular direction of the shaft of turbine?

Looking for any kind of input. Thanks a ton in advance.


Regards,
GB.

[racket]

Hi GB

The radial inflow turbine wheel is generally restricted to "small" sizes as its cheaper to produce than an axial wheel and does a great job in a turbocharger , but once the size increases the axial wheel is a better proposition as its lighter in weight and "easier" to produce ............LOL, its more complicated than this , but theres no reason why very large radial turbine wheels can't be used , they were in the very early jet engines , and very small axial wheels are used in the RC micro turbines , its just a case of using the appropriate wheel for the job :-)

Cheers
John

[blackbird]

Thanks John for reply.

I thought that it has something to do with the efficiency of the turbine. Talking about the manufacturing complexity, I feel that radial turbines can be produced in the same fashion as axial ones; using the dovetail locking disc and individual blades.

PS: I'm only talking about the turboprop engines where direct drive/load is given onto the shaft.

Thanks again for your reply, it's just that I love discussing about jet engines....!

[racket]

Hi GB

The radial inflow can generally process a higher pressure ratio than an axial wheel .

Radial wheels start to get very heavy once past a certain size and their axial length gets excessive , also they don't lend themselves to a compact frontal area as well as the axial wheel .

Each has their advantages and disadvantages .

Cheers
John

[blackbird]

Thanks John,

I find this much satisfying answer. They do tend to get heavy after certain sizes, as bigger radial turbine will need a much thicker turbine disc as in contrast to axial turbine's disc... Surely also they can't participate as a low frontal area turbine.... thus rendering them unsuitable for flying applications...

I guess in that case a radial turbine can only find its application in "SMALL" power generation field... I have seen some bigger turbines installed on 4500 HP engines, they also are using axial turbine discs instead.



I'm glad that you replied.... Now I'm quite clear on the point.

CHEERS....