Gas Turbine Engines for Model Aircraft by Kurt Schreckling gives a practical and theoretically sound design procedure for radial compressor. Since a turbine is basically reverse of compressor, you can get a good and easy to comprehend methodology from there, with a little imagination. Here is the book

http://www.amazon.com/gp/product/0951058916?ie=UTF8&tag=rcairplanewor-20&linkCode=as2&camp=1789&creative=9325&creativeASIN=0951058916

Dear,

Start from the cycle analysis, determine the parameters like turbine inlet pressure, temperature, expansion ratio etc... based on your power capacity requirement. from there onwards based on your size requirement decide the geometrical parameters... you can refer my paper of ASME.

Radial turbine is in close similarity with centrifugal compressor. You can say mirror image. If you know the power you can calculate the outer tangential speed of rotor. If this turbine powers a compressor say in turbo/ super charger, you already know rotational speed, so evaluate inner (maximum) diameter. Geometrical proportionality between outer and outer(small) mean diameter of rotor defines such mean diameter. Also empirical formulae can provide geometry of exducer. Outer diffuser if available also has its empirical relations.

Kindly please Refer to my book:

Aircraft propulsion and gas turbine engines

Taylor& Francis/ CRC press, Feb 2008

It includes a completer chapter for design of radial turbines

To my surprise, there are some videos in YouTube about 'Turbine design' some coming from Universities in India, below please find a link to one, and from this, you probably may access others in the list of 'Related videos', hope it's what you were looking for.

http://youtu.be/w2dVCbzzY0Q

As stated in other question in ResearchGate, the patent database 'Espacenet' may contain many patents related to the subject, entering in advanced search as subject / title / abstract: 'Radial Turbine', some will come in

http://worldwide.espacenet.com

I liked the paper "Modelling and CFD analysis of a miniature radial turbine for distributed power generation systems', author Kiyarash Rahbar, ICAE 2013, july 2014, Pretoria, South Africa

Sorry ! july 2013.

Dear Negreanu,

Please send me a copy of this paper.

I can't, because is covered by ICAE @copyright. But you may ask the corresponding author to send it to you: [email protected]

 I had an invitation from TB:  'Tech Briefs Media Group', a SAE International Company, arriving to my e-mail account as: 'NASA Tech Briefs', for watching a free On demand webinar entitled: 'Design and Optimization of Turbomachinery using NUMECA CFD', the speaker is Alain Demeulenaere, from NUMECA CFD.Hope you find it useful. I guess I received this invitation because I purchased SAE papers in a repeated way, but for sure you may find the way to this at the www.sae.org site.

Salud †

I've found this by serendipity, perhaps following the thread would yield more

1987

R.A. Strub, H. Simon et al:

Influence of the Reynolds Number on the Performance of Centrifugal Compressors

ASME-Gas Turbine Conference, Anaheim, California, 1987, Paper-No. 87-GT-10 and in the Transactions of the ASME-Journal of Turbomachinery, October 1987

H. Simon:

Design Concept and Performance of a Multistage Integrally Geared Centrifugal Compressor Series for Maximum Efficiencies and Operating Ranges 

ASME-Gas Turbine Conference, Anaheim, California, 1987, Paper-No. 87-GT-43

Salut +