[ScottishBrick]

The low inertia Ti turbines are also, if applicable, of interest. As is the development of ball bearing TD04HL CHRA's from the BMW corner of things.

 

[zak]

Sawa BMW listing for a TD04L-17T today

 

[zak]

This is a 20HF1T Appears to be flank milled. 6+6 but note that the splitter blades don't go up as far through the main blades as say the 20T. Maybe keeps mass closer to the center to help rotor dynamics?

 

[zak]

New compressor wheel 21HR3 Wheel used in a "hybrid" turbo on the very late model Honda Civic Type R, replacing the 20TK3 on the earlier Type Rs. Its a 5+5 design with a huge exducer, 65 mm, makes me wonder if its using TD05H compressor housing and or shafts.

It uses a unique TD04HLL turbine with the second L denoting a longer axial length on the inducer. 9 blade turbine. Kinugawa has come up with their own version for the Volvo, TD04HLL-21H. MHI version Supports 560 hp on a direct injection engine?

Maps:

 

[zak]

21HR3

 

[Austin V70R]

Looks like there may be some similarities to the 22T compressor Wheel geometry : 50.38mm Inducer / 68mm Exducer except that 50% is the blades have been truncated.

Sent from my iPhone using Tapatalk Pro

 

[zak]

Some maps with demand lines plotted - I used S-B's. Don't know what the assumed VE was etc.

First one is 20TK3S or 20TK3S
(seen both notations). S-B is right it needs alot of rpm. TD04H is rated to 190 krpm but that might be with a 14T or 16T wheel not this big wheel.

 

[zak]

This is the 21HR3 wheel. Its a tad large to the demand line but what about its responsiveness its a very large diameter compressor wheel for TD04H, Be great to get one blue light inspect and then underbore (shrink) it a little.

 

[zak]

Here's one I have more than a few hours into studying. 79% efficiency at 14.7 and 20 psi, 76+ efficient at 25 psi. A slight oversize (overbore) of this would be perfect on a 2.3L . . .

 

[zak]

This research group has previously published studies of the TD04HL 19T with Inconel (common) or the TD04HLA titanium aluminide turbine. In this new study they look at combining a TiAl turbine with a magnesium compressor wheel to reduce rotating inertia even futher. Must have one . . . interestingly from this paper there was no benefit in steady state engine efficiency, obviously transient response continues to improve with reduced turbocharger rotating inertia.

Effects of turbocharger rotational inertia on engine and turbine performance in a turbocharged gasoline direct injection engine under transient and steady conditions - Chansoo Park, Motoki Ebisu, Choongsik Bae, 2022 (sagepub.com)

Effects of turbocharger rotational inertia on engine and turbine performance in a turbocharged gasoline direct injection engine under transient and steady conditions
Chansoo Park, Motoki Ebisu, and Choongsik Bae ORCID csbae@kaist.ac.krView all authors and affiliations
Volume 23, Issue 1
https://doi.org/10.1177/1468087420984600

• Contents
  • Abstract
  • Introduction
  • Experimental setup, conditions, and analysis method
  • Results and discussions
  • Conclusion
  • Acknowledgments
  • Declaration of conflicting interests
  • Funding
  • ORCID iD
  • Appendix
  • References
• PDF / ePub
• More

Abstract
The effects of turbocharger (T/C) rotational inertia on engine and turbine performance under transient and steady engine conditions were analyzed in a 2.0 L 4-cylinder turbocharged-gasoline direct injection (T-GDI) engine. The test T/Cs consisted of heavy and light compressor wheels (C/W) and turbine wheels (T/W). The study was conducted in two research stages. First, transient engine load tests were conducted to evaluate the effect of T/C rotational inertia on transient response of the T/C, combustion performance, and fuel consumption. Seconds, steady engine load tests were conducted to find out if a light inertia T/C can run at higher efficiency under the same exhaust pulsating flow conditions within one engine cycle. In order to evaluate the engine on-board turbine instantaneous performances in the units of crank angle degree (CAD), T/C rotation speed and pressure data were measured in the experiment. The instantaneous exhaust gas mass flow rate and the temperature of upstream and downstream of the turbine were extracted by 1-D simulation. Turbine efficiency and mass flow rate parameters were calculated by combining these data. In the results, there existed positive effects of light inertia T/C on response and specific fuel consumption under transient conditions. It was also found that the light inertia T/C could show higher T/C speed fluctuation under the same exhaust pulsating flow conditions. Consequently, blade speed ratio (BSR) and turbine efficiency of light inertia T/C were partially higher than that of conventional one. However, it was not led to higher engine efficiency.

 

[EngTech]

Lighter Wheel will Spin Up Faster , and Blue Printing Manifold will Allow It to Come_Online Earlier then Std Up Grade ..

 

[EngTech]

View attachment 207741
This is a 20HF1T Appears to be flank milled. 6+6 but note that the splitter blades don't go up as far through the main blades as say the 20T. Maybe keeps mass closer to the center to help rotor dynamics?

It's all about the Balancing !