Geoff_H

That's why well designed heat exchangers are contra flow. Hot flows one direction through heat exchanger, cooling fluid the reverse.

In the early days of my career I did lots of work with low pressure airflow including heat exchangers. It was all designed with mathematics, get the older guys to use experience to modify the maths. The measure extensively when commissioning and alter as needed. It was very impirical. The airflow was with furnace airflow. I am sure that aircraft manufacturers go through several interactions of cowling design, I would expect that with any one off design would need redesign, a reason among others that manufacturers charge so much.

The oil cooler was part of it. But there is a lot of similarities between fins and "radiator" flow. Metal cooled by air. Big difference is that the 'radiator' style has to be more complex owing to lower temperature of metal. Yes the Mooney fight was with oil temperatures.

With properly designed inlet I would expect laminar flow in, the inside would then ensure turbulent flow in the heat exchanger (reynolds number drastically increasing) and exiting turbulent. One of the biggest problems is a design that works well at climb out velocities then works just as well a cruise velocities. Mooney used an exhaust duct, its opening size adjustable from the cockpit. Mooney always have temperature issues, it was a constant job to adjust the duct.

One consideration that does not seem to be taken into account in this thread is that lamina flow reduces heat exchanger transfer capability. Laminar flow creates an insulating layer next to the transfer 'metal'. Velocity of fluids at a surface is zero for laminar flow. I was taught that low pressure air acts like a liquid, I also have observed wall attachment at low flows that affects the flow through heat exchangers. I believe that the only way to study this problem is with finite element analysis.

A lot of expensive cars seem to catch on fire in Sydney's south west suburbs. Must be some type of self combustion in that area. Lol

I can't find much information about the KR1B. Are there any in Australia?

Thanks nomad. Much appreciated. I was misguided, but have seen the error of my way. Totally retired now..... well maybe not totally.. lol

I was an engineer but we used the same method to discover a faulty CT. We discovered the RF radiation after an operator said that now that a ct exploded that he could watch tv again...

I actually commissioned the Eraring power station end of the first 500kV power line in Australia.. the scary thing is a 330/500kV switchyard on a wet dark night it crakles and sparks. I worked at Vales Point power station when we had 330kV current transformer explosions.... Very very scary.

The problem very high voltages is the corona discharge. Any sudden change of shape (eg bolts) will create an additional high voltage that can cause a discharge, between phases in this case. The mathematics of corona discharge is the same as a stress raiser on a rotating shaft.

I would like to do that. Looks like Garfly wants to get the crash pictures 😁

Maybe afforfable flying is an oxymoron. I have been trying to make an aircraft design that can be built for under $10k, with access to good metal machines. Not sure that I have enough years left to get it done. I have been using the twin small two strokes a brilliant idea, but as it will never get capable of being RAA it maybe a fruitless effort.

Thanks guys now I understand the 95.10 is for very low performance aircraft. I will have to leave my project in VH category I just hope that my medical holds out by the time it's finished.

Not limited to one engine but just try to get a two engine light aircraft registered with RAA, eg Cri Cri, just can't happen!

I looked into using the jet engines that are used in the cri cri for my cri cri like project. I can't remember the exact endurance either the dual two stroke engine tank. It endurance was less than the monomum. The guy in WA that has put the engines into his cri cri has added significant fuel storage. The engines were designed for model aircraft and had very high fuel consumption.

I don't know about this GT, they are not even considered in power generation, but weight is a big factor with recupetators. The bigger they are the less fluid flow penalties, the smaller they are the higher the gas flow, and consequent efficiency loss. Gas and air losses square as the velocity increased. So a designer, I guess, would pictch recupetators size at cruise power.

Recupetators duct the exhaust gas over the out of the compressor to heat the air and expand the air. Just like a burner would. Not as much fuel is then required to heat this heated air to get the gas (air plus products of combustion) to the maximum first stage turbine blades. Roughly same turbine power, a slight reduction due to exhaust pressure gain from having to pass through the recupetators. Recupetators usually reasonably heavy having to withstand compressor outlet pressure, they also decrease the gas pressure to the turbine.

Cmc coatings of burners have been around over 15 years to my knowledge. I have not seen blading yet ,(retired so out of the loop), but may they have. Both Siemens and GE have ceramic coated burners. Refurbished burners were more expensive than refurbished blades, for 100MW Gt 10M every 3 years of continuous operation (2011 price)

GE were experimentimg with ceramics over 10 years ago. Turbine blades are subject to huge radial forces. With no operational GT yet my money would be that a successful product has not yet been developed. First to do it will make a lot of money. In power generation just a few % improvent in efficiency means big bucks.

Pt6 is a brilliant design. It was designed many years ago. Has a very high bsfc.

What is the weight and bsfc of the RED engine. I can't find a reference to it.

What is an "equivalent gas turbine". The BMW B 58 engine gets 340hp out of 300lb weight....the state of the art (Merc get 400hp out of same ).. but there are many gas turbines less and some more. Modern engines, modern gas turbines are similarly developed. We need to compare similar with similar.

Check out the dates of the original manufacture of the engines in the brake specific field consumption. Of GT and piston increase dramatically as date gets more recent. GT low power very low bsfc are a function of air compressor pressures at low speed. Hence low "compression ratio". I always ran my Mooney at full throttle, landing very much excepted.