In turbine blade internal cooling the overall thermal performance is:
(Nu/Nuo) / (f/fo)^1/3
where Nu is the Nusselt number for a passage with enhanced cooling. Nuo is a passage with no enhancements.
f is the friction factor with enhancements.
fo is the friction factor with no enhancements...
I'm trying to find the overall friction loss (f) in a complex circuit. I have the pressure losses at each junction and can find "f" in the parallel and series portions of the circuit.
There are two orifices in the circuit.
I know the mass flow rate through the entire circuit, the mass flow...
Air has to turn a corner at the short turn radius and the race car has to turn the corner at the end of the straight away.
If you set up your race car to turn corners at 120 mph it might not perform the same during the race when it has to turn the corner at 250 mph. So, flow the head in as...
28" H2O is about 350 feet per second (~250 mph,average port velocity). The air speed in the short turn will be much higher (up to 700 feet per second).
Most experts seem to agree that Mach .55-.61 (~700 fps)is the maximum velocity you can achieve before a "choke" condition occurs in the port...
There is good infomation on this subject in this technical paper:
A Characteristic Parameter to Estimate the Optimum Counterweight Mass of Symmetric In-Line Engines
Journal of Engineering for Gas Turbines and Power -- July 2004 -- Volume 126, Issue 3, pp. 645-655
Regarding the two MPH data points associated with a typical 1/4 mile timing system, please remember that the velocity timers for the 1/8 mile are placed 66' before the 1/8 mile marker and at the 1/8 mile marker. The MPH is determined NOT at the 1/8 mile lights, but averaged from the two...
The problem that you are having is common. The air speed at the "short side radius" (SSR) is too high and is experiencing flow separation at the SSR.
Try flowing the heads at 36" H20 or even higher. You will here the port begin to "whistle" as the velocity at the SSR reaches the speed of sound...
Here's a basic formula:
84,000 / tuned rpm = runner length
The runner length is measured from the back of the intake valve to the start of the radiused entry of the runner. Most people use the max. torque rpm as the "tuned rpm".
Also, as a general rule of thumb, the port cross section area...
As I recall the Powerglide transmissions come in 25.5" and 28" overall length (I may be a little off on the numbers). The rear extension housing, "rear cone", bolt pattern is the same, so yes you can bolt on the short extension housing on to any aluminum powerglide case.
There are also two...
F1 engineers did testing a few years ago to "try" and determine the limiting factor in an F1 type IC engine.
The information that did "leak out" is that they stopped the testing at 31,000 rpms. I have not seen any other details of the testing made public.
If I recall correctly the intermediate band in a TH400 is for braking and the shift lever MUST be in second gear for it to be effective.
With the shift lever in Drive mode, second gear is accomplished by activating the itermediate clutches AND the intermediate roller clutch. Of course the...
The shape of the intake port, the shape of the combustion chamber, the shape of the piston top, and "fins" in the intake port are common ways to increase "swirl" and "tumble" in the cylinder.
Many cylinder head flow benches are equiped with "swirl" and/or "tumble" meters that measure the...
Consider the dynamic compression ratio instead of the static compression ratio. Dynamic CR takes into account the camshaft timing, rod length, etc.
The dynamic CR will be a better indicator of detonation, idle quality, etc.
We put accelerometers inside 53 ft. trailers and found that the cargo inside the trailer experiences 2.5 to 2.8 vertical g's when traveling over US highways.
Make sure and account for these additional loads in your calculations.
You will need a calibrated orifice plate as a reference to get started.
The one used by Superflow is a thin metal plate (i.e. sqaure edged orifice plate) has one 1.875" hole and one .3125" hole. When you place this plate onto the cylinder head fixture it should flow ~255 cfm.
Several prominent engine builders disagree with the need for swirl and/or tumble at engine speeds above 3-4k rpm.
They (Reher-Morrison, etc.)indicate that at high rpms the fuel/air mixture becomes highly turbulent due to the squish areas of the chamber and heads with zero swirl/tumble can/do...
Whenever you replace the original main cap bolts with studs you should check the main bearing bores. Typically they WILL DISTORT when you change to studs. You should use a dial bore guage to confirm the "roundness" of the bore and have the block honed to correct any problems. Just because the...
