High Velocity Nozzle Testing



Using a compression fitting for a nozzleIt's time to continue with testing mixing improvements for the Appleseed. So far the eductor has provent to be very successful at improving mixing, but installing it was anything but simple. It turned out to be a real pain in the backside. Not to mention that commercial eductors that fit our pump choice are nearly nonexistant.

This test is going to be of a compression fitting turned into nozzle. I'm using a 1/4" compression x 1/2" npt adapter. They are commonly available at most hardware stores. The through hole is about a 3/16" dia hole. From previous experiments we got a good stream with about 30psi of head pressure, so it was an ideal starting place.

nozzle adapterIn order to install the compression fitting as a nozzle we need an adapter that has both male and female threads. The male threads are to screw into the tank. The female threads are to accept the compression fitting. This adapter lets us mount the compression fitting just inside the tank on the circulation return line.

The adapter is a 3/4" x 4" schedule 80 pipe nipple with 1/2" female NPT threads tapped in one end. Schedule 80 pipe is thicker than the normal schedule 40 pipe you find in the hardware stores. The extra thickness makes the female threads possible. Other than thickness, the main difference is how they were made. Schedule 40 pipes started as a flat bar that were rolled into a pipe and welded. If you look inside a schedule 40 pipe, you will see a weld line going from end to end. Schedule 80 pipes are cast as a pipe and do not have the weld line.

Schedule 80 pipe nipples are basically special order from your local plumber or over the internet. You can cut the pipe threads with an inexpensive pipe tap or you can let your plumber tap it for you.

As you can see in this image, it makes a good strong stream. The stream will pass through a 1"hole as far as 10 ft away from the nozzle and reaches 16-20 ft in the air.


High Velocity Biodiesel Nozzle

The Test Rig

 I've essentially mounted the pump above in the drum below. Yep, you noticed the fan shround is off the pump. The pump needed a little push to get started.  Looks like I need to replace the capacitor before using it on a processor again.


nozzle test rig


Test Results

The tests went great. The compression fitting made a great nozzle with a strong coherent stream without any modifications. The water in the drum test was in motion and rolling around in the drum. I placed some grass clippings in the drum to track the water movement. and none of the clippings settled out. Without the nozzle, the grass clippings settled out quickly. I am satisfied that the nozzle will do a good job of preventing glycerin from settling during processing and I'm ready to try it in an Appleseed Processor.


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