Any performance advantage to using short or long nozzle on Stihl BG86?
- Thread starter 6012HD
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I realize how sensitive two strokes are regarding sealed crankcases,and crank shaft pulses for proper operation and also I read somewhere that some two stroke blowers(Stihl?) will hardly run with just the nozzle removed,so I thought maybe the length of the nozzle had some effect on the blower performance...maybe not?! Thanks,6012HD
Prob just a comfort thing if you are talking about the tube length.
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For user comfort, I prefer the long tube on my BG86. For blowing leaves, I prefer the flat nozzle over the round nozzle. The flat nozzle gives more velocity. The round nozzle gives more volume.
I bought one of those for my pops, It didn’t have multiple nozzles. He didn’t want the weight of my backpack blower but man using the handheld is painfully slow.
TBS
I have chainsaws and chainsaw accessories.
Nozzle length is for convenience and conditions, the longer nozzle helps if things are a little wet.
canecreekcoffee
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Short nozzle blasts the air in a wider dispersion. Also makes it easier to blow next to houses, walls, etc. Longer nozzle is more powerful but in a more narrow area before it disperses.
Jacob LeClair
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Short answer= long tube bad
Long answer
Let's break it down:
When using a leaf blower, the air flow rate (CFM - Cubic Feet per Minute) and velocity are influenced by the length of the tube.
Physics Behind It
- **Air Friction**: As air moves through a tube, it experiences friction with the tube's walls. The longer the tube, the more surface area there is for this friction, which slows down the air.
- **Pressure Drop**: Longer tubes cause more significant pressure drops. Think of it like squeezing water through a hose; the longer the hose, the less pressure at the end.
- **Air Velocity**: Shorter tubes offer less resistance, which keeps the air moving faster (higher velocity). Longer tubes slow it down due to added resistance.
### Calculations
In fluid dynamics, we use the **Bernoulli Equation** and principles of **Laminar Flow** to understand these effects. A longer tube increases the frictional forces and reduces the kinetic energy of the air, translating to a lower exit velocity.
The trade-off is between CFM (volume) and velocity (speed). Ideally, leaf blowers are designed to balance these for effective use. Adjustments in tube length change this balance, impacting the blower’s efficiency.
Long answer
Let's break it down:
When using a leaf blower, the air flow rate (CFM - Cubic Feet per Minute) and velocity are influenced by the length of the tube.
Physics Behind It
- **Air Friction**: As air moves through a tube, it experiences friction with the tube's walls. The longer the tube, the more surface area there is for this friction, which slows down the air.
- **Pressure Drop**: Longer tubes cause more significant pressure drops. Think of it like squeezing water through a hose; the longer the hose, the less pressure at the end.
- **Air Velocity**: Shorter tubes offer less resistance, which keeps the air moving faster (higher velocity). Longer tubes slow it down due to added resistance.
### Calculations
In fluid dynamics, we use the **Bernoulli Equation** and principles of **Laminar Flow** to understand these effects. A longer tube increases the frictional forces and reduces the kinetic energy of the air, translating to a lower exit velocity.
The trade-off is between CFM (volume) and velocity (speed). Ideally, leaf blowers are designed to balance these for effective use. Adjustments in tube length change this balance, impacting the blower’s efficiency.
