Pneumatic Golf Ball Launcher Designer

Design and optimize your pneumatic launcher with real physics calculations

0 ft

Max Distance

Unit Preferences

Changes are saved automatically

Length:

Pressure:

Mass:

Velocity:

Distance:

Volume:

Saved Configurations

Save and load your launcher setups

Trajectory

Flight Time (s)

Max Height (ft)

Range No Spin (ft)

Range With Spin (ft)

Lock distance scale

Launch

Pressure (psi): 80

Angle: 45°

Barrel

Length: 36"

Chamber

Length: 24"

Spin

Deflection: 0"

Curve Length: 36"

Friction: 0.35

Backspin: 0 RPM

Calculated Results

Muzzle Velocity

                        0
                        ft/s
                    

Maximum Distance

0 ft

Time in Barrel

0 ms

Flight Time

0 s

Max Height

0 ft

Exit Pressure

0 psi

Muzzle Energy

0 J

Chamber:Barrel

0 :1

Seal Efficiency

0 %

Min Effective PSI

20 psi

Valve Efficiency

0 %

Exit Acceleration

0 g

Projectile : Golf Ball

▼

Projectile Type

Diameter (mm)

Mass (g)

Drag Coefficient (Cd)

Type	Diameter	Mass	Cd
Golf Ball	42.67 mm	45.93 g	0.24
Tennis Ball	66 mm	57 g	0.50
Ping Pong	40 mm	2.7 g	0.50
Nerf Dart	13 mm	1.0 g	0.40

Barrel : 1.5" x 36"

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Pipe Type

Nominal Size

OD (in)

ID (in)

Barrel Length (in): 36"

6" 72"

Barrel Volume (in³)

Pressure Rating (psi)

Golf Ball Fit: SDR 21 @ 1.5" has 1.720" ID - provides ~0.040" clearance for a 1.680" golf ball. Ideal for minimal friction while maintaining air seal.

Seal Efficiency: 95% — Excellent seal with minimal blow-by

Chamber : 2" x 24"

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Chamber Pipe Type

Chamber Diameter

Chamber Length (in): 24"

6" 48"

Operating Pressure (psi): 80

20 150

Chamber ID (in)

Chamber Volume (in³)

Chamber Weight (lbs)

Dead Space (valve to ball) (in)

Valve : QEV 1/2"

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QEV Port Size

Valve Type	Size	Cv	Open Time
QEV	1/4"	0.80	3 ms
QEV	3/8"	1.50	3 ms
QEV	1/2"	3.40	3 ms
QEV	3/4"	6.50	4 ms
QEV	1"	10.00	5 ms
Sprinkler (Mod)	3/4"	2.00*	30 ms
Sprinkler (Mod)	1"	3.50*	25 ms
Sprinkler	3/4"	1.50*	55 ms
Sprinkler	1"	2.80*	50 ms

* Sprinkler Cv values are effective values accounting for internal flow restrictions

Barrel Curve & Spin : 0 RPM

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Backspin Mode

Barrel Deflection (in): 0" (straight)

0 6"

Curved Section Length (in): 36" (full)

6" 36"

Friction Coefficient: 0.35

0.1 (slick) 0.8 (grippy)

Calculated Radius:

Calculated Backspin

Manual Backspin (RPM): 2000

0 5000

Active Backspin for Trajectory

Magnus Effect: Backspin creates lift force that extends flight distance. Higher spin = more lift, but also more drag.

Optimization : Zero Exit Accel

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Goal: Zero Exit Acceleration
For maximum efficiency, the projectile should exit when chamber pressure equals atmospheric (~14.7 psi). This means all stored energy has been transferred to the projectile with no wasted pressure.

Optimize Barrel

Adjusts barrel length so the expanding air reaches atmospheric pressure exactly when the ball exits. Longer barrel = more time for air to expand = lower exit pressure.

Optimize Chamber

Adjusts chamber volume to match your barrel. Larger chamber = more air = more energy, but requires finding the right balance for zero exit pressure.

Note: These calculations assume isothermal expansion (slow process). Real launches are closer to adiabatic (fast), which is less efficient. Results are theoretical maximums - actual performance will be somewhat lower.

Valve Flow Comparison

Flow rate comparison at different pressure differentials. QEVs provide significantly faster flow due to larger effective orifice and minimal internal restrictions.

Pressure vs. Velocity

Velocity increases roughly with square root of pressure. Current operating point shown in red.

Pipe Reference Data

Nominal Size	OD (in)	ID (in)	Wall (in)	Pressure (psi)	Projectile Fit

Physics Reference GGDT Comparison Guide →

Core Equations (Adiabatic)

Exit Pressure:
P_exit = P₀ × (V₁/V₂)^γ

Adiabatic Work:
W = P₀V₁/(γ-1) × [1-(V₁/V₂)^γ-1]

Muzzle Velocity:
v = √(2E / m)

Where:
γ = 1.4 (air)
V₁ = chamber + dead space
V₂ = V₁ + barrel volume

Magnus Lift Force

Lift Force:
F_L = ½ × C_L × ρ × A × v²

Spin Factor:
S = ω × r / v

Where:
C_L = lift coefficient ≈ 0.5 × S
ρ = air density (1.225 kg/m³)
A = cross-sectional area
ω = angular velocity (rad/s)
r = ball radius (m)

Valve Efficiency

Transit Time:
t_transit = 2L / v (approx)

If t_transit ≥ t_open:
η_v = 0.5×(t_open/t_transit) + (1 - t_open/t_transit)

If t_transit < t_open:
η_v = t_transit / (2 × t_open)

Cv Factor:
η_cv = min(1, √(C_v/5))

Trajectory

Drag Force:
F_D = ½ × C_d × ρ × A × v²

Where:
C_d = drag coefficient
ρ = air density (1.225 kg/m³)
A = cross-sectional area (m²)
v = velocity (m/s)

Optimal angle: 30-40° with drag

Blow-by / Seal Efficiency

Gap Ratio:
r_gap = (A_bar - A_proj) / A_proj

Flow Competition Model:
η varies by gap regime (0.02-0.40)
Tighter fits → higher efficiency

Threshold Pressure:
P_min = 20 + (r_gap × 80) psi
Below threshold: η² penalty

Where:
A_bar = barrel cross-section
A_proj = projectile cross-section
P = operating pressure (psi)
η = η_base × η_dyn (total)

Effective Energy

Muzzle Energy:
E = W × (A_proj/A_bar) × η_seal

Effective Energy:
E_eff = E × η_valve × η_type

Where:
W = adiabatic work (J)
η_seal = blow-by efficiency
η_valve = valve open fraction
η_type = 0.75 sprinkler, 1.0 QEV