Questions tagged [amateur-rocketry]
Questions regarding model and/or high-powered rocketry.
59
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4
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Spring release system 2.1m long rocket with a weight of 20kg
We have been searching for a trustworthy source to help us design the recovery sytem for a rocket which is going to fly 2600m high with a weight of 22.6kg in the beginning and 17kg in the end (at the ...
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1
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What should be the fuel mass of a hypersonic (Mach 7) rocket using APCP fuel that would deliver a 50 gram payload?
Well, I used this rocket calculator besides asking ChatGPT and BingGPT and both gave me similar answers where the amount of fuel would be around 300 to 4000 grams of APCP fuel. And 30 to 100 grams for ...
- 163
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2
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151
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Need clarification of units on rocket nozzle equation
I have been working on modeling liquid rocket engines and have read the book How to Design, Build and Test Small Liquid Fuel Rocket Engines, I had a question about the nozzle area and the units ...
- 13
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0
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How to calculate the tank boost system for the displacement feed system?
There is a liquid rocket engine running on two components: highly concentrated hydrogen peroxide and kerosene, fuel vapor is ...
3
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3
answers
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Commercial Sources of variable thrust Rocket Engines [closed]
The project is to build a model rocket to take off and land vertically. Max height perhaps 100 feet.
Looking for a suitable engine which can provide variable thrust control and thrust vectoring which ...
7
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2
answers
633
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Why sugar is not commonly used as fuel in hybrid rocket engine?
Hybrid rocket engine usually used rubber or plastic as fuel but why not sugar? Just like many amateur solid rocket motors used sugar. What are the advantages of using rubber in hybrid engine over ...
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1
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334
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Chamber Pressure and Burn Rate equations
I know that chamber pressure is
$$P_0=p \left[ 1+ \frac{1}{2}(k-1)M^2 \right]^\frac{k}{k-1}$$
where $M$ is exit Mach number and according this equation
$$M= \sqrt{ \frac{2}{k-1} \left[ \left( \frac{...
- 41
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1
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How do you calculate thrust produced by a rocket engine?
I was planning on building a water-powered rocket. I also wanted to know how high my rocket might go. Could someone help me figure out, how to calculate thrust produced by a rocket engine?
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Rocket equation with Drag factor
For the
avg Thrust of 2 kN,
burn time = 3.5 s,
burn rate= 1.4,
over the time diff of
dt = 0.1 sec
Isp = 140 sec
Cd for the Ogive nose cone C-section = 0.75
Cross-sec Area of the ogive nose cone = 0....
- 347
3
votes
2
answers
569
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Calculating the projectile of rocket using RCS to tilt the flight path
If I have main solid rocket with 800 N Thrust, 9 kg in total and has RCS thrusters 0.5 m from the center mass. Mid flight the RCS with 1 N force is activated for 2 sec. How does it affect the flight ...
- 347
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0
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Do fins with slightly different masses but the same surface area affect the stability of a rocket?
Each of four fins of a rocket are of slightly different masses like( 0.204, 0.2, 0.199 and 0.19 kg). If they have the same surface area, will that severely affect the stability (spin) during flight? I ...
- 347
3
votes
1
answer
344
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The thrust in the calculation of specific impulse
In calculating the specific impulse using the thrust generated as one of the parameters, do we take the total thrust generated or the average thrust over the period of the burn?
$I_{sp} = \frac{F_{...
- 347
0
votes
1
answer
120
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Tilted exhaust gases from the rocket nozzle after sonic boom [closed]
Our solid propellant rocket, on test, produces sonic boom. Right after, the plume of exhaust tilts sideways. This will definitely have a gimbal effect during flight. The propellant chamber has one ...
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1
answer
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Why are my empirical and theoretical value of mass flow rate in solid propellant rockets not similar?
For a rocket of:
fuel mass $m_f$ = 6 kg,
Thrust = 3.1 kN, (vs 4k using reducing catalyst to delay burn time)
total powered burn time, $t_b$ = 3.5 s, (using reducing catalyst vs 1.8 sec)
This ...
- 347
0
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1
answer
211
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Mass production rate vs mass consumption rate in solid rockets
Do the two terms mean the same? mass production rate, mass flow rate and mass consumption rate in a solid propellant rockets.
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