14

With pumping diesel, your main constraint should be safety, not cost. There are very good reasons diesel pumps aren't for sale for $5 on amazon. The main things you want to look at are 1) whether the wetted materials are compatible with diesel (EDPM and silicone for example will dissolve) and 2) how it is grounded. Many pumps can build up static charge ...


9

Since orbiting isn't about altitude, but is instead about velocity (orbiting is the art of throwing yourself at the ground, and missing because you're going sideways so fast), the final goal is to have a heap of lateral velocity so that gravity is merely curving your course, instead of actually pulling you to the ground. The most efficient flight to orbit is ...


6

At a fundamental level, it should be clear that throwing stuff out the back is going to be less economical than sucking in stuff in the front and throwing it out the back faster. For one thing, the former has to carry around a lot of stuff at takeoff. The only possible way to save you from the fundamental issue above is to throw the stuff out the back so ...


5

He refers to Tsiolkovsky's Rocket Equation: $$ \Delta v=v_e \ln {\frac {m_0}{m_f}} $$ where: $v_e$ is the exhaust velocity; ${\frac {m_0}{m_f}}$ is the fraction of mass; $m_f$ - the "dry mass"/"final mass" (rocket without fuel) and $m_0$ - "wet mass"/"launch mass" (rocket fully fueled up.) This equation is one of the most important in rocket science - ...


4

A plane relies on aerodynamic lift to stay airborn. This is much more efficient than using raw vertical thrust like a rocket does. The downside is that planes always need to be moving perpendicular to the direction of gravity. Pretty much all planes except for fighter jets do not have enough thrust to take off vertically. For traveling from point A to B on ...


4

As the rocket is propelled upwards, it expends fuel. So there is no need to carry half empty fuel tanks. By splitting it up into separate stages, you can simply drop off unneeded mass.


4

Economically a rocket engine will always lose out to a jet engine. We'll ignore solid fuel rockets, they are impractical for commercial air travel due to their fixed thrust and inability to turn on and off. A both liquid rockets and and jets need fuel but a rocket engine also needs oxygen, the jet engine pulls this from the air. So for the same amount of ...


4

The answer is that in order to survive and function, the rocket nozzles need to be cooled. How that's done varies with the application, but includes: Liquid Cooling Jacket: The liquid propergols and/or fuels ar circulated through a jacket around the nozzle before being directed to the combustion chamber. This is how the Saturn V F-1 engines and the Space ...


4

First, if you plan to use the same tank for flight and storage, that's not a good approach, because the tank to last without leaking, corroding, or being at risk of damage, needs to be quite thick. Use a dedicated oxygen storage tank (like a gas welding tank), and a small 'flight' tank for the rocket, filled right before launch. It doesn't need to be up to ...


3

Why are you trying to use O2 stored as a gas in a rocket? To get any real quantity of the stuff you would need enormous pressures which argues directly against a light weight tank, the tank structure would weigh more then the gas it contains. The oxygen using rockets all start with liquid oxygen, which has all sorts of fun issues of its own in a small ...


2

To answer the other part of your question, the temperature is that in the chamber, but note that that figure assumes perfect combustion, which may not be the optimum point for specific impulse in your geometry. Many rockets run fuel rich as a reducing atmosphere in the hot bits is easier to cope with then an oxidising one. The largest thermal flux is ...


2

"the fraction of its mass that the rocket loses as it accelerates" means that assuming the power delivered is constant, the total mass of the rocket decreases as the fuel is spent, therefore altering the thrust (power) to mass ratio.


2

Another reason is that each motor stage can be designed for different purposes to match the flights characteristics. So, a relatively short high thrust burn to escape gravity And a longer or continuous burn to accelerate over a course / trajectory Can save weight and complexity so adjustable nozzles are not always needed.


2

In Nuclear Thermal Rockets (NTRs) the heat from a nuclear reaction replaces the chemical energy of the propellants in a chemical rocket. In an NTR, a working fluid, usually liquid hydrogen, is heated to a high temperature in a nuclear reactor and then expands through a rocket nozzle to create thrust. The external nuclear heat source theoretically allows ...


2

From Stardust Generation 1 — bluShift Aerospace: Stardust 1.0 Basic testbed launch vehicle for experiments requiring subjection to the vibrations and accelerations of launch and parachute recovery. Ideal for student and budget payloads. Based upon the mission parameters of the testbed and an altitude of 5000 ft, means they can do it anywhere. Factor in ...


1

Yes, but atmospheric drag is nearly negligable. To get into orbit, the rocket has to expend energy doing several different things, and they each have performance constraints that affect the structural weight of the rocket. Roughly in order of fuel consumption, the rocket has to Gain orbital velocity (a reversible kinetic energy term) Overcome gravity loss (...


1

Vertical-takeoff aircraft do exist. A lot of research has gone into this (mainly in the 1960s), but it all led to one conclusion: there's no commercial case for vertical-takeoff jet aircraft. Only 4 VTOL (vertical takeoff and landing) aircraft have gone into production: the Harrier, the F-35 (B version only), the V-22 Osprey and the Yak-38. These are all ...


1

Disclaimer: I am not professional rocket scientist, information is primarily gathered through internet. This answer is provided with NO warranty. This answer mainly focuses on liquid fuel engines. Pressure-fed Very simple design that does not have pumps. Can be easily started. Chamber pressure (and thus the specific impulse) is very limited compared to ...


1

It isn't really done in 2D. It is done in pseudo 3D. The actual annular areas are factored in. It is primarily based on a uniformity assumption that the gas dynamics are the same all around the nozzle for any constant axial and radial coordinate value. But all the physics are correct for 3D. In the analytic kernel, the uniformity assumption allows you to ...


1

The term is piping and instrumentation diagramm, though plumbing sounds cute. I've never done rocket science so maybe there's conventions I'm not aware of here, but I often work with P&ID in plant design. MS Visio has been used for P&ID drafting (Maybe the 90 day free trial period is enough for your project), there's also the free tool Diag from ...


1

I believe that the Borda-Carnot equation is only valid for incompressible flows, while you mention that the injector orifice is choked. While the flow becomes incompressible pretty quickly after the orifice, at this precise point, it is not. In this case, I think you should use 1D isentropic nozzle theory (wikipedia offers a good start on the topic). If ...


1

Only by increasing the area of the emitter. For a given species, you can't increase the density of the mass flow beyond a certain limit. And that limit decreases if you lower the emitting velocity. What you would need to do gain thrust at constant power, or even constant specific power, would be kick more reaction mass at a lower velocity. If the energy per ...


1

A rocket engine is impractical for 2 reasons As other answers have stated, you must carry the oxidizer on board. More importantly though, a rocket accelerates much faster, burns much more fuel, generates much more thrust because the target velocity is orbital velocity, 9.4 km/sec or mach 27.5 for LEO, or escape velocity 11.2 km/sec or mach 33. A ...


1

To answer first let's look at the different types of "rocket" engines. 1 - Solid Fuel: The issue here is that one a solid fuel rocket is ignited it can't be shut off or throttled very effectively. Imagine the pilot ignites the engine and the aircraft WILL (and I mean WILL) start moving, continue moving and get into the air regardless if he wants to stop. 2 ...


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