Exercices 4Rockets are usually propelled by ejecting gases from the combustionof a liquid fuel mixture. However, this solution is rather inefficient totransport spacemen to other planets. A proposed solution is to useplasma engines, the VASIMR engines. The gases ejected by theseengines do not come from a combustion but are simply heated by anelectric resistance at high temperature. However, such engines arevery greedy in electricity, it would thus be necessary to install on thespacecrafts nuclear reactors.We consider the following characteristics:Loss of mass due to nuclear reactions A : 5,05 ug/sMass of ejected gas u: 10,1 g/sGas ejection velocity u: 192 m/s1 What is the "source" flow rate qs in kg/s?2 What is the inflow qi in kg/s?3 What is the outflow qoin kg/s?Once in orbit around the Earth, it is necessary, to travel towards Mars,to increase the speed of the rocket of 4,4 km/s. Assuming the variationof mass due to the nuclear reactions negligible, during how manyhours will have to light the engine if the rocket has a mass M of 95tonsWhat is the expression for the total mass of the rocket over time(considering all mass changes)?O. MO ii. M - (u+ A)tO lii. M - utO v. M - (u - A)tO v. M+ t

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Rockets are usually propelled by ejecting gases from the combustion of a liquid fuel mixture. However, this solution is rather inefficient to transport spacemen to other planets. A proposed solution is to use plasma engines, the VASIMR engines. The gases ejected by these engines do not come from a combustion but are simply heated by an electric resistance at high temperature. However, such engines are very greedy in electricity, it would thus be necessary to install on the spacecrafts nuclear reactors. We consider the following characteristics: Loss of mass due to nuclear reactions : 5,05 ug/s Mass of ejected gas u : 10,1 g/s Gas ejection velocity u: 192 m/s 1 What is the "source" flow rate qs in kg/s? 2 What is the inflow qi in kg/s? 3 What is the outflow qo in kg/s?

Rockets are usually propelled by ejecting gases from the combustion of a liquid fuel mixture. However, this solution is rather inefficient to transport spacemen to other planets. A proposed solution is to use plasma engines, the VASIMR engines. The gases ejected by these engines do not come from a combustion but are simply heated by an electric resistance at high temperature. However, such engines are very greedy in electricity, it would thus be necessary to install on the spacecrafts nuclear reactors. We consider the following characteristics: Loss of mass due to nuclear reactions : 5,05 ug/s Mass of ejected gas u : 10,1 g/s Gas ejection velocity u: 192 m/s 1 What is the "source" flow rate qs in kg/s? 2 What is the inflow qi in kg/s? 3 What is the outflow qo in kg/s?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.32P

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