RLV-TD

Reusable Launch Vehicle-Technology Demonstrator (RLV-TD)

India’s first winged body aerospace vehicle, called the Reusable Launch Vehicle-Technology Demonstrator (RLV-TD) was successfully launched from ISRO’s first launch

pad in Sriharikota 80 km off Chennai on the east coast at 7.00 am on Monday. The RLV-TD shuttle shaped like an aircraft was launched aboard the HS9 a seven-meter rocket with a booster, weighing 17 tons with nine tons of solid propellants. The rocket and shuttle made a successful flight of 91.1seconds and the burnout of HS9 followed.

The development of reusable launch vehicle has opened new gateways in conducting space experiments using conventional rockets. One major significance of reusable vehicle is its cost effectiveness. The new vehicle has the potential to cut down the actual cost of launching the rocket by ten times.

With the launch of reusable launch vehicle India has demonstrated the world that what India is capable of. Even though the launch vehicle is just a prototype, there is lot to be done in developing a fully fledged space shuttle.

In this flight, critical technologies such as autonomous navigation, guidance & control, reusable thermal protection system and re-entry mission management have been successfully validated.

With this successful mission India has joined the elite club of space-faring nations. The other countries are the USA, Russia and Japan, that developed and used RLVs for their space missions. This mission has enabled ISRO to successfully collect data and validate such critical technologies and systems as hypersonic speed, autonomous navigation, guidance and control, reusable thermal protection system, powered cruise flight using air-breathing propulsion and re-entry mission management. According to experts, the reusable vehicle technology will reduce the costs of launches in the future by 80% percent.

ESE-17 - Sample Paper

Model questions in General Studies & Engineering Aptitude for Engg. services examination - 2017

http://www.upsc.gov.in/exams/Rev_Syllabus/ese/2016/Model_Q_Paper_ESE_2017_GS_Enggg.pdf

Differences between Bernoulli and S.F.E.E. ?

Well, Bernoulli's equation is a very simplified form of the actual energy equation derived by using control volumes around the fluid flow considering all possible variations including time and space. 

1) Bernoulli's equation doesn't account for any other form of work or energy other than potential energy, kinetic energy and pressure energy. For example, the fluid can flow through a pump doing work on it or a furnace heating a column of air. In these cases, you can't use the simple Bernoulli equation, as points before the area where work is being done on the fluid  and points after it have different Bernoulli's constants.

2) Moreover, Bernoulli's equation between two points is valid along a streamline only. This is because different streamlines have different Bernoulli's constant (although, this is rare and is not true when the flow is irrotational) 

3) For energy equation to be valid, the flow field need not be incompressible or non-viscous as is needed for Bernoulli's equation (unless you are using compressible Bernoulli flow equation and also adding the friction head to take care of viscous effects at the wall)

4) Further, the Bernoulli equation is generally used for steady and laminar flow. Energy equation written in its full glory takes care of variations in viscosity, density, pressure and velocity variation with respect to time and space. Written along with Navier Stokes equation, even turbulence can be accounted for.