PowerPoint Presentation

Lift-off Aerodynamic Characterization of RLV-TSTOGuided by: Ms AMBILY PN

The cost of access to space is the major deterrent in space exploration and space utilisation. A RLV is the unanimous solution to achieve low cost reliable and on-demand space access. ISRO is developing fully RLV technology for TSTO capability. This project deals with the aerodynamic characterisation of RLV-TSTO during its lift-off phase. During Lift-off, the wind can blow in any direction, the aerodynamic loads acting on the vehicle depends on the blockage of wind due to the Umbilical Tower and also on the turbulent wake caused due to it. To study the effect of launch pad on aerodynamic coefficients, tests needs to be carried out with and without the LP using commercially available CFD software.

ABSTRACTTo study the effect of Launch Pad on aerodynamic coefficients. To study the effect of wind on the launch vehicle during lift-off. To study the effect of ground proximity on aerodynamic coefficients.To study the effect of AOA on aerodynamic coefficients

A reusable launch vehicle is the unanimous solution to achieve low cost reliable and on-demand space access. An RLV may be able to offer a new range of services, such as retrieval of satellites from orbit, rapid passenger or package services to many points of the globe, and tourism services that may carry civilians into space for entertainment.Space Transportation is one of the key future Technology for a country like India. A low cost and quick access to the space plays a vital role in determining the domination of Space Industry.ISRO is developing fully reusable launch vehicle (RLV) technology for two stage to orbit (TSTO) capability. Significance of an RLV

Possible TSTO configuration options

The booster stage being sub-orbital, calls for larger range requirement. Considering the range requirement & propellant loading requirement, a winged body configuration is chosen for the booster. The wing body was found to be better option for upper stage due to the lower heating rates and higher aerodynamic efficiency.Hence a re-usable TSTO with both stages as winged body was selected.

RLV-TSTOThe Best Configuration

The first stage will be powered by a semi cryogenic winged booster and re-enters the atmosphere at suborbital velocities to be recovered at a downrange station.The second stage will be cryogenic. It will deliver the satellite into orbit, de-orbit, re enter the atmosphere and land on the runway at SDSC-SHAR like a conventional aircraft.RLV-TSTO vehicle is expected to place 11t payload in 400km circular orbit (LEO).A typical RLV-TSTO mission consists of lift-off, ascent, separation, descent phase and landing. The lift-off aerodynamic characterization of Reusable Launch Vehicle-Technology Demonstrator Vehicle has been done earlier. In a similar sense our project deals with the aerodynamic characterisation of RLV-TSTO during its lift-off phase.

8To Study on the effect of Launch Pad on aerodynamic coefficients. To study the effect of launch pad on aerodynamic coefficients, tests are to be carried out with and without the launch pad. The tests are planned to be done by using commercially available Computational Fluid Dynamics software.

To Study on the effect of ground proximity on aerodynamic coefficients. In order to study the effect of ground proximity on aerodynamic coefficients, tests are to be carried out by varying the height of the model from the launch pedestal. The values of aerodynamic coefficients due to the wind are to be found out when the model is at different height from the launch pedestal. The values are to be taken till the model clears the launch tower. The values obtained must be compared with that of the model alone configuration.

In Our ProjectTo Study on the effect of wind on the launch vehicle during lift-off.To study the effect of wind on the launch vehicle during lift-off, tests are to be carried out by changing the direction of wind from 0 to 360 insteps of 5. During the tests, angle of attack faced by the vehicle is always 90.

To Study on the effect of AOA on aerodynamic coefficientsIn order to assess the effect of angle of attack on aerodynamic coefficients, tests are to be carried out without launch pad for different angles of attack (). The model roll orientation, () is varied from 0 to 90 in steps of 22.5. Effect of angle of attack obtained from these tests are appropriately super imposed on the vertical mounting aero data (with Launch Pad) to generate the final aero coefficients during lift-off phase for different heights of the model from the ground level.

Sign Convention of Forces and Moments

Dimensions of Booster

1D=5400mmDimensions of Orbiter

During the first phase of the project, we have done a detailed literature survey regarding lift-off aerodynamic characteristics of launch vehicles and collected sufficient information and necessary data, including specifications and dimensions of RLV-TSTO. Further we have prepared an action plan to carry out the project in the next semester. Current StatusGeneration of the 3D model of RLV-TSTO in Catia or Solidworks software.Generation of the 3D model of Launch Pad.Analysis of the model in Fluent software to study the variation of aerodynamic coefficients under the presence and absence of Launch Pad.Study the effect of Ground proximity in fluent by varying the height from the Launch pedestal. Chosen heights are

H1- RLV at Launch PedestalThe Next Step

H2- RLV at the Centre of LPH3- Tip of RLV is in the level of LP

H5- Wing region of Booster is out of LP

H4- Wing Region on Orbiter is out of LPValues obtained from the above analysis is to be compared with the values of without LP condition.To study the effect of Side wind on the vehicle during lift-off using fluent software, analysis is done by keeping the model stationary and by changing the direction of wind in steps of 5 from 0-360 (72 iterations will give more accuracy in the result).

[1].Prasath M et al, Lift-off Aerodynamic characterization of a Technology Demonstrator vehicle.[2].Sreenivasulu J et al, Studies on Reusable launch vehicle Two Stage to Orbit Option.[3].Robert M Hall et al, Aerodynamic Characterization of a Modern Launch Vehicle.[4].William G. Tomek et al, Overview of Experimental Investigations for Ares I Launch Vehicle Development AIAA 2011-0013.[5].George W and Moses G, Wind tunnel studies of Ground wind loads on Saturn Launch Vehicles Journal of Spacecraft, Vol.4 No.2, 1967.[6].Arash Naghib-Lahouti et al, Parametric Analysis of Aerodynamic Characteristics of Launch Vehicles with Strap-On Boosters.[7].S K Epuri et al, Aerodynamic Configuration Design of a Reusable Orbiter.[8].Bandu N Pamadi et al, Aerodynamic Characteristics and Development of the Aerodynamic Database of the X-34 Reusable Launch Vehicle.[9].Giuseppe Pezzella, Aerodynamic Design of the Vertical Take-off Hopper Concept of Future Launchers Preparatory Programme.[10].Jaison Joseph et al, Mission Design for a Two Stage To Orbit (TSTO) Fully Re-usable Launch Vehicle.[11].S C Gupta et al, Evolution of Indian Launch Vehicle Technologies.[12].Larry R Clark und John P Decker, Longitudinal Aerodynamic Characteristics of a Model of a Horizontal-Take-Off Reusable Launch Vehicle at Mach Numbers from 3 to 6.[13].Rajeev R Krishnan et al, Reusable Cryogenic Stage for RLV TSTO- Configuration and Challenges.[14].www.currentscience.ac.in-Downloads-article_id_093_12_1697_1714_0.pdf.[15].http://en.wikipedia.org/wiki/File:Indian_carrier_rockets.svgReferences19Jai hind