DOCSLIB.ORG

Flow Visualization Studies of VTOL Aircraft Models During Hover in Ground Effect

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Flow Visualization Studies of VTOL Aircraft Models During Hover in Ground Effect NASA Technical Memorandum 108860 Flow Visualization Studies of VTOL Aircraft Models During Hover In Ground Effect Nikos J. Mourtos, Stephane Couillaud, and Dale Carter, San Jose State University, San Jose, California Craig Hange, Doug Wardwell, and Richard J. Margason, Ames Research Center, Moffett Field, California Janua_ 1995 National Aeronautics and Space Administration Ames Research Center Moffett Field, California 94035-1000 Flow Visualization Studies of VTOL Aircraft Models During Hover In Ground Effect NIKOS J. MOURTOS,* STEPHANE COUILLAUD,* DALE CARTER,* CRAIG HANGE, DOUG WARDWELL, AND RICHARD J. MARGASON Ames Research Center Summary fountain fluid flows along the fuselage lower surface toward the jets where it is entrained by the jet and forms a A flow visualization study of several configurations of a vortex pair as sketched in figure 1(a). The jet efflux and jet-powered vertical takeoff and landing (VTOL) model the fountain flow entrain ambient temperature air which during hover in ground effect was conducted. A surface produces a nonuniform temperature profile. This oil flow technique was used to observe the flow patterns recirculation is called near-field HGI and can cause a on the lower surfaces of the model. Wing height with rapid increase in the inlet temperature which in turn respect to fuselage and nozzle pressure ratio are seen to decreases the thrust. In addition, uneven temperature have a strong effect on the wing trailing edge flow angles. distribution can result in inlet flow distortion and cause This test was part of a program to improve the methods compressor stall. In addition, the fountain-induced vortex for predicting the hot gas ingestion (HGI) for jet-powered pair can cause a lift loss and a pitching-moment vertical/short takeoff and landing (V/STOL) aircraft. The increment. tests were performed at the Jet Calibration and Hover Test (JCAHT) Facility at Ames Research Center. Figures l(b) and l(c) show the flow field for a single-jet configuration. The effects of wind (fig. l(b)) and buoyancy (fig. l(c)) bring the hot gases back into the Introduction engine inlets. This recirculation is called far-field HGI. Jet-powered vertical/short takeoff and landing (V/STOL) Multiple-jet configurations may also experience far-field airplanes can experience significant performance losses HGI. As illustrated in figure l(b), far-field HGI can occur during hover and during transition between hover and rapidly when there is a crosswind blowing the hot exhaust wing-borne flight. These losses are caused by the back to the inlet or when the aircraft speed causes a propulsion efflux. Two propulsion-induced effects are similar relative motion between the hot gases and the especially critical during operation near the ground for engine inlet. Depending on the wind speed, aircraft speed, takeoff or landing: (1)jet-induced effects on aero- and aircraft geometry, there is a wind speed which dynamics and (2) hot gas ingestion (HGI) effects on produces a maximum temperature rise. At either greater engine performance. or lesser speeds the temperature rise is reduced because the hot gases from the far field are convected away from HGI is a term used to describe any flow mechanism the engine inlets. However, buoyancy effects (fig. 1(c)) where hot exhaust gas from a propulsion jet returns to the take time to become established. For the AV-8 Harrier, it inlet of the same propulsion system. Three flow patterns takes about 30 seconds in hover for the air around it to that cause HGI in jet-powered V/STOL aircraft are shown heat up by 5°C. This 5°C increase in air temperature in figure 1. Figure l(a) shows the flow field for a entering the inlet reduces the thrust by about 4 percent. multiple-jet configuration in ground effect. The hot jets impinge on the ground and form wall jets which may run Near-field HGI tends to bring hot exhaust gases quickly into each other underneath the airplane and form a into the engine inlets. For the AV-8 Harrier, in about one fountain. This fountain brings the hot exhaust gases very second during hover the fountain effect can increase the rapidly to the airplane's undersurface where they impinge inlet temperature by as much as 10°C. This temperature increase results in approximately 10 percent loss of thrust, forming a lateral stagnation line in the spanwise direction. which is significant considering the fact that the thrust-to- At the side of the fuselage or at the edge of the wing weight ratio for most V/STOL airplanes is only 10 to planform some of the flow continues upward where it 30 percent greater than one. The Harrier, however, does may find its way into the engine inlets. Between this stagnation line and both the front and rear jets, the not represent the worse case scenario for HGI. In some jet VTOL airplane models an inlet temperature rise (ITR) of *San Jose State University, San Jose, California. 55°C has been measured (refs. 1 and 2) after only a very shorttimeinhoverwithingroundeffect.Suchvaluesof the agreement with experimental data which involved ITR can cause a major loss of thrust and consequently a three-dimensional (3-D) models was not very good. This crash. result demonstrated the need to study flow fields around 3-D models to obtain a better understanding of the The HGI problem was recognized (ref. 3) and considered mechanisms which cause HGI. during the research and development of the Harrier in the late 1950s. In the mid 1960s, NASA initiated several The purpose of the present flow visualization experimental projects (refs. 1, 2, 4-7) to obtain HGI data. investigation was to use a simple two-jet geometry to Additional research was done in Europe (refs. 8-10), evaluate the effect of model configuration (fiat-plate or especially for the VAK-191B VTOL aircraft. The recent 3-D model), NPR, and model height on the general flow U.S./U.K. advanced short takeoff and vertical landing patterns which cause HGI. The fiat-plate model was (ASTOVL) aircraft studies have generated a renewed designed to be tested either as a body alone or as a wing- interest in the topic as shown by current experimental body configuration. The 3-D model was designed so that investigations (ref. 11) of some of the basic mechanisms three different airplane configurations could be tested and configuration effects. with minimum hardware changes (body alone, body with high wing, and body with low wing). The flow patterns In the late 1960s and early 1970s, the first attempts were on the lower model surface were observed using a made to develop analytical methods for HGI. An early fluorescent oil flow technique. This report presents the empirical approach by Behnert (ref. 9) was developed in results of that flow visualization study. support of the VAK-191B VTOL aircraft program. This method was based on a correlation of the small-scale model data and the full-scale aircraft data. In 1971, Gray Symbols and Acronyms and Kisielowski (ref. 12) developed an engineering method for predicting the temperatures and velocities in ASME American Society of Mechanical the vicinity of vertical lift engines of jet V/STOL aircraft Engineers operating near the ground. This method described the De equivalent nozzle diameter based on the propulsion efflux flow field starting at the lift jet exit, total area of all exhaust nozzles, in. continuing to ground impingement through the wall jet to either a far-field flow or to a fountain flow back up to the H distance from nozzle exit to ground aircraft and the engine inlets. The effects of both near- impingement point, in. field and wind-generated far-field recirculation were HGI hot gas ingestion included. Barron and Frauenberger (ref. 13) applied this HTR hover test rig analysis in an early code that evaluated jet-induced ground footprint and hot gas upwash characteristics of ITR inlet temperature rise V/STOL aircraft. JCAHT Jet Calibration and Hover Test Facility In the early 1980s, Green and Zanine (refs. 14-16) extended and implemented the methods of reference 12 NPR nozzle pressure ratio in a computer program, REINGST, to attempt a rapid, PSCL Propulsion Simulator Calibration preliminary design estimation of inlet temperature rise Laboratory due to near- and far-field HGI for a jet VTOL aircraft. The method was compared by its authors with the limited SAE Society of Automotive Engineers experimental data which were available at the time and V/STOL vertical/short takeoff and landing found to achieve reasonable success for several aircraft. VTOL vertical takeoff and landing Currently, this is the only nonproprietary code that is available for estimating HGI. The REINGST code was reevaluated in 1990 (ref. 17) to establish its effectiveness Description of the Test Setup for several V/STOL aircraft configurations. Unfortu- nately, the method greatly underpredicted the ITR due to The description of the Jet Calibration and Hover Test near-field recirculation because of inaccurate empirical Facility (JCAHT) test setup includes relatively complete correlations for the temperature decay in the various discussions of the hover test rig (HTR), model nozzle and regions of the flow field. In addition, the method failed to plenum details, model hardware, flow visualization account properly for the geometry of the airplane. This technique, and data acquisition system. A few features of HGI prediction method (refs. 14--16) assumes that the the JCAHT which were not used in this phase of this aircraft has a flat undersurface; as shown in reference 17, investigation are identified in the following discussion. However, information on the entire JCAHT is included to Details of Nozzle and Plenum provide an understanding of the complete experimental The two ASME nozzles were bolted to the rectangular facility.
Load more

Recommended publications
  • A Brief Review on Electromagnetic Aircraft Launch System
    International Journal of Mechanical And Production Engineering, ISSN: 2320-2092, Volume- 5, Issue-6, Jun.-2017 http://iraj.in A BRIEF REVIEW ON ELECTROMAGNETIC AIRCRAFT LAUNCH SYSTEM 1AZEEM SINGH KAHLON, 2TAAVISHE GUPTA, 3POOJA DAHIYA, 4SUDHIR KUMAR CHATURVEDI Department of Aerospace Engineering, University of Petroleum and Energy Studies, Dehradun, India E-mail: [email protected] Abstract - This paper describes the basic design, advantages and disadvantages of an Electromagnetic Aircraft Launch System (EMALS) for aircraft carriers of the future along with a brief comparison with traditional launch mechanisms. The purpose of the paper is to analyze the feasibility of EMALS for the next generation indigenous aircraft carrier INS Vishal. I. INTRODUCTION maneuvering. Depending on the thrust produced by the engines and weight of aircraft the length of the India has a central and strategic location in the Indian runway varies widely for different aircraft. Normal Ocean. It shares the longest coastline of 7500 runways are designed so as to accommodate the kilometers amongst other nations sharing the Indian launch for such deviation in takeoff lengths, but the Ocean. India's 80% trade is via sea routes passing scenario is different when it comes to aircraft carriers. through the Indian Ocean and 85% of its oil and gas Launch of an aircraft from a mobile platform always are imported through sea routes. Indian Ocean also requires additional systems and methods to assist the serves as the locus of important international Sea launch because the runway has to be scaled down, Lines Of Communication (SLOCs) . Development of which is only about 300 feet as compared to 5,000- India’s political structure, industrial and commercial 6,000 feet required for normal aircraft to takeoff from growth has no meaning until its shores are protected.
    [Show full text]
  • Adventures in Low Disk Loading VTOL Design
    NASA/TP—2018–219981 Adventures in Low Disk Loading VTOL Design Mike Scully Ames Research Center Moffett Field, California Click here: Press F1 key (Windows) or Help key (Mac) for help September 2018 This page is required and contains approved text that cannot be changed. NASA STI Program ... in Profile Since its founding, NASA has been dedicated • CONFERENCE PUBLICATION. to the advancement of aeronautics and space Collected papers from scientific and science. The NASA scientific and technical technical conferences, symposia, seminars, information (STI) program plays a key part in or other meetings sponsored or co- helping NASA maintain this important role. sponsored by NASA. The NASA STI program operates under the • SPECIAL PUBLICATION. Scientific, auspices of the Agency Chief Information technical, or historical information from Officer. It collects, organizes, provides for NASA programs, projects, and missions, archiving, and disseminates NASA’s STI. The often concerned with subjects having NASA STI program provides access to the NTRS substantial public interest. Registered and its public interface, the NASA Technical Reports Server, thus providing one of • TECHNICAL TRANSLATION. the largest collections of aeronautical and space English-language translations of foreign science STI in the world. Results are published in scientific and technical material pertinent to both non-NASA channels and by NASA in the NASA’s mission. NASA STI Report Series, which includes the following report types: Specialized services also include organizing and publishing research results, distributing • TECHNICAL PUBLICATION. Reports of specialized research announcements and feeds, completed research or a major significant providing information desk and personal search phase of research that present the results of support, and enabling data exchange services.
    [Show full text]
  • Lockheed Martin F-35 Lightning II Incorporates Many Significant Technological Enhancements Derived from Predecessor Development Programs
    AIAA AVIATION Forum 10.2514/6.2018-3368 June 25-29, 2018, Atlanta, Georgia 2018 Aviation Technology, Integration, and Operations Conference F-35 Air Vehicle Technology Overview Chris Wiegand,1 Bruce A. Bullick,2 Jeffrey A. Catt,3 Jeffrey W. Hamstra,4 Greg P. Walker,5 and Steve Wurth6 Lockheed Martin Aeronautics Company, Fort Worth, TX, 76109, United States of America The Lockheed Martin F-35 Lightning II incorporates many significant technological enhancements derived from predecessor development programs. The X-35 concept demonstrator program incorporated some that were deemed critical to establish the technical credibility and readiness to enter the System Development and Demonstration (SDD) program. Key among them were the elements of the F-35B short takeoff and vertical landing propulsion system using the revolutionary shaft-driven LiftFan® system. However, due to X- 35 schedule constraints and technical risks, the incorporation of some technologies was deferred to the SDD program. This paper provides insight into several of the key air vehicle and propulsion systems technologies selected for incorporation into the F-35. It describes the transition from several highly successful technology development projects to their incorporation into the production aircraft. I. Introduction HE F-35 Lightning II is a true 5th Generation trivariant, multiservice air system. It provides outstanding fighter T class aerodynamic performance, supersonic speed, all-aspect stealth with weapons, and highly integrated and networked avionics. The F-35 aircraft
    [Show full text]
  • Supersonic STOVL Ejector Aircraft from a Propulsion Point of View
    N84-24581 NASA Technical Memorandum 83641 9 Supersonic STOVL Ejector Aircraft from a Propulsion Point of View R. Luidens, R. Plencner, W. Haller, and A. blassman Lewis Research Center Cleveland, Ohio Prepared for the Twentieth Joint Propulsion Coiiference cosponsored by the AIAA, SAE, and ASME i Cincinnati, Ohio, June 11-13, 1984 I 1 1 SUPERSONIC STOVL EJECTOR AIRCRAFT FROH A PROPULSION POINT OF VIEW R hidens,* R. Plencner,** W. Hailer.** and A Glassman+ National Aeronautics and Space Administration Lewis Research Center Cleveland, Ohio Abstract 1 Higher propulsion system thrust for greater lift-off acceleration. The paper first describes a baseline super- sonic STOVL ejector aircraft, including its 2 Cooler footprint, for safer, more propulsion and typical operating modes, and convenient handllng, and lower observability identiftes Important propulsion parameters Then a number of propulsion system changes are 3. Alternattve basic propulsion cycles evaluated in terms of improving the lift-off performance; namely, aft deflection of the ejec- The approach of this paper is to use the tor jet and heating of the ejector primary air aircraft of reference 5 as a baseline. and then either by burning or using the hot englne core to consider some candidate propulsion system flow The possibility for cooling the footprint growth options The vehicle described in refe- is illustrated for the cases of mixing or lnter- rence 5 was selected on the basis of detailed changlng the fan and core flows, and uslng a alrcraft design and performance analyses The
    [Show full text]
  • Modeling and Analysis of Disc Rotor Wing
    © 2020 JETIR March 2020, Volume 7, Issue 3 www.jetir.org (ISSN-2349-5162) MODELING AND ANALYSIS OF DISC ROTOR WING 1 2 3 G. MANJULA , L. BALASUBRAMANYAM , S. JITHENDRA NAIK 1PG scholor, 2Asso.Professor, 3Asso.Professor Mechanical Engineering Department 1P.V.K.K Engineering College, Anantapur, AP, INDIA. Abstract-Disc rotor configuration may be a conceptual design. the aim of the Project is to guage the merits of the DiscRotor concept that combine the features of a retractable rotor system for vertical take-off and landing (VTOL) with an integral, circular wing for high-speed flight. The primary objective of this project is to style such a configuration using the planning software Unigraphics and afterward analyzing the designed structure for its structural strength in analysis software ANSYS. This project deals with the all the required aerodynamic requirements of the rotor configuration. In today’s world most the vtol/stol largely depends upon the thrust vectoring that needs huge amounts of fuel and separate devices like nozzles etc., whose production is extremely much tedious and dear. this is often an effort to use a rotor as within the case of helicopters for vtol/stol thus reducing the foremost of the value though weight would be considered as a hindrance to the project. Keywords: Disc rotor wing, vertical take-off and landing (VTOL), UNIGRAPHICS, ANSYS software, Force, Coefficients, Wall and Wing. I. INTRODUCTION A circular wing, or disc, is that the primary lifting surface of the Disc Rotor aircraft during high-speed flight (approx. 400knots). During the high-speed flight, the disc are going to be fixed (i.e.
    [Show full text]
  • FINAL Kennedy Space Center Florida Scrub-Jay Compensation Plan
    FINAL Kennedy Space Center Florida Scrub-Jay Compensation Plan February 13, 2014 Prepared for: Environmental Management Branch TA-A4C National Aeronautics and Space Administration John F. Kennedy Space Center, Florida 32899 Prepared by: Medical and Environmental Support Contract (MESC) CLIN10 Environmental Projects IHA Environmental Services Branch IHA-022 Kennedy Space Center, Florida 32899 *THIS PAGE INTENTIONALLY LEFT BLANK* ii Kennedy Space Center Florida Scrub-Jay Compensation Plan February 13, 2014 Prepared for: Environmental Management Branch TA-A4C National Aeronautics and Space Administration John F. Kennedy Space Center, Florida 32899 Prepared by: Medical and Environmental Support Contract (MESC) CLIN10 Environmental Projects IHA Environmental Services Branch IHA-022 Kennedy Space Center, Florida 32899 iii ACRONYMS Ac Acre BO Biological Opinion ADP Area Development Plan CCAFS Cape Canaveral Air Force Station CCF Converter Compressor Facility CCP Comprehensive Conservation Plan EO Executive Order CofF Construction of Facilities EA Environmental Assessment EES Emergency Egress Systems ESA Endangered Species Act FAC Florida Administrative Code FDEP Florida Department of Environmental Protection ft feet ft2 square feet FWC Florida Fish and Wildlife Conservation Commission in inches IRL Indian River Lagoon GHe Gaseous Helium ha hectares HIF Horizontal Integration Facility IHA InoMedic Health Applications, Inc. kg kilogram km kilometer KSC Kennedy Space Center lbs pounds LC Launch Complex LH2 Liquid Hydrogen LOX Liquid Oxygen mmeter
    [Show full text]
  • Aviation Acronyms
    Aviation Acronyms 5010 AIRPORT MASTER RECORD (FAA FORM 5010-1) 7460-1 NOTICE OF PROPOSED CONSTRUCTION OR ALTERATION 7480-1 NOTICE OF LANDING AREA PROPOSAL 99'S NINETY-NINES (WOMEN PILOTS' ASSOCIATION) A/C AIRCRAFT A/DACG ARRIVAL/DEPARTURE AIRFIELD CONTROL GROUP A/FD AIRPORT/FACILITY DIRECTORY A/G AIR - TO - GROUND A/G AIR/GROUND AAA AUTOMATED AIRLIFT ANALYSIS AAAE AMERICAN ASSOCIATION OF AIRPORT EXECUTIVES AAC MIKE MONRONEY AERONAUTICAL CENTER AAI ARRIVAL AIRCRAFT INTERVAL AAIA AIRPORT AND AIRWAY IMPROVEMENT ACT AALPS AUTOMATED AIR LOAD PLANNING SYSTEM AANI AIR AMBULANCE NETWORK AAPA ASSOCIATION OF ASIA-PACIFIC AIRLINES AAR AIRPORT ACCEPTANCE RATE AAS ADVANCED AUTOMATION SYSTEM AASHTO AMERICAN ASSOCIATION OF STATE HIGHWAY & TRANSPORTATION OFFICIALS AC AIRCRAFT COMMANDER AC AIRFRAME CHANGE AC AIRCRAFT AC AIR CONTROLLER AC ADVISORY CIRCULAR AC ASPHALT CONCRETE ACAA AIR CARRIER ACCESS ACT ACAA AIR CARRIER ASSOCIATION OF AMERICA ACAIS AIR CARRIER ACTIVITY INFORMATION SYSTEM ACC AREA CONTROL CENTER ACC AIRPORT CONSULTANTS COUNCIL ACC AIRCRAFT COMMANDER ACC AIR CENTER COMMANDER ACCC AREA CONTROL COMPUTER COMPLEX ACDA APPROACH CONTROL DESCENT AREA ACDO AIR CARRIER DISTRICT OFFICE ACE AVIATION CAREER EDUCATION ACE CENTRAL REGION OF FAA ACF AREA CONTROL FACILITY ACFT AIRCRAFT ACI-NA AIRPORTS COUNCIL INTERNATIONAL - NORTH AMERICA ACID AIRCRAFT IDENTIFICATION ACIP AIRPORT CAPITAL IMPROVEMENT PLANNING ACLS AUTOMATIC CARRIER LANDING SYSTEM ACLT ACTUAL CALCULATED LANDING TIME Page 2 ACMI AIRCRAFT, CREW, MAINTENANCE AND INSURANCE (cargo) ACOE U.S. ARMY
    [Show full text]
  • Aircraft Design Class 2008
    AircraftAircraft DesignDesign ClassClass Sam B. Wilson III Chief Visionary Officer AVID LLC www.avidaerospace.com 9 September 2008 TTO Tactical Technology Office 9 Sept.’08 / pg # 2 DesignDesign MethodsMethods What Size? What Shape? 9 Sept.’08 / pg # 3 Design “As Drawn” Computer evaluation of Conceptual Designs “As Drawn” Assumes fixed external mold- lines JSFJSF X-35BX-35B Weight as independent variable - “loop 9 Sept.’08 / pg # 4 closure” IntegrationIntegration Challenge:Challenge: To design a supersonic fighter/attack aircraft that offers the operational flexibility of Short Takeoff and Vertical Landing (STOVL) Need to make the same design compromises as a conventional fighter, plus one: use the available thrust in a manner that allows a controlled vertical landing This single added constraint requires a more systematic approach to the design of an aircraft. 9 Sept.’08 / pg # 5 V/STOLV/STOL AircraftAircraft DesignDesign ProcessProcess Step 1 Define wing & horizontal stabilizer geometry Located engine “vertical thrust” center with respect to aerodynamic center 9 Sept.’08 / pg # 6 Ref NASA CR-177437 V/STOLV/STOL AircraftAircraft DesignDesign ProcessProcess Step 2 Add minimum length inlet/diffuser Add cockpit and forebody 9 Sept.’08 / pg # 7 Ref NASA CR-177437 V/STOLV/STOL AircraftAircraft DesignDesign ProcessProcess Step 3 Add vertical tails Assign location dependent masses landinglanding geargear flightflight controlscontrols radarradar 9 Sept.’08 / pg # 8 Ref NASA CR-177437 V/STOLV/STOL AircraftAircraft DesignDesign ProcessProcess
    [Show full text]
  • Development of a Methodology for Parametric Analysis of STOL Airpark Geo-Density
    Development of a Methodology for Parametric Analysis of STOL Airpark Geo-Density Joseph N. Robinson∗, Max-Daniel Sokollek†, Cedric Y. Justin‡, and Dimitri N. Mavris§ Georgia Institute of Technology, Atlanta, Georgia, 30332-0150, United States Vehicles designed for urban air mobility (UAM) or on-demand mobility (ODM) applications typically adopt an architecture enabling vertical takeoff and landing (VTOL) capabilities. UAM or ODM systems featuring these capabilities typically have a smaller ground footprint but are subject to a number of performance compromises that make sizing and optimizing the vehicles more challenging. These design challenges can be further compounded when additional environmental considerations are taken into account and in particular if electric propulsion is considered. Alternative architectures such as short takeoff and landing (STOL) and super-short takeoff and landing (SSTOL) vehicles are thus investigated because they present possible advantages in terms of energy efficiency, overall vehicle performance, and noise footprint. However, the larger ground footprint of the infrastructure necessary to operate these systems means that these systems may be more difficult to integrate into a urban and suburban environment. One objective of this research is to estimate the geo-density of airparks suitable for STOL and SSTOL operations based on vehicle performance and ground footprint parameters. In turn, this helps establish requirements for the field performances of STOL and SSTOL vehicles to be considered for ODM and UAM applications. This research proposes and interactive and parametric design and trade-off analysis environment to help decision makers assess the suitability of candidate cities for STOL and SSTOL operations. Preliminary results for the Miami metropolitan area show that an average airpark geo-density of 1.66 airparks per square mile can be achieved with a 300 foot long runway.
    [Show full text]
  • Small-Scale Experiments in STOVL Ground Effects
    NASA Technical Memorandum 102813 Small-Scale Experiments in STOVL Ground Effects Victor R. Corsiglia and Douglas A. Wardwell, Ames Research Center, Moffett Field, California Richard E. Kuhn, STO-VL Technology, San Diego, California April 1991 National Aeronautics and Space Administration Ames Research Center Moffett Field, California 94035-1000 SMALL-SCALE EXPERIMENTS IN STOVL GROUND EFFECTS Victor R. Corsiglia and Douglas A. Wardwell NASA Ames Research Center Moffett Field, California, 94035 USA Richard E. Kuhn STO-VL Technology San Diego, California, 92128 USA Abstract Pi local static pressure A series of tests has been completed inwhich Pjet total pressure at jet exit suckdown and fountain forces and pressures were measured on circular plates and twin-tandem-jet AM jet induced pitching moment generic STOVL (short takeoff and vertical landing) configurations. The tests were conducted using a Ap local pressure difference; _P = small-scale hover rig, for jet pressure ratios up to 6 Pi- Pamb and jet temperatures up to 700 °F. The measured suckdown force on a circular plate with a central jet S model planform area was greater than that found with a commonly used empidcal prediction method. The present data T thrust, T = 7.0 A( Pamb)[(NPR 0.286) -1], showed better agreement with other sets of data. NPR < 1.893 The tests of the generic STOVL configurations were conducted to provide tome and pressure data with T = A(Pamb)[(1.2679)NPR -1 ], a parametric variation of parameters so that an NPR > 1.893 empirical prediction method could be developed. The effects of jet pressure ratio and temperature T jet temperature were found to be small.
    [Show full text]
  • WYVER Heavy Lift VTOL Aircraft
    WYVER Heavy Lift VTOL Aircraft Rensselaer Polytechnic Institute 1st June, 2005 1 ACKNOWLEDGEMENTS We would like to thank Professor Nikhil Koratkar for his help, guidance, and recommendations, both with the technical and aesthetic aspects of this proposal. 22ND ANNUAL AHS INTERNATIONAL STUDENT DESIGN COMPETITION UNDERGRADUATE CATEGORY Robin Chin Raisul Haque Rafael Irizarry Heather Maffei Trevor Tersmette 2 TABLE OF CONTENTS Executive Summary.................................................................................................................................. 4 1. Introduction........................................................................................................................................... 9 2. Design Philosophy.............................................................................................................................. 10 2.1 Mission Requirements .................................................................................................................. 11 2.2 Aircraft Configuration Trade Study.............................................................................................. 11 2.2.1 Tandem Design Evaluation.................................................................................................... 12 2.2.2 Tilt-Rotor Design Evaluation ................................................................................................ 15 2.2.3 Tri-Rotor Design Evaluation ................................................................................................
    [Show full text]
  • NASA SUPERSONIC STOVL PROPULSION TECHNOLOGY PROGRAM Peter G
    NASA Technical Memorandum 100227 NASA Supersonic STOVL Propulsion ~ Technology Program (HASA-TR-100227) NASA SUPERSONIC STOVL PBOPIJLSIOl TECBHOLOGY PROGRAW (RASA) 20 P N88- 14093 CSCL 2iS Unclas G3/07 0116607 Peter €3. Batterton and Bernard J. Blaha Lewis &search Center i%velunti, Ohio Prepared for the htemational Poweted Lift Codenace sponsored by the Society of Automotm l3Dgheem Santa Clara, California, December 7-10,19$7 NASA SUPERSONIC STOVL PROPULSION TECHNOLOGY PROGRAM Peter G. Batterton and Bernard J. Blaha National Aeronautics and Space Administration Lewis Research Center I. Cleveland, Ohio 44135 ABSTRACT technology is the key to allowing it to happen (1,2)*. Supersonic capable STOVL fighter/at ack air- It has always been a goal of NASA Aeronau- craft can provide capabilities for close support tics Research to address and resolve high risk, and air superiority which will be highly desira- long lead technologies. An attempt to design a ble in the future. Previous papers in this current advanced, supersonic cruise capable STOVL session described the historical aspects, trade- fighter aircraft would lead to the conclusion offs, and requirements for powered lift propul- that the required propulsion technologies are not sion systems, and it is shown that propulsion available. Further, demonstration of these tech- technology is more key to the success of this nologies will be required before the DoD and type of aircraft than for any previous fighter/ industry will attempt even a prototype. There- attack aircraft. This paper discusses the NASA fore, the overall goal of the program and pro- Lewis Research Center program activities which jects described in this paper is to have the pro- address required propulsion technology develop- pulsion technology in place to permit the low ment.
    [Show full text]