Fixed wing CCW aerodynamics with and without supplementary thrust deflection

The concept of circulation control was successfully demonstrated in flight using an A-6 aircraft. Circulation control can provide an aircraft with STOL performance of heavy lift capability. For ship based Naval aircraft the lower takeoff and landing velocities result in reduced deck gear and wind over the deck requirements. Circulation control airfoils can be mechanically less complex and lightweight compared to multi-element high lift airfoils

Torque and temperature dependence of the hysteretic voltage-induced torsional strain in tantalum trisulfide

We have measured the dependence of the hysteretic voltage-induced torsional strain (VITS) in crystals of orthorhombic tantalum trisulfide on temperature and applied torque. In particular, applying square-wave voltages above the charge-density-wave (CDW) threshold voltage, so as to abruptly switch the strain across its hysteresis loop, we have found that the time constant for the VITS to switch (at different temperatures and voltages) varied as the CDW current. Application of torque to the crystal could also change the VITS time constant, magnitude, and sign, suggesting that the VITS is a consequence of residual torsional strain in the sample which twist the CDW. Application of voltage changes the pitch of these CDW twists, which then act back on the lattice. However, it remains difficult to understand the sluggishness of the response.Comment: 20 pages, including 7 figures, to be published in PR

Large-scale static investigation of circulation-control-wing concepts applied to upper surface-blowing aircraft

The use of a circulation control to deflect turbofan engine thrust beyond 90 deg. has been proven in full-scale static ground tests of the circulation-control-wing/upper-surface-blowing (CCW/USB) concept. This powered high-lift system employs a circular, blown trailing edge to replace the USB mechanical flaps to entrain engine-exhaust flow, and to obtain both a vertical-thrust component and an augmented circulation lift for short takeoff and landing (STOL) applications. Previous tests (Phase 1), done in 1982, of a basic configuration installed on the Quiet Short Haul Research Aircraft confirmed these CCW/USB systems capabilities. A second phase (Phase 2) of full-scale, static, thrust-deflection investigations has reconfirmed the ability to deflect engine thrust from 40 to 102 deg., depending on thrust level. Five new configurations were evaluated and performance improvements noted for those configurations with larger blown span, fences or favorable engine interactions, smaller slot height, and larger radii with less than 180 deg. of CCW surface arc. In general, a 90 deg. circular arc with a smaller slot height provided the best performance, demonstrating that adequate thrust turning can be produced by a trailing-edge shape which may have minimal cruise-performance penalty. Thrust deflections were achieved at considerably lower blowing momentum than was required for the baseline case of Phase 1. Improved performance and versatility were thus confirmed for the CCW/USB system applied to STOL aircraft, where the potential for developing a non-moving-parts pneumatic thrust deflector to rapidly vary horizontal force from thrust to drag, while maintaining constant vertical force, appears quite promising. The conversion from high-lift to lower-drag cruise mode by merely terminating the blowing provides an effective STOL aircraft system

Back to the Future: Towards a Cultural Archive of la Movida

Toward a Cultural Archive of la Movida revisits the cultural and social milieu in which la Movida, an explosion of artistic production in the late 1970s and early 1980s, was articulated discursively, aesthetically, socially, and politically. We connect this experience with a broader national and international context that takes it beyond the city of Madrid and outside the borders of Spain. This collection of essays links the political and social undertakings of this cultural period with youth movements in Spain and other international counter-cultural or underground movements. Moving away from biographical experiences or the identification of further participants and works that belong to la Movida, the articles collected in this volume situate this movement within the political and social development of post-Franco Spain. Finally, it also offers a reading of recent politically motivated recoveries of this cultural phenomenon through exhibitions, state sponsored documentaries, musicals, or tourist itineraries. The perception of Spain as representative of a successful dual transition from dictatorship to democracy and free market capitalism created a “Spanish model” that has been emulated in countries like Portugal, Argentina, Chile and Hungary, all formerly ruled by totalitarian regimes. While social scientists study the promises, contradictions and failures of the Spanish Transición—especially on issues of memory, repression, and (the lack of) reconciliation —our approach from the humanities offers another vantage point to a wider discussion of an unfinished chapter in recent Spanish history by focusing on la Movida as the “cultural archive” whose cultural transitions parallel the political and economic ones. The transgressive, urban nature of this movement demonstrated an overt desire, especially among Spanish youth, to reach onto a global arena emulating the punk and new wave aesthetic of such cities as London, New York, Paris, and Berlin. Art, design, film, music, fashion during this period helped to forge a sense of a modern urban identity in Spain that also reflected the tensions between modernity and tradition, global forces and local values, international mass media technology and regional customs

Static investigation of the circulation control wing/upper surface blowing concept applied to the quiet short haul research aircraft

Full scale static investigations were conducted on the Quiet Short Haul Research Aircraft (QSRA) to determine the thrust deflecting capabilities of the circulation control wing/upper surface blowing (CCW/USB) concept. This scheme, which combines favorable characteristics of both the A-6/CCW and QSRA, employs the flow entrainment properties of CCW to pneumatically deflect engine thrust in lieu of the mechanical USB flap system. Results show that the no moving parts blown system produced static thrust deflections in the range of 40 deg to 97 deg (depending on thrust level) with a CCW pressure of 208,900 Pa (30.3 psig). In addition, the ability to vary horizontal forces from thrust to drag while maintaining a constant vertical (or lift) value was demonstrated by varying the blowing pressure. The versatility of the CCW/USB system, if applied to a STOL aircraft, was confirmed, where rapid conversion from a high drag approach mode to a thrust recovering waveoff or takeoff configuration could be achieved by nearly instantaneous blowing pressure variation

Back to the Future: Towards a Cultural Archive of la Movida

Toward a Cultural Archive of la Movida revisits the cultural and social milieu in which la Movida, an explosion of artistic production in the late 1970s and early 1980s, was articulated discursively, aesthetically, socially, and politically. We connect this experience with a broader national and international context that takes it beyond the city of Madrid and outside the borders of Spain. This collection of essays links the political and social undertakings of this cultural period with youth movements in Spain and other international counter-cultural or underground movements. Moving away from biographical experiences or the identification of further participants and works that belong to la Movida, the articles collected in this volume situate this movement within the political and social development of post-Franco Spain. Finally, it also offers a reading of recent politically motivated recoveries of this cultural phenomenon through exhibitions, state sponsored documentaries, musicals, or tourist itineraries. The perception of Spain as representative of a successful dual transition from dictatorship to democracy and free market capitalism created a “Spanish model” that has been emulated in countries like Portugal, Argentina, Chile and Hungary, all formerly ruled by totalitarian regimes. While social scientists study the promises, contradictions and failures of the Spanish Transición—especially on issues of memory, repression, and (the lack of) reconciliation —our approach from the humanities offers another vantage point to a wider discussion of an unfinished chapter in recent Spanish history by focusing on la Movida as the “cultural archive” whose cultural transitions parallel the political and economic ones. The transgressive, urban nature of this movement demonstrated an overt desire, especially among Spanish youth, to reach onto a global arena emulating the punk and new wave aesthetic of such cities as London, New York, Paris, and Berlin. Art, design, film, music, fashion during this period helped to forge a sense of a modern urban identity in Spain that also reflected the tensions between modernity and tradition, global forces and local values, international mass media technology and regional customs