Weidlinger Associates

About Weidlinger Associates

Weidlinger Assoc. is a company that received a Department of Defense SBIR/STTR grant for a project entitled: Metamaterials for Acoustic Cloaking. The abstract given for this project is as follows: New metamaterials promise to improve radically the ability of structures to evade sonar detection. The physics of these 'acoustic mapped metamaterials' (AMM) is novel: by careful design of their elastic properties, a coating made of AMM materials guides waves around and away from a 'cloaked' internal region, rendering the object inside undetectable by active sonar. Like all technologies, AMM will require considerable effort before it becomes a practical reality. AMM theory has only recently been cast in a usable form, by Norris ('Acoustic Cloaking Theory,' Proceedings of the Royal Society A, online May 2008, doi: 10.1098/rspa.2008.0076); previous theories based on extensions of electromagnetics are not physically realizable. Consequently, we propose to conduct extensive numerical experimentation and development to minimize risk. The AMM theory will be deployed to a well-verified finite element code, PZFlex . This development will enable us to test the AMM theory on submarine-like shapes. In addition, we propose to conduct finite element studies of AMM microstructures, in order to ensure that the proposed materials exhibit the desired, complicated and unique elastic properties. These unit-cell analyses will guide the design of manufacturable composites. Finally, our proposed work includes detailed consultation with established manufacturers of naval composite materials, to ensure the AMM microstructures can be manufactured at full scale and low cost. Weidlinger Assoc. is a company that received a Department of Defense SBIR/STTR grant for a project entitled: User Toolkit for Reducing Cost and Time in the Design of SONAR Systems Using Relaxor Piezoelectric Single Crystals. The abstract given for this project is as follows: WAI will develop a suite of User Toolkits for SONAR Transducer Design, to enable rapid and accurate evaluation of new design concepts, allowing quick selection of appropriate candidate designs for further evaluation. This will reduce overall design costs and time from concept to market. The Toolkits will be heavily influenced by devices incorporating single crystal piezoelectric materials. The technology for the simulation used in the Toolkits will be based on PZFlex, a finite element simulation package heavily used in the ultrasound and SONAR communities, leveraging decades of development effort in that field. The Toolkits will allow for all relevant input parameters (materials, dimensions etc) to be varied, while calculating and displaying all key output metrics such as electrical impedance profile, TVR, and directivity. WAI, in partnership with Materils systems Inc, will initially develop a Toolkit focused on the Langevin (sandwich) class of transducer, for consideration for use in the AN/AQS-20 Minehunter. Following development and validation of the Toolkit, MSI will design a candidate Forward Looking SONAR with the Toolkit, incorporating single crystal piezoelectric material, to replace the existing Tonpilz design. Key performance metrics will be compared with existing data to highlight improvements available from use of new design and materials. Weidlinger Assoc. is a company that received a Department of Defense SBIR/STTR grant for a project entitled: Engineering Models for Damage to Structural Components Subjected to Internal Blast Loading. The abstract given for this project is as follows: Predicting the response of building components to internal detonations is more complex than the corresponding task for external loads because of the more complex loading waveforms which include multiple reflections in the shock phase followed by a long duration pseudostatic loading that depends upon room venting. Add the possibility of additional impulsive loading from primary debris. We propose to generate a fast running model capable of predicting damage from internal detonations incurred by a wide variety structural components, materials and construction methods, e.g., steel stud walls, reinforced concrete, concrete masonry units, etc. Step one involves categorizing and simplifying the variety of possible loading wave forms and parametrizing them for use as loading functions in the detonation room as well as adjacent rooms. We propose to use the MAZ computational fluid dynamics code and available experimental data to categorize the appropriate waveforms and then reduce them to simplified loading functions that produce the equivalent structural responses. We will use the FLEX computational structural dynamics code plus existing test data to generate a damage data base that will be incorporated into a fast running damage response model. The model will be validated against first principles computations and existing and new test data. Weidlinger Assoc. is a company that received a Department of Defense SBIR/STTR grant for a project entitled: Piezoelectric Single Crystal Stacks for Improved Fuel Injector Performance. The abstract given for this project is as follows: Engine performance and fuel consumption in the Navy's surface ships, submersibles, and aircraft are a significant concern from both an operations and logistics viewpoint. Higher fuel efficiency leads to longer times between resupply or lower operating costs, while increased performance is always desired during combat operations. We propose the use of single crystal piezoelectric materials to enhance the performance of a critical aspect of combustion engine technology, the electronic fuel injector, to improve both performance and efficiency. By replacing the existing piezoceramic driving technology with piezoelectric single crystals we will improve the three critical requirements for fuel injector actuators: stroke, force output, and bandwidth. This can be achieved in a component of identical size, or smaller than, existing driving stacks, and may allow for the omission of displacement amplification systems resulting in smaller, less expensive fuel injectors. The higher performance of the fuel injectors will allow for more precise control of engine performance, allowing the Navy to choose between higher power, greater fuel efficiency, or lower emissions from their engines. Weidlinger Assoc. is a company that received a Department of Defense SBIR/STTR grant for a project entitled: Novel Methods to Measure Penetrator Dynamics in Multi-Layer Geometries. The abstract given for this project is as follows: This proposal describes an approach to meeting DTRA's goals of improving sensor technology for penetrating weapons. Weidlinger Associates Inc. (WAI) has significant experience in the design and use of ultrasound technologies for a broad range of end-use applications. WAI is also familiar with the terradynamic issues related to penetrators and the targeting aspects through its work in Hard Target Defeat projects over the last ten years. WAI proposes to combine its expertise in impact and penetration dynamics and in ultrasonic/acoustic sensors design to develop an effective acoustic sensor design for penetrating weapons during this Phase I effort. The sensor will provide measurement data that will contribute to (a) distinquishing the acoustic signature of different materials during penetration, (b) quantifying the operating environment (frequencies, noise levels, etc.) of sensors onboard a penetrator and (c) guide improvements in the acoustic sensor's design in later development phases. Weidlinger Associates is a company that received a Department of Defense SBIR/STTR grant for a project entitled: Weapons Effects FRMs for Reinforced Concrete Walls & Floor/Ceiling Slabs. The abstract given for this project is as follows: The Air Force Research Laboratory developed the MEVA software for weaponeering applications. MEVA allows a weaponeer to quickly study alternative targeting scenarios to maximize the effectiveness of a mission while minimizing the risk to the warfighter and the potential for collateral damage. MEVA needs to be upgraded to support targeting needs for structures with RC slabs and walls that fall outside the current specifications of its blast response modules. The main areas of enhancement required are: Support for higher strength concrete materials Support for the full range of hardened and civil construction that is (or will be) supported by STMG Support for the expanded range of loading produced by new weapon systems available to the weaponeer such as the MOP Support for more complex representations of blast pressure waveforms resulting from internal propagation through complex structural geometries Addition of new response measures such as breach and fragment/debris data that increase MEVAs effectiveness to support mission planning. WAI proposes to demonstrate proof of concept methods to address each of these areas in Phase I and develop the new software tools and integrate them within the MEVA software in a follow-on Phase II effort.BENEFIT:WAI has successfully commercialized products produced by previous SBIR efforts including the PZFlex software for piezoelectric modeling applications which will generate $1,000,000 revenue in the year 2008. The primary market for the blast modules developed under this SBIR would primarily be other DoD organizations in the U.S. For example, DTRA develops and maintains the IMEA software for offensive targeting needs. The new modules have direct application to IMEA and other similar software environments. Additionally, HFPB modeling of HSC and UHSC structures is an increasingly important area for a number of DoD agencies. WAI anticipates that the increased experience and validation that will result from this effort will directly result in increasing WAIs consulting business in this area. WAI also anticipates an increase in sales of the NLFlex software to government groups interested in HFPB modeling of HSC and UHSC materials. Weidlinger Associates is a company that received a Department of Defense SBIR/STTR grant for a project entitled: Non-Spherical Blast in a Cluttered Environment. The abstract given for this project is as follows: Physics-based computational solutions facilitate the understanding of the behavior of structures subjected to high-explosives. However, design and parameter studies remain costly, because computational fluid mechanics models of blast waves may require supercomputers. On the other hand, extremely efficient approximate models of blast loading fail to resolve the effects of interest: close-proximity blast, non-spherical charges, complex geometry, motion of the charge, reflections and shadowing in a cluttered environment. The proposed approach combines the efficiency of approximate blast loading models with resolution of the required effects. Since commercially available explicit Lagrangian finite element software technology is almost always used to analyze structures exposed to blast loading, our module will be implemented using such a code. Weidlinger has already demonstrated software for close-in charges which synthesizes pressure distributions using stored, pre-computed CFD solutions. CFD is not performed at runtime. The proposed module will blend established empirical formulae and the synthesized, CFD-based pressure functions. Charge motion will be accounted for by linear Doppler theory. Reflections will be handled using ray-tracing for general surfaces defined in terms of finite element geometry, computing lines of sight, interaction distances and occlusion for facets in the surface. The module will be validated against experimental data.BENEFITS:The modular blast software technology proposed here will deliver numerous direct and indirect commercial benefits. The immediate commercial application will be to the simulation of blast effects on airframe structures of interest to the Air Force, and to ground targets. The advantages of a high-resolution pure-Lagrangian approach in these applications are considerable. By avoiding computational fluid dynamics or other computer-intensive methods, the analyst can concentrate on the aircraft or ground structure of interest and explore many more cases for the same expenditure of resources. The modular design of the proposed blast loading module(s) allows WAI to access the large existing markets consisting of users of LS-DYNA, Abaqus, and DYTRAN, as well as Weidlingers NLFlex and EPSA codes. Weidlinger Associates is a company that received a Department of Defense SBIR/STTR grant for a project entitled: Novel Accelerator Architectures for Critical DoD Application. The abstract given for this project is as follows: Large scale shock physics simulations comprise a critical element of the analysis of the survivability of ships and submarines in response to underwater explosions, subsurface bunker vulnerability to ground shock, and response of buildings and vehicles to airborne explosions. Explicit time-domain finite element methods have proven to be a necessity for the successful simulation of such problems, with the proviso that the software itself be subject to rigorous verification and validation. Capturing multiscale shock physics phenomena in all its detail requires ever increasing resolutions in space and time and therefore, software and hardware methods for these critical DoD applications must be continually pushed to the limits of available technology. Much of the critical validation data is classified, limiting the number of software tools which can reasonably be considered valid for this class of problem. WAI proposes the acceleration of its validated, explicit, time-domain Lagrangian shock physics code FUSE using GPUs. Using a validated, in- house computer code will result in reduced development time and costs. This project will endeavor to deliver shock physics computer codes faster by an order of magnitude, cutting down the time involved in solving practical shock physics from weeks to days. Weidlinger Associates is a company that received a Department of Defense SBIR/STTR grant for a project entitled: High Fidelity Modeling of Building Collapse with Realistic Visualization of Resulting Damage and Debris. The abstract given for this project is as follows: Develop a validated high fidelity physics based computational method to evaluate building performance and collapse under blast loading with the capability to show the resulting damage and debris fly-out in a realistic fashion. Key requirements for the developed method are: 1) sufficient fidelity to capture critical phenomena in building collapse and 2) an intelligent user friendly interface to allow practicing engineers to obtain accurate results faster than the current traditional high fidelity computational methods. DESCRIPTION: The Defense Threat Reduction Agency (DTRA) seeks proposals for development of a high fidelity model for analysis of building collapse under blast loading. Realistic visualization of the damage and debris is an important aspect of the requirements in order to assess damage to Weapons of Mass Destruction (WMD) containers in a targeted building or to assess vulnerability of personnel and mission critical equipment in a protected facility. Structural collapse under blast conditions involves an initially stable structure acted upon by gravity loads, followed by the imposition of blast loads (a relatively short duration event) which induce material and structural damage. The latter in turn, may lead to global structural instabilities which can result to the collapse of the original structure. Computational modeling of collapse entails three dimensional (3D) geometry, non-linear material and geometry, and highly dynamic events such as material breakup and ejection. In the past several decades the Finite Element Method (FEM) has been used successfully to model complex dynamic events including building collapse. FEM formulations have incorporated implicit, explicit or hybrid integration techniques to accurately model various phenomena in building collapse. To capture the results for visual presentations the FEM models typically run over the entire collapse event which may take several weeks to months of computer run time. Sophisticated mathematical formulations have been developed for more efficient computations and for fracture and breakup of materials. However, their proper implementation requires a highly educated and experienced scientist or engineer. Often times the results generated by the FEM model differ depending on the experience of the user with the FEM model of interest. The extensive computation time and high level of expertise required to use existing FEM models for building collapse are barriers to wide use of the technology. To overcome these barriers an innovative computational method is sought that a practicing engineer can install on a single or dual processor personal computer and use it to model a collapse event within a couple of days of computer run-time.