Boom Configuration Research Articles

Basic principles for creating light, efficient and safe structures for the next generation supersonic transport

An analysis of the critical factors affecting the next generation supersonic transport flight safety, due to the features of the low sonic boom configuration, was carried out. A new concept of a hybrid airframe design of a supersonic passenger jet based on pro-bionic sections and sections of conventional structural layout was proposed. Pro-bionic sections were developed on the basis of composite lattice structures. Previously, this type of structural layouts has been successfully adapted in commercial space vehicles in Russia and the EU. Pro-bionic supersonic passenger jet airframe sections include a rigid composite frame of unidirectional ribs, elastic panels based on 3D reinforced woven skins. These sections are equipped with a built-in structural health monitoring system based on fiber optic sensors. New principles for ensuring pro-bionic structural strength and enhanced flight safety based on the positive synergetic interaction of the primary structural elements are proposed and validated. The weight efficiency of pro-bionic structures is estimated.

Spray nozzles and curtain of chains in fungicide application to control Asian soybean rust

The proper choice of spray nozzles and spray boom configuration is of paramount importance for fungicidal effectiveness, promoting better foliar coverage, especially in the lower canopy of the crop. In this sense, the present study evaluates the influence of fungicides applied with different spray nozzles, with and without curtain of chains, on Asian rust control and on the yield of soybean cultivar BMX Ativa RR. The experimental design was a randomized block, with four spray nozzles (Albuz ® ATR 1.0; Albuz ® ATR 0.5; Magnojet ® ADT 11002; and Magnojet ® CH100) and two spray boom configurations (with curtain of chains; and without curtain of chains). The experiment had four replicates and a control without fungicide application. The variables under study were the severity and control of Asian soybean rust, thousand grain weight, and soybean yield. The results indicate that using the curtain of chains in fungicide applications is a technically viable alternative to increase soybean yield. When used along with empty conical jet and triple flat jet nozzles, this technology is highly efficient in controlling Asian soybean rust.

An assessment of the feasibility of using skirt containment boom together with paravanes for offshore response

Abstract The use of conventional offshore containment boom is a recognised way of containing and recovering oil spilt at sea. However, there are various operational and logistical challenges with their use. One of the largest being that their containment becomes ineffective when towed through the water at speeds of greater than 0.75 knots. Containment and collection of oil using high speed systems allows for greater tow speeds (2–3 knots) without failure and can be operated with a paravane as a single ship system. Oil Spill Response Limited (OSRL) have had numerous requests from its members to supply offshore containment and recovery systems suitable for a single vessel deployment. The reason for this was to help with the challenges of low availability of vessels suitable for offshore operations and to reduce high costs. OSRL have used manufacturers guidance to advise its members on the best options however wished to have its own data to further support this guidance and provide user-validated recommendations to its members. OSRL have investigated the viability of using a paravane with a conventional offshore boom using field tests. These tests focused on vessel tow speed, current speed, boom containment effectiveness and encounter area. A number of deployments were carried out using conventional inflation boom and a medium sized paravane in Southampton Water, UK in 2018 (Figure 1). Observations were gathered to identify the point of boom failure when towed at different speeds and whether a suitable encounter area could be achieved. This poster will provide the detail on the feasibility of towing a conventional offshore boom with a single vessel and paravane, see boom configuration in Figure 2. It will outline specifications and parameters which make for a successful / unsuccessful deployment of conventional boom with paravane and provide recommendations for Tier 1 single vessel deployment equipment.

Aerodynamic Optimization Design on Supersonic Transports Considering Sonic Boom Intensity

It is key points to improve the aerodynamic efficiency and decrease the sonic-boom intensity for the supersonic aircraft design. Sonic-boom prediction method with high precision combining the near-field sonic-boom prediction based on Reynolds-Averaged Navier-Stokes equations and the far-field sonic-boom prediction based on waveform parameter method is firstly established. Then the gradient of sonic boom with respect to the design variables is calculated by the finite difference method and is combined with the gradient of the aerodynamic object by the discrete adjoint technique, acting as the gradient of the weighed object function. Assembling two gradients, the optimization system couples Free Form Deform method、the dynamic mesh technique based on Inverse Distance Weighting interpolation method、the gradient-based optimization algorithm based on the sequential quadratic programming. Using the aerodynamic optimization system considering the sonic boom intensity, the paper conducts a nose angle deflection optimization design and an elaborate aerodynamic optimization including huge design variables and constraints on a supersonic business jet, while the optimization objects are the weighed object and the supersonic cruise drag coefficient. The results show that the nose is deflected downward and the shock wave pattern is changed, leading to a lower far-field maximum overpressure; the drag is decreased by 15.8 counts, and the wing load is moved inboard, also, the pressure drag of the outer wing reduces. Meanwhile, the pressure distribution in the outer wing has a weaker adverse pressure gradient and a more gentle pressure recovery. After optimization, the low-drag and low-sonic boom configuration is obtained, which verified the effectiveness of the optimization system.

Flutter of the unmanned aerial vehicle from composite materials with Wing-Tail Boom Configuration

Flutter of the unmanned aerial vehicle from composite materials with Wing-Tail Boom Configuration

Concrete pumping and its effect on the air void system

Pumping is the most utilized concrete placement technique on construction sites around the globe. Despite being used since the 1960s, a large portion of the knowledge related to the understanding of the concrete pumping process—especially with a focus on the effect of pumping on the concrete air void system—was generated through experience, and thus creating a need for a research-based approach to broaden our understanding of the process and how it affects in-place concrete properties. In this paper, three research campaigns are described. Two controlled large-scale experiments investigating both conventional concrete (CVC) and self-consolidating concrete (SCC) were conducted, in addition to a field research program where concrete pumping in real-world conditions was studied. The air void system of each pumped concrete mixture was characterized before and after pumping, both in plastic and hardened states. Additionally, concrete pressure during pumping was monitored for CVC mixtures. Lastly, Super Air Meter measurements were conducted on fresh concrete. It was shown that the characteristics of the pumping system, such as boom configuration, flow rate, or pumping pressure, do not correlate with the changes in the air void system due to pumping for CVC, however, a relationship between the change in the spacing factor and concrete flow rate was observed for SCC. Our results also indicate that the changes in the air void system induced by pumping are dependent on the particular mixture design and discharge conditions at the point of placement.

Gossamer-1: Mission concept and technology for a controlled deployment of gossamer spacecraft

Gossamer structures for innovative space applications, such as solar sails, require technology that allows their controlled and thereby safe deployment. Before employing such technology for a dedicated science mission, it is desirable, if not necessary, to demonstrate its reliability with a Technology Readiness Level (TRL) of six or higher.The aim of the work presented here is to provide reliable technology that enables the controlled deployment and verification of its functionality with various laboratory tests, thereby qualifying the hardware for a first demonstration in low Earth orbit (LEO). The development was made in the Gossamer-1 project of the German Aerospace Center (DLR).This paper provides an overview of the Gossamer-1 mission and hardware development. The system is designed based on the requirements of a technology demonstration mission. The design rests on a crossed boom configuration with triangular sail segments. Employing engineering models, all aspects of the deployment were tested under ambient environment. Several components were also subjected to environmental qualification testing.An innovative stowing and deployment strategy for a controlled deployment, as well as the designs of the bus system, mechanisms and electronics are described. The tests conducted provide insights into the deployment process and allow a mechanical characterization of that deployment process, in particular the measurement of the deployment forces.Deployment on system level could be successfully demonstrated to be robust and controllable. The deployment technology is on TRL four approaching level five, with a qualification model for environmental testing currently being built.

The Research of Supersonic Aircraft Low Sonic Boom Configuration Design and Optimizations

High noise level of sonic boom is one of the most important reasons that the supersonic transport can’t be applied to civil aviation broadly. Sonic boom is a complicated problem relating to aircraft configuration design, aerodynamics, acoustics and so on. The traditional sonic boom minimization theory is an inverse design method with single object, which makes it difficult to be applied in multi-objective optimization, effectively. For the low sonic boom configuration optimization, the sonic boom noise level prediction method based on supersonic linear theory was developed. The sonic boom level of a basic configuration of supersonic business jet was computed and the cause of formation of sonic boom was analyzed, based on which the fuse and wing plane wais optimized to decrease the noise level of sonic boom. Compared with the basic configuration, the sonic boom level of optimized configuration decreased distinctively, with the overpressure decreasing 41% and the A-weighted noise level decreasing 7.55 decibel. The aerodynamic characteristics of optimized configuration were computed. Compared with the basic configuration, the drag decreased obviously at the cruise condition without moment change.

Research of low boom and low drag supersonic aircraft design

Sonic boom reduction will be an issue of utmost importance in future supersonic transport, due to strong regulations on acoustic nuisance. The paper describes a new multi-objective optimization method for supersonic aircraft design. The method is developed by coupling Seebass–George–Darden (SGD) inverse design method and multi-objective genetic algorithm. Based on the method, different codes are developed. Using a computational architecture, a conceptual supersonic aircraft design environment (CSADE) is constructed. The architecture of CSADE includes inner optimization level and out optimization level. The low boom configuration is generated in inner optimization level by matching the target equivalent area distribution and actual equivalent area distribution. And low boom/low drag configuration is generated in outer optimization level by using NSGA-II multi-objective genetic algorithm to optimize the control parameters of SGD method and aircraft shape. Two objective functions, low sonic boom and low wave drag, are considered in CSADE. Physically reasonable Pareto solutions are obtained from the present optimization. Some supersonic aircraft configurations are selected from Pareto front and the optimization results indicate that the swept forward wing configuration has benefits in both sonic boom reduction and wave drag reduction. The results are validated by using computational fluid dynamics (CFD) analysis.

Design Decision Making and ICU Life Support Systems

What kind of evidence would help a design team confirm an important decision, such as the choice of a life support system for an intensive care unit? How can a research-informed or evidence-based design process assist in making such a decision? (Hamilton & Shepley, 2010)The design of a hospital intensive care unit (ICU) patient room, where critical care is provided to seriously ill patients by specialist physicians and nurses, is significantly influenced by the type of life support system chosen for the design, such as a headwall, power column, or overhead boom configuration (Hamilton, 1999; Hamilton & Ulrich, 2008). Why do designers and their clients choose one system over another? The decision often seems to be made based on familiarity with one system or another, or purely on cost. What evidence could be used in making this decision as part of a design project?The headwall model, in which the utilities and physiological monitors are locat- ed on the wall behind the head of the bed (see Figure 1), is the most common choice. Familiarity with this model may influence its use; it has been the prin- cipal system in ICUs since their beginning, when the ICU was an adaptation of the surgical recovery room model. Clinicians who have experienced only this model may understandably favor it. Another factor is that a headwall configu- ration can be the most economical choice. In the case of a crisis, or code blue situation, the bed must be pulled off the headwall to allow someone to stand behind the head to ensure that the patient's airway remains open. Difficulties for staff associated with stepping over lines and cords, and potentially disconnect- ing something important, is an inconvenience at best and a problem with serious health consequences at worst.The power column system is the second most common choice (see Figure 2). The power column is a vertical system, standing floor to ceiling, typically located diagonally off the head of the bed. It has connections for medical gasses, out- lets for electricity, and uninterrupted power. A power column has a bracket on which to mount the physiologic monitor, and usually includes baskets or shelves for necessary items. It often has an attached sphygmomanometer.More recently, ceiling-mounted boom systems have been introduced, with over- head swiveling pendants to support the monitor, gasses, electrical connections, and other utilities (see Figure 3). The overhead boom life support model is similar to a power column, except that it is not attached to the floor, and can be moved to different positions. The ceiling-mounted boom system can include a pair of booms, and thus a pair of pendants with utilities and other features.Because these different systems to deliver life support technologies perform in different ways, they influence staff activity and behaviors (Gallant, 2001), although comparisons are possible (Pati et al., 2008). Flexibility and adaptabil- ity increases as one moves from headwall to power column to overhead booms. The power column obviates the need to move the bed and the risk of umbilical disruption. The overhead boom in turn allows greater movement of the bed and multiple possible positioning options, as well as the ability to swing it out of the way when desired.If I were still in practice as a hospital architect, or in a consulting role for an organization involved in the design of a new critical care unit, I would consider the choice of a life support system to be a key design decision requiring serious attention. Sometimes the program of space requirements will include a specific square footage that may restrict the choice, but design of the patient room can- not be completed without this decision.I have suggested that identifying the key design issue and turning it into a researchable question is an early step in an evidence-based process. To do this we would need definitions of life support systems, identification of the various choices available, and an understanding of the uses to which such systems may be put. …

A modal disturbance estimator for vibration suppression in nonlinear flexible structures

This paper presents a control strategy for the suppression of vibration due to unknown disturbance forces in large, nonlinear flexible structures. The control action proposed, based on the modal approach, consists of two contributions. The first is the well-known Independent Modal-Space Control, which increases system damping and improves its behavior close to the resonance frequencies. The second is a disturbance estimator, which calculates the modal components of the external forces acting on the system and compensates for them using actuator forces. The system modal coordinates, required by both logics, are estimated through a modal state observer. The proposed control logic is tested on a flexible boom. The paper reports the numerical and experimental results both for the linear and nonlinear (large motion) boom configuration.

Efficacy of Aerial Spray Applications Using Fuselage Booms on Air Force C-130H Aircraft Against Mosquitoes and Biting Midges1

The effectiveness of a novel fuselage boom configuration was tested with flat-fan nozzles on U.S. Air Force C-130H aircraft to create ultra-low volume sprays to control mosquitoes (Culicidae) and biting midges (Ceratopogonidae). The mortality of mosquitoes and biting midges in bioassay cages and natural populations, using the organophosphate adulticide, naled, was measured. Mosquitoes in bioassay cages had 100% mortality at 639 m downwind in all single-pass spray trials, and most trials had >90% mortality up to 1491 m downwind. Mosquito mortality was negatively correlated with distance from the spray release point (r2 = 0.38, P < 0.001). The volume median diam of droplets collected was 44 tm at 213 m and decreased to 11 microm at 2130 m downwind of the release point. Droplet density decreased from an average of 18.4 drops/cm2 at 213 m to 2 drops/cm2 at 2130 m. Droplet densities of 10-18 droplets/cm2 were recorded at sampling stations with high mosquito mortality rates (>90%). In wide-area operational applications, numbers of mosquitoes from natural populations 1 wk postspray were 83% (range 55%-95%), lower than prespray numbers (P < 0.05). Biting midge numbers were reduced by 86% (range 53%-97%) on average (P = 0.051) after 7 days. The results of these field trials indicate that the fuselage boom configuration on C-130H aircraft are an effective method to conduct large-scale aerial sprays during military operations and public health emergencies.

The Effect of Boom Section and Nozzle Configuration on the Risk of Spray Drift

The effect of spray characteristics and boom section on spray drift produced by agricultural flat-fan nozzles has been investigated using wind-tunnel techniques. Variations in the effective spray plume porosity to an air stream were achieved by varying spray quality and varying nozzle spacing from 125 to 750 mm, in six steps. Three boom sections were used: astandard boom; a deep boom, for maximum air stream blockage, and a profile boom for reduced vertical dispersion. Wind speeds were varied from 1·0 and 3·0 m/s. Flow visualization techniques showed that the air stream pattern varied with plume porosity and mean air velocity. Measurements of airborne spray, 2 m downwind of the nozzles, showed that drift decreased as sprays changed in quality from fine to coarse using British Crop Protection Council scheme as expected. Maximum airborne drift occurred at a nozzle spacing of 500 mm with all spray qualities. Although the vertical profile of airborne drift was influenced by boom section, the magnitudes of difference between extremes of boom configuration were much less than changes due to nozzle characteristics. Variations in drift risk are characterized by the mean drift, mean drift moment and section moment, and could provide a mechanism for the assessment of various boom shapes and designs in combination with different nozzle conditions.

Evaluation of Beauveria Bassiana (Mycotrol® WP) with Pyrethroids for Control of Whitefly in Spring Cantaloupes

Abstract Cantaloupe, var. ‘Top Score,’ was planted in slant beds on 80-inch centers 17 February at Somerton, AZ. Plots were 4 rows by 25 feet long, with end buffers of 5 feet. Design was a RCB with 4 replicate plots per treatment. All materials were applied in 0.05% Silwet L77 spreader. Applications were started 18 May when whitefly numbers had reached 0.5 per cm2 of leaf. Additional sprays were made 1, 5, 9, 15 and 22 June. The first application was made at 40 gpa with a horizontal boom set with two drop nozzles (Dl/13 disc-core hollow cone) on each side directed towards the bed. The second application was made with a horizontal boom 4 inches over top of the row with 4 nozzles (Dl/13) at 16-inch intervals, directed downwards, delivering 40 gpa at 120 psi. For the third application, the number of nozzles was increased to seven per bed with a spacing of 4 inches; nozzles were alternately arranged forwards and backwards at about a 30 degree angle. Gpa was increased to 70, pressure decreased to 90 psi The final three sprays were made with the same boom configuration but used D2/33 full-cone nozzles delivering 100 gpa at 80 psi. Sprays were monitored by the use of water sensitive spray cards and coverslips mounted on leaf undersides in the melon plant canopy. Leaf samples were taken for nymphal counts on 15, 31 May, 10, 21, and 27 June. In each case 10 mid-crown leaves were collected per plot. Nymphs were counted in two 2.4 cm diameter discs taken from the basal areas of each leaf. Insect data were subjected to n transformation before ANOVA; means were separated by Tukey’s HSD Test (P=.05). Yields were determined on 28 June, 1995, by harvesting marketable melons from center two rows of each plot and grading by size.

Laboratory Testing of a Flexible Boom for Ice Management

Combatting oil spills in the Arctic is a major challenge. Drilling or producing oil or gas in the marginal ice zone (MIZ) may allow booms to be deployed upstream of an offshore structure to clear the water of ice, thereby enabling conventional oil spill countermeasures to be used. Such a boom would be kept in place by two ice-going service vessels or by moored buoys. SINTEF NHL and NRC have performed a number of small-scale tests with a flexible boom in the NRC ice basin in Ottawa. The purpose of the tests was to measure the effectiveness of using a flexible boom for collecting ice, and to determine the loads associated with collecting the ice. In the tests, various boom configurations were towed against a broken ice field consisting of ice pieces typically 50–100 mm across and 30 mm thick. The ice concentration was usually 10/10, but it was reduced to 8/10 and 5/10 for two tests. The boom was towed at speeds of 20 and 50 mm-s−1. Both the width of the boom and the slackness of the boom were varied over reasonable ranges. Two six-component dynamometers were used to support the boom. Thus, the force components on each end of the boom were measured. Further, two video cameras were used to record the effectiveness of each boom configuration. In this paper, the full results of this test program are presented and the application of the test results to the full-scale situation are discussed. The tests show that, under certain conditions, the use of boom is feasible for ice management in oil-contaminated water.

Diversion Oil Booms in Current

Diversion boom approaches are developed to contain oil spills close to shore when high‐current velocities prevent normal booming operations. In the diversion boom configuration, one end is anchored outside the spill, while the other is secured to shore. The boom is angled to the current to deflect the oil towards a shore pickup point. Boom configuration (planform shape) must be designed for each site‐specific current environment to prevent leakage under the boom. A mathematical model relating mooring points, boom parameters, and current is developed, calibrated, and validated. The model is applied, as a representative example, to the design of a boom configuration for the Northeast Petroleum terminal on the Piscataqua River, N.H. Current information is obtained, and trial configurations are evaluated employing the model and using a leakage criterion of 0.31 m/s (0.6 knots) for the maximum normal component of current. The recommended design is found to behave as predicted in a demonstration experiment (without oil). Thus, the model and design procedures are observed to be suitable for diversion configuration design in high‐speed currents.