Nozzle Assembly Research Articles

The Effect of Hyperconjugation and Hydrogen Bonding on the Conformers of Methylated Monosaccharides.

The conformational landscapes of four 1-O-methylated monosaccharides-methyl a-glucose, methyl b-glucose, methyl a-galactose, and methyl b-galactose-were characterized using jet-cooled broadband rotational spectroscopy, supported by density functional theory calculations. A newly designed, simple pulsed nozzle assembly was used to introduced the sugar samples into a jet expansion without thermal degradation, eliminating the need for a complex and expensive laser ablation system. Ten conformers were experimentally identified by assigning their rotational spectra, and the intricate methyl internal rotation splittings were analysed. Notably, methylation alters the directionality of intramolecular hydrogen bonding of a-galactose highlighting its impact on structural preference. Natural bond orbital, intrinsic bond strength, and non-covalent interaction analyses were conducted to explore the interplay between hydrogen bonding and hyperconjugation. A set of σ to σ* neutral hyperconjugative interactions were found to override a strong hydrogen bond, driving a preference for the gauche conformers.

Ejectosome of Pectobacterium bacteriophage ΦM1.

Podophages that infect gram-negative bacteria, such as Pectobacterium pathogen ΦM1, encode tail assemblies too short to extend across the complex gram-negative cell wall. To overcome this, podophages encode a large protein complex (ejectosome) packaged inside the viral capsid and correspondingly ejected during infection to form a transient channel that spans the periplasmic space. Here, we describe the ejectosome of bacteriophage ΦM1 to a resolution of 3.32 Å by single-particle cryo-electron microscopy (cryo-EM). The core consists of tetrameric and octameric ejection proteins which form a ∼1.5-MDa ejectosome that must transition through the ∼30 Å aperture created by the short tail nozzle assembly that acts as the conduit for the passage of DNA during infection. The ejectosome forms several grooves into which coils of genomic DNA are fit before the DNA sharply turns and goes down the tunnel and into the portal. In addition, we reconstructed the icosahedral capsid and hybrid tail apparatus to resolutions between 3.04 and 3.23 Å, and note an uncommon fold adopted by the dimerized decoration proteins which further emphasize the structural diversity of podophages. These reconstructions have allowed the generation of a complete atomic model of the ΦM1, uncovering two distinct decoration proteins and highlighting the exquisite structural diversity of tailed bacteriophages.

Design of a Wind Tunnel Nozzle Section Trolley Control System Based on Backstepping Method

Abstract To accommodate different types of supersonic wind tunnel tests, frequent replacements of nozzle sections and test sections are required, involving multiple complex technical processes. To optimize operational procedures and improve efficiency, a control system for the wind tunnel nozzle section trolley based on the backstepping method was designed. The system uses radio frequency identification (RFID) signals for station positioning and intelligently adjusts the speed and direction of the control motor, thus driving the trolley to move back and forth automatically. Through the simulation of the motor motion control model, the system effectively reduces random disturbances in the motion system caused by load changes, achieves precise positioning of wind tunnel plugins and nozzle assemblies, enhances system operating accuracy, reduces production cycle times, and realizes a one-button positioning function for all components, playing a significant role in improving wind tunnel test efficiency and operational quality.

Simulation and experimental benchmarking of a proton pencil beam scanning nozzle model for development of MR-integrated proton therapy.

MR-integrated proton therapy is under development. It consists of the unique challenge of integrating a proton pencil beam scanning (PBS) beam line nozzle with an magnetic resonance imaging (MRI) scanner. The magnetic interaction between these two components is deemed high risk as the MR images can be degraded if there is cross-talk during beam delivery and imageacquisition. To create and benchmark a self-consistent proton PBS nozzle model for empowering the next stages of MR-integrated proton therapy development, namely exploring and de-risking complete integrated prototype system designs including magnetic shielding of the PBS nozzle. Magnetic field (COMSOL ) and radiation transport (Geant4) models of a proton PBS nozzle located at OncoRay (Dresden, Germany) were developed according to the manufacturers specifications. Geant4 simulations of the PBS process were performed by using magnetic field data generated by the COMSOL simulations. In total 315 spots were simulated which consisted of a scan pattern with 5cm spot spacings and for proton energies of 70, 100, 150, 200, and 220MeV. Analysis of the simulated deflection at the beam isocenter plane was performed to determine the self-consistency of the model. The magnetic fringe field from a sub selection of 24 of the 315 spot simulations were directly compared with high precision magnetometer measurements. These focused on the maximum scanning setting of 20cm beam deflection as generated from the second scanning magnet in the PBS for a proton beam energy of 220MeV. Locations along the beam line central axis (CAX) were measured at beam isocenter and downstream of 22, 47, 72, 97, and 122cm. Horizontal off-axis positions were measured at 22cm downstream of isocenter ( 50, 100, and 150cm from CAX). The proton PBS simulations had good spatial agreement to the theoretical values in all 315 spots examined at the beam line isocenter plane (0-2.9mm differences or within 1.5% of the local spot deflection amount). Careful analysis of the experimental measurements were able to isolate the changes in magnetic fields due solely to the scanning magnet contribution, and showed 1.9 1.2 -9.4 1.2 changes over the range of measurement locations. Direct comparison with the equivalent simulations matched within the measurement apparatus and setup uncertainty in all but one measurementpoint. For the first time a robust, accurate and self-consistent model of a proton PBS nozzle assembly has been created and successfully benchmarked for the purposes of advancing MR-integrated proton therapy research. The model will enable confidence in further simulation based work on fully integrated designs including MRI scanners and PBS nozzle magnetic shielding in order to de-risk and realize the full potential of MR-integrated proton therapy.

Research on thermodynamic modeling and temperature prediction of double flapper-nozzle servo valves

The thermal characteristic design of the aerospace servo valve is of significant importance due to the high temperature operating conditions. This paper aims to study the law of temperature variation of the internal chambers and shell of the servo valve while it is driven dynamically, in order to ensure that the components inside the servo valve work within an acceptable temperature range and avoid failure. This paper establishes thermodynamic models of the nozzle flapper assembly and the spool valve, as well as the whole servo valve, using the control volume method. The models consider the throttling heating generation of each throttling component in the servo valve and heat exchange between the shell and air. Based on these models, the temperature curves of the shell and oil in each chamber in the servo valve are simulated and analyzed, given a specified input signal. Finally, a test is conducted, and the results demonstrate that the temperature curve trend obtained through simulation and test is reasonable and more accurately reflects the internal temperature characteristics of servo valves. This research provides a reference for further studies on the internal heating mechanism of servo valves and the fault diagnosis of servo valves at high temperatures.

Design and Fabrication of a Bicycle Sprayer

The bicycle sprayer designed for crop spraying is a pragmatic and environmentally friendly choice for small-scale farmers, providing both effectiveness and long-term viability. Engineered to be attached on a regular bicycle, this device enables farmers to easily traverse fields and agricultural area with minimal physical effort. The sprayer features a 20-liter tank, suitable for small-scale farms, equipped with a slide-crank pumping system and a precision nozzle assembly to ensure efficient spraying. Made from lightweight and sturdy materials, it is both cost-efficient and highly portable. The rear wheel's rotation is converted into translation motion of the rod and pump by the use of a slider-crank reciprocating mechanism. The bicycle sprayer doubles as a mode of transportation for farmers or users traveling to and from the farm, enhancing its utility. The bicycle sprayer provides an environmentally-friendly option for small-scale farmers, enhancing crop productivity and minimizing the risks associated with liquid chemicals for farmers or operators. Based on the performance outcome, the recently created sprayer is capable of covering an area of one hectare in one hour. It demonstrates improved spray consistency and achieves a 75% efficiency rate, as confirmed through a sequence of tests conducted on specific farms.

Evaluation of the Thermal Diffusivity of Carbon/Phenolic Composites (CPCs) through Oxy-Acetylene Torch (OAT) Test-Part 1: Experimental Characterization and Preliminary Validation.

Carbon/Phenolic Composites (CPCs) are essential to manufacture many portions of the nozzle assembly of Solid Rocket Motors (SRMs) which are essential both to preserve the independent access to space as well as for the homeland security. In our research, a feasible approach aimed at preliminary retrieving the in-plane and out-plane thermal diffusivity of CPCs through the Oxy-Acetylene Torch (OAT) tests was validated. The proposed approach showed to be effective and able to bypass some limitations of common protocols, especially in terms of capability to determine the thermal diffusivity of CPCs at high heating rates. A comprehensive work of comparison of the obtained data with state-of-the-art CPCs such as MX-4926 and FM-5014 has also been carried out, evidencing the effectiveness of the proposed method.

Performance investigation of solar photovoltaic panels using mist nozzles cooling system

ABSTRACT Solar PV has a disadvantage over its many advantages that its electrical efficiency falls due to rise in surface/operating temperature of solar PV cells. Therefore, it is necessary to find a way to mitigate the efficiency loss due to rise in temperature as well as to increase life span of solar photovoltaics by lowering its cell temperature. In this research, the impact of mist cooling on output of PV panel is observed through experimental setup installed at rooftop of Postgraduate Department, Mehran University of Engineering and Technology, Jamshoro, Pakistan. The rear surface of PV module is cooled with designed mist nozzle assembly. The performance of modified mist cooled PV module is than compared with reference PV module. Experimental investigation is performed several days in different weather conditions with natural circulation and with forced circulations by using submerged pump. The maximum efficiency gains of 7% and average gain of 3.72% is observed with natural circulation, and maximum gain of 9.2% and average gain 1.72% are observed with forced circulated mist. The overall impact of proposed mist cooled system is positive on performance of PV panels.

Optimization of Solenoid Parameters for a Magnetic Nozzle Assembly Using Design of Experiments

Optimization of Solenoid Parameters for a Magnetic Nozzle Assembly Using Design of Experiments

Interlaminar properties, ablation resistance and thermal diffusivity of Carbon/Phenolic Composites (CPCs) derived from optimized high char yield matrices: A comparison with MX-4926 and FM-5014

Carbon/Phenolic Composites (CPCs) are used to manufacture many portions of the nozzle assembly of Solid Rocket Motors (SRMs) which are essential both to preserve the independent access to space as well as for the homeland security. In our research a new family of low cost, high char yield CPCs manufactured using ultra common raw materials - such as T300-like Polyacrylonitrile (PAN) based Carbon Fibers (PAN­CFs) - and having high values of Inter Laminar Shear Strength (ILSS) have been identified. Nanocomposite based CPCs were also produced. The interlaminar properties, ablation resistance and thermal diffusivity of the manufactured CPCs were studied. A unique and comprehensive work of comparison with state-of-the-art CPCs such as MX-4926 and FM-5014 has also been carried out evidencing the merits of the formulations produced in our work.

Numerical Simulation of Deformation in Hot Runner Manifold.

This study simulated the deformation of a hot runner manifold and nozzle assembly during operation, aiming to address potential leaks and premature failure. Both thermal and mechanical models were used simultaneously to accurately capture system behavior. A simplified set of boundary conditions was proposed for efficient problem-solving. Analysis of the simulation results revealed that thermal deformation posed a risk of catastrophic failures and leaks. Deformation from melt pressure was relatively small compared to thermal loading, not exceeding 12%. The study provided design recommendations based on the simulation findings, guiding the development of hot runner systems for improved reliability.

A miniaturized hydrogen flame ionization detector based on integrated nozzle assembly and embedded sealing structure

A modified miniaturized hydrogen flame ionization detector (m-FID) was developed and evaluated. An integrated nozzle assembly was constructed to solve the gas leakage caused by adhesive crack during repeated high-low temperature processes or vibration. An embedded sealing structure was designed to realize the face sealing, thus improving the sealing stability and reliability of the m-FID. Polyimide was employed as seal and insulation material to ensure the detector can be used at 300 °C for a long term. The hydrogen and air consumption of the m-FID was 12 mL/min and 110 mL/min, which is about 1/3 of the FID gas consumption of commercial laboratory instruments. The limit of detection (LOD) for n-hexadecane was 3.2 × 10−12 g/s, with a linear response range of nearly 5 orders of magnitude. Finally, it was installed onto an on-site gas chromatograph to detect drug samples with wide boiling point range from room temperature up to 535 °C.

Study on the Atomization Ability of the Annular Slit Nozzle Assembly with the Delivery Tube of Lower-limiting Flow

Study on the Atomization Ability of the Annular Slit Nozzle Assembly with the Delivery Tube of Lower-limiting Flow

An Optimization Analysis of the Melt-Cutting Diversion Jetting Mechanism for Downhole Drilling Columns

Summary Molten metal jet cutting, based on the transient superexothermic characteristics of aluminum thermal reaction, presents a novel technology for swiftly cutting and disposing of stuck drilling columns in downhole oil and gas wells. The key to achieving efficient cutting in drilling columns lies in the jetting mechanism, which guides the high-speed radial ejection of aluminum thermal reaction products that act upon the metal pipe wall. This study uses computational fluid dynamics (CFD) simulation to establish a fluid domain model for the process of cutting molten drilling columns. The optimization of the jetting mechanism is conducted to improve the circumferential coverage by the molten metal by analyzing the impact of molten metal yield and jetting mechanism parameters (cone angle of the conical conductor, diameter, number and length of nozzles, and shape of the diverter). Finally, an ejection test is carried out to verify the optimized jetting mechanism. Research results show that increasing the cone angle of the conical conductor can increase the flow rate of the molten metal at the upper end of the axial nozzle assembly to smoothly discharge the molten metal. Increasing the number of nozzles with equal diameters can increase the circumferential distribution range of molten metal ejected into the cutting area. However, the molten metal circumferential coverage will be impacted by increasing cutting distance. Increasing the nozzle size can reduce the divergence of the molten metal, thereby improving the coverage of the molten metal in the cutting area. When the nozzle arc length L = 8 mm, the molten metal can cover almost the entire cutting area. Adding a 2-mm horizontal draining table at the end of the diverter can assist the molten metal in changing its flow direction, allowing the molten metal to be ejected in a radial direction. The research results provide a theoretical basis for optimizing fusion cutting tools and formulating cutting processes.

Design, Analysis, and Development of Additive Manufacturing by using FDM Technique with Dual Nozzle Assembly

Traditional manufacturing is having limitations totackle Complex geometry and accuracy. To overcome this problem, additive manufacturing is an optimal solution for developing three-dimensional (3D) modelsbyusing thesuccessiveaddition of several layers. This paper has focused on overcoming the existing difficulties by the development of a dual nozzle 3D printer that would be used for additive manufacturing. In this research work, the conceptual design has been developed using Fusion 360TMand the detailed design is carriedout. Finally, the thermal analysis of the Nozzle head assembly has been carried out using ANSYS 16.0. A 3D printer has been developed to manufacture the prototype of a component. The total weight of the developed printer is reduced by 40% in comparison with the existing printer and the production rate is increased approximately by two times.In this research work, a 3D printer machine has been developed with an improved mechanism of a dual nozzle head assembly and guide ways.

Development and evaluation of a battery operated ginger (Zingiber officinale) washer for small and marginal farmers

Ginger (Zingiber officinale Rosc.) is a commercial crop grown for its aromatic rhizomes which is used both as a spice and medicine. Being a root crop and owing to its physical structure, ginger rhizomes contain heavy soil load which makes washing as an important and prime post-harvest operation. Manual washing of ginger is a laborious and time consuming process. An experiment was conducted at the ICAR-Indian Agricultural Research Institute, New Delhi during 2020 with an objective to develop a continuous rotary drum type battery operated ginger washer and to evaluate its performance.The machine consists of the frame, feeding and discharge chutes, rotary drum with internal flights, pressure pump and nozzle assembly, battery and a drive unit. The developed washer was evaluated at different feed rate and residence time to appraise the washing efficiency, microbial washing efficiency, bruise index and colour of washed ginger. Increase in feed rate significantly reduced the washing and microbial efficiencies but increased mechanical damage. Washing and microbial efficiencies increased with increase in residence time.Significant difference in the colour was found between washed and unwashed ginger.The best set of conditions under which the washer could be operated was 150 kg/h and 25 sec, at which the machine was found to have mechanical washing efficiency of 92.48%, microbial washing efficiency of 93.18% and 4.54% bruise index. Besides eliminating drudgery of washing operation, the developed washer was found to save time, water and operating cost as compared to manual washing.

Wernher Von Braun’s Pioneering Work in Modelling and Testing Liquid-Propellant Rockets

This paper presents a view on how Dr. Wernher Von Braun laid the basis for realistic modelling and testing liquid-propellants rockets, by his PhD Thesis – a secret document in 1934, which remained classified until 1960. Understanding that better mathematical modelling is needed if these rockets are to become spaceflight vehicles, he clarified in his thesis essential issues like: maximum achievable rocket speed; Laval nozzle thrust gain; polytropic processes in the combustion chamber and nozzle; influence of equilibrium and dissociation reactions; original measurement systems for rockets test stand; engineering solutions adequate for series production of the combustion chamber – reactive nozzle assembly. The thesis provided a theoretical and experimental basis for a new concept of the rocket, having a lightweight structure; low tanks pressure; high-pressure pumps and injectors; low start speed; rocket stabilization by gyroscopic means or by active jet controls; longer engine burning time; higher jet speed. Numerous tests made even with a fully assembled rocket (the “Aggregate-I”), improved mathematical model accuracy (e.g., the maximum achievable altitude predicted for the “Aggregate-II” rocket was confirmed later in-flight tests).

A New Inert Gas Delivery Design for Improved Shielding of Ladle Shroud–Collector Nozzle (LS–CN) Assembly: Modeling, Design, and Industrial‐Scale Validations

Argon injection in ladle shrouds is customarily practiced during the teeming of liquid steel from ladle to tundish to minimize air ingression and thereby restrict atmospheric oxidation of steel melt. Despite such practices, nitrogen pickup results in the tundish, implying inadequate shielding of ladle shroud–collector nozzle (LS–CN) joint. Accordingly, the efficacy of different argon injection designs in shrouds is evaluated in the present study, and thereby, a novel argon injection arrangement, embodying a twin, tangential gas discharge system, developed as a curative step to ensure maximum inertization of the LS–CN assembly. Numerical prediction of argon flow and distribution around the LS–CN assembly is accompanied by a homogeneous, non‐isothermal, two‐component turbulent flow model embodied in ANSYS Fluent. These, supported adequately by water modeling results, indicated that inertization of LS–CN assembly is considerably improved with the proposed design at argon flowrates typically practiced in industries (10 Nlit min−1). To substantiate laboratory findings, a plant‐scale investigation is carried out, wherein shrouds with a new gas delivery design are fabricated and deployed in continuous bloom casting operation in a special steel plant. Industrial trials confirm the superiority of the new design over existing ones and demonstrate a 50% reduction in nitrogen pickup, during teeming, under identical operating conditions.

Physical and Mathematical Modeling of Argon Flow and Distribution Around a Ladle Shroud-Collector Nozzle (LS-CN) Assembly

Physical and Mathematical Modeling of Argon Flow and Distribution Around a Ladle Shroud-Collector Nozzle (LS-CN) Assembly

Досвід впровадження адитивних технологій при ремонті деталей ГТД зі сплава ЕП 648 ВІ (ХН50ВМТЮБ-ВІ) в умовах серійного виробництва

Technology has been developed for repairing the nozzle assembly (SA) casing in the D-18T engine by additively growing the damaged part by microplasma surfacing with a powder of EP648VI (KhN50VMTYUB-VI) alloy. Traditionally, a part with such damage was rejected. The cost of replacing a damaged part with a new one is about 200 thousand hryvnias. The article discusses the equipment and features of the growing technology using the method of microplasma multilayer surfacing. Additive growth of the cut-damaged part was carried out on a STARWELD 190 H robotic installation for microplasma powder surfacing using EP648 VI alloy powders with a 63–163 micron fraction. After growing, heat treatment (aging at 700 ºС, exposure for 16 hours), mechanical processing, and quality control of the grown part were carried out. To create an evidence base to determine the possibility of installing a repaired part on the engine, a set of studies was carried out, which included the determination of the chemical composition of samples grown using a technology similar to repair, metallographic studies, and mechanical tests. As a result, it was found that the chemical composition of the deposited metal meets the requirements of the technical specifications TU 14-1-3046-97 "Bars made of heat-resistant alloy grade KhN50VMTYUB (EP648), and the microstructure of the deposited metal after heat treatment is a γ - solid solution with the presence of carbides, carbonitrides and a small amount of γ´ phase, which corresponds to the normally heat-treated state of the EP 648 VI (KhN50VMTYUB-VI) alloy and the level of mechanical properties of the grown alloy with subsequent serial heat treatment (aging at 700 ° C, holding for 16 hours) not lower than the level of the forging used at serial production of a part. The economic effect of the introduction of this technology is shown, which is more than 100 thousand hryvnias (about 23% of the cost of a new part).