Propeller Type Research Articles

Experimental study on liquid distribution in a vane type propellant tank

Propellant tank is used to store the propellant in propulsion system. Propellant management device (PMD) is the key component in propellant tank to manage the liquid propellant under zero gravity. A microgravity drop tower test system was established to investigate the performance of PMD. A kind of vane type propellant tank was used for the drop tower test. Single module was used for experiment tests, and the microgravity level wass between 10-2g0 and 10-3g0. The anhydrous ethanol is used as analogue liquid. Different volume fraction of liquid were used to study influence of the PMD on the management performance. Changes of gas-liquid interface during the test are studied. Velocities flow along the vane of different liquid volume fraction in the tank are different at the beginning (t<0.8s). The liquid reorientation time is 0.8s when the liquid volume fraction is larger than 10%. The liquid reorientation time is prolong when the liquid volume fraction is less than 10%. The liquid climbing height along vane under microgravity increases as the volume fraction of liquid reduces. Experimental results provide a favorable reference for further optimization design of vane type propellant tank.

Computational study on the effect of the shape of ducts on the performance of the submarine propeller

With the tremendous growth of science and technology in the world, the silent submarine has been an interesting research topic for many years. What is of equal interest is how to produce a high-speed submarine that limits noise to minimise detection from the enemy. In this study, we investigated the combination of a propeller and a duct so that when a submarine is operated, it minimises as much as possible the noise without affecting the speed of the submarine. The goal of installing the duct outside the propeller is to reduce the noise and loss of thrust simultaneously. The purpose of this article is to investigate the variation of the magnitude of the noise and thrust that occurs when a submarine propeller is operated in six different types of ducts. The research method is to use the large eddy simulation method with the cavitation model and then to calculate the result using the finite volume method. The study found that Ducts 1 and 4 have a better noise reduction effect and better propulsion than the other four ducts. Among them, Duct 4 has the best noise reduction effect, and Duct 1 provides the maximum propulsion. In all of the computation examples herein, the cavitation phenomenon did not occur. In the future, we will continue to study the growth and decline of related physical quantities with various types of propellers and ducts.

Heat of Formation of ADN‐Based Liquid Monopropellants

AbstractEnergetic ionic liquids have obtained substantial attention the last decades as less toxic, or green, monopropellants to replace the carcinogenic and toxic hydrazine. Among the most promising hydrazine substitutes are propellants based on ammonium dinitramide, ADN, dissolved in a fuel/water mixture. These types of propellants are single phase mixtures, and thus their heats of formation are influenced by the heats of solution and heats of mixing of the respective components used. These enthalpy contributions have been measured for three different ADN‐based propellants (LMP‐103S, FLP‐106 and FLP‐107) and their specific impulses have been calculated. The results show that ADN heat of solution must be considered in order to accurately calculate the specific impulse.

New Nature-Inspired Cycloidal Propeller for Low-Reynolds-Number Hovering Flight

A new type of pivoting-blade cycloidal propeller, which can equip aircraft with vertical take-off and landing capability, is presented in this paper. This propeller has the appearance of damselfly wings and the advantage of low mass compared with other types developed to date. The operating mode shows similarities with the movement of these insects’ wings to generate upward vertical thrust. To cover the range of Reynolds number from 2250 to 25,000, propellers with 70 and 200 mm blades were constructed. Using the blade element theory, a simplified two-dimensional mathematical model was developed to predict thrust, power, and hovering efficiency. Experiments were performed to validate that model for the case of hovering flight. Quantitatively, the results of the experiments match the prediction produced by the two-dimensional mathematical model very well. The theoretical analysis proves that both lift and drag contribute to the net vertical force, and the contribution of drag is at least 50%. This way of generating vectored thrust is emerging as an alternative solution to other types of propulsion in low-Reynolds-number regimes with a blade tip Mach number not greater than 0.2.

Computational Study on the Steady Loading Noise of Drone Propellers: Noise Source Modeling with the Lattice Boltzmann Method

In the present study, a new computational methodology is explored to compute the acoustic field of drone propellers using noise source modeling with the lattice Boltzmann method. A simple mathematical model of steady loading noise for predicting the blade passing frequency (BPF) tone and harmonics at low frequencies (100–1000 Hz) is proposed and tested for various types of drone propellers. The computed result is in a reasonably good agreement with NASA’s measured sound pressure level (SPL) for APC-SF and DJI-CF two-blade single drone propellers rotating at 3600–6000 revolutions per minute. It replicates well the feature of an even number of BPF harmonics for the tested model propellers, showing the decaying slope of $$-\,6$$ for the first two BPF and harmonic peaks in the SPL spectrum. Notably, the proposed steady loading noise model shows all components of RPS harmonics with different magnitudes for different blade sizes and rotor arrangements, such as tricopter and quadcopter. The proposed method can be used for predicting and analyzing tones at low frequencies for various types of open rotor systems, such as multicopters and distributed electric propulsion vehicles.

Pengaruh Kebisingan Dalam Ruang Control Tower Terhadap Pelayanan Lalulintas Penerbangan Di Bandara Sentani Jayapura

In the provision of air traffic services, ATC (Air Traffic Controller) officers are requiredto ensure safety and smoothness in accordance with the procedures for flight safety can beachieved. The case of Kelas I Khusus Sentani Jayapura Airport is the noise caused by theapron building which is quite close to the tower building and the propeller type plane thatpasses the bravo taxiway causing quite disturbing noise. The purpose of this research is toprovide optimal air traffic service related to controller comfort in providing flight trafficservice, using qualitative deskriktif method based on field observation and related documenton air transport service provision in order to create flight safety and security. The results ofthis paper indicate that noise can affect the convenience of the controller when providing airtraffic services in terms of safety and regularity of the flight. It is suggested to AIRNAV andKelas I Khusus Sentani Jayapura Airport managers should install carpet and rubber silencerin tower building to reduce noise.

RANCANG BANGUN DAN UJI KELAYAKAN PEMBANGKIT LISTRIK TENAGA PICOHYDRO TIPE PROPELLER

South Sulawesi is an area which has abundant hydro energy. Thus allowing the construction of hydro power plant. According to Perusahaan Listrik Negara (PLN) in 2012, South Sulawesi has 72.22% electrification ratio. It shows that there are 27.78% areas of South Sulawesi which have not supplied by electricity. To overcome this, a pico-scale independent power plant is required. Propeller type of picohydro power plant is one of the hydro power plants that can be used in unsupllied areas . This type of plant requires only 2-10 m head so that it has a wide coverage area usage. Beside that, it is very easy in maintenance and simple in construction. Seeing this, picohydro power plant’s design and proper test is important to do as a solution for the people in an unsupplied area. Based on design and proper test , a hydro power plant with 180 mm diameter turbine tap and 55 mm diameter turbine hub, 4 turbine blades and 7 % as the highest system efficiency is constructed.

Ceiling Effects for Hybrid Aerial–Surface Locomotion of Small Rotorcraft

As platform size is reduced, the flight of aerial robots becomes increasingly energetically expensive. Limitations on payload and endurance of these small robots have prompted researchers to explore the use of bimodal aerial-surface locomotion as a strategy to prolong operation time while retaining a high vantage point. In this work, we propose the use of ``ceiling effects'' as a power conserving strategy for small rotorcraft to perch on an overhang. In the vicinity of a ceiling, spinning propellers generate markedly higher thrust. To understand the observed aerodynamic phenomena}, momentum theory and blade element method are employed to describe the thrust, power, and rotational rate of spinning propellers in terms of propeller-to-ceiling distance. The models, which take into account the influence of neighboring propellers as present in multirotor vehicles, are verified using two propeller types 23-mm and 50-mm radii in various configurations on a benchtop setup. The results are consistent with the proposed models. In proximity to the ceiling, power consumption of propellers with 23-mm radius arranged in a quadrotor configuration was found to reduce by a factor of three. To this end, we present a conceptual prototype that demonstrates the use of ceiling effects for perching maneuvers. Overall, the promising outcomes highlight possible uses of ceiling effects for efficient bimodal locomotion in small multirotor vehicles

Effect of Antioxidant on Storage Performance and Life Prediction of HTPB Propellant

In order to study the aging property of HTPB propellant in storage and the effect of antioxidant on the storage life of propellant, accelerated aging tests were carried out for two types of propellant. A non-linear aging model was introduced into the classical Arrhenius equation, and the starting point of aging was modified. With the maximum elongation as the evaluation parameter, the storage life at 25 °C is 9.6 years with the critical value is 20%, and the storage life is 17.5 years with the critical value is 15%. By controlling the content of antioxidant in propellant, the formula of type I propellant was modified, and the life of propellant after modification was predicted. The storage life is 12.4 years at 25 °C with the critical value is 20%, and the storage life of propellant is 21.3 years when the critical value is 15%. It was proved that the storage life of propellant could be effectively improved by controlling the content of antioxidant.

COMPARISON OF PROPELLER TYPE B-SERIES AND AU-OUTLINE GAWN SERIES FOR IMPROVING ON SUBMARINE PROPULSION PERFORMANCE USING CFD

Submarine propeller need some unique criteria can give bigger amount of thrust with noiseless. The submarine propeller design must able to produce the high thrust value, low pressure value, and smooth propeller streamline. This study investigates and compares some type of propeller that are B – 7 series, B – 8 series, Au – 7 Outline gawn series, and Au – 8 outline gawn series with some different parameters, that is blade diameter, number of blades, skew angle and pitch. From some models that have been compared, the best propeller is B – 8 series on 500 rpm with thrust value 25481 N, torque value 3927 Nm, average value pressure about 10608,92 Pa, and turbulent flow with average value velocity stream under 14,33 m/s.

Towards Understanding of Polymorphism of the G-rich Region of Human Papillomavirus Type 52.

The potential to affect gene expression via G-quadruplex stabilization has been extended to all domains of life, including viruses. Here, we investigate the polymorphism and structures of G-quadruplexes of the human papillomavirus type 52 with UV, CD and NMR spectroscopy and gel electrophoresis. We show that oligonucleotide with five G-tracts folds into several structures and that naturally occurring single nucleotide polymorphisms (SNPs) have profound effects on the structural polymorphism in the context of G-quadruplex forming propensity, conformational heterogeneity and folding stability. With help of SNP analysis, we were able to select one of the predominant forms, formed by G-rich sequence d(G3TAG3CAG4ACACAG3T). This oligonucleotide termed HPV52(1–4) adopts a three G-quartet snap back (3 + 1) type scaffold with four syn guanine residues, two edgewise loops spanning the same groove, a no-residue V loop and a propeller type loop. The first guanine residue is incorporated in the central G-quartet and all four-guanine residues from G4 stretch are included in the three quartet G-quadruplex core. Modification studies identified several structural elements that are important for stabilization of the described G-quadruplex fold. Our results expand set of G-rich targets in viral genomes and address the fundamental questions regarding folding of G-rich sequences.

Research Overview of Amphibious Platform Driving Device

Amphibious vehicles are mainly equipped with water driving devices on the land driving system, which can be divided into caterpillar type, propeller type, water-jet type and air-jet type. The universal drive mode avoids two sets of devices and is simple in structure. The rotating surface vector thruster is designed to drive the amphibious platform in an amphibious way, which can sail from the water to the water. On the basis of this, the impeller driven device of baffle plate is subtracted from hub, and the baffle is added to reduce weight and improve efficiency.

Formation of solid residues in combustion of boron-containing solid propellants

Boron-containing solid propellants are promising propellants for ducted rockets. The experimental data show that combustion of boron-containing propellants is accompanied by an intense conglomeration of the boron particles near the burning surface. As a result, the boron particles conglomerates which are the branched coral structures composed of sintered boron particles are formed in combustion of boron-containing solid propellants. This results in decrease in combustion efficiency of ducted rockets. To calculate the ignition and combustion of a conglomerate in the secondary combustor of a ducted rocket, it is necessary to know the size, structure and shape of the boron particle conglomerates that can significantly affect these processes. In this paper, we consider a model and a method for calculating the boron particles conglomeration in combustion of the boron-containing solid propellants. The process of the boron particles conglomeration is considered as a result of competition between two main processes: the formation of adhesive bonds between the contacting boron particles and rupture of these bonds under the action of the aerodynamic detached force from the side the flow of gaseous combustion products of solid propellant. The criterion of formation of residues (slag) on the burning surface of boron-containing propellants is considered. It is shown that depending on the propellant burning rate law, two different types of propellants with different conglomeration behavior can exist. The results of calculations of the boron particles conglomeration which demonstrate the slag formation are shown.

A numerical study on performance improvement of counter-rotating type tidal stream power unit

One of the forms of ocean energy, tidal stream energy is attracting attention as a sustainable, predictable and eco-friendly ocean energy source. Unique tandem propellers that can counter-rotate have been designed to generate electric power effectively from a tidal stream. This type of power unit has several advantages compared to the conventional unit with a single propeller and the increase in efficiency of counter-rotating type tidal stream power unit has already been proven. The counter-rotating type tidal stream power unit has a complex interrelationship between the front and rear propeller contrary to the conventional single propeller type tidal turbine. Such as, the no-load area on the front propeller, the diameter ratio of front and rear propeller and the rotational speed of each propeller, etc.. And the inlet condition of the rear propeller is very important to improve the efficiency. Thus, we have to consider these parameters to optimize tidal stream power unit. In this research, the numerical optimization algorithm with response surface method and adaptive single-objective optimization method are applied to obtain desirable propeller performance.

An angle speed and thrust relationship of the rotor system in the quadcopter aircraft

Utilizing Quadcopter were still many obstacles such as; plane easy to fall; the battery is not durable; vulnerable to weather conditions and others. The research and development has grown to improve aircraft facilities and capabilities. Many parameters related to aircraft lift capability factors; fly long; flying high; type of motor; the type of propeller: including the sensors and control systems used. This study was to find the relationship between changes in the BLDC motor voltage source to the rotor angle velocity &lt;em&gt;(ω)&lt;/em&gt;; rotor speed to rotor lift &lt;em&gt;(Ft)&lt;/em&gt;; wind speed to rotor lift; push the following rotor &lt;em&gt;(Ct)&lt;/em&gt;. Empirical testing was conducted in the laboratory to find the relationship of these parameters. The results data show that; the lift power generated with rotational speed was not proportional, non linearity occurs when the rotor was released from the self and starts pulling the strain gauge when the rotation speed reaches around 65 &lt;em&gt;rps&lt;/em&gt;. Once the rotation speed of the rotor is able to reach up to 1.5 Newton lift then the thrust rising trend sharply&lt;strong&gt; &lt;/strong&gt;increasing &lt;strong&gt;to&lt;/strong&gt;increasing &lt;strong&gt;of &lt;/strong&gt;the rotor speed. A motor hade 1200 &lt;em&gt;KV&lt;/em&gt; and blade with a radius of 0.12 &lt;em&gt;m&lt;/em&gt;, then obtained thrust &lt;em&gt;(Ct)&lt;/em&gt; of 1.732.

Expanding production regions of α-form and β-form glycine using an antisolvent crystallization method assisted by N2 fine bubbles

To develop a crystallization technique that can enhance the production of metastable α-form and unstable β-form glycine, we studied the antisolvent crystallization of glycine using the gas–liquid interfaces around N2 fine bubbles as novel crystallization fields. In the regions near the gas–liquid interfaces, local supersaturation is generated because of the accumulation of glycine and alcohol as an antisolvent as a result of the negative electric charge on the fine bubble surface. Hence, the produced glycine polymorphs change from the stable γ-form to a α-form or β-form glycine. Additionally, local supersaturation at the gas–liquid interfaces can be expected to change via modification of the accumulation of the glycine and alcohol molecules and the interaction of glycine-water-alcohol with the different alcohol additives. At a solution temperature of 303 K, methanol (MeOH), ethanol (EtOH), or isopropanol (IPA) as an antisolvent were rapidly mixed into the saturated glycine solution. While mixing MeOH, EtOH, or IPA with the saturated glycine solution, N2 fine bubbles with an average size of 10 µm were continuously supplied to the mixed solution using a self-supporting bubble generator and a glycine polymorph was crystallized within 5 min. For comparison, an antisolvent crystallization free of N2 fine bubbles was conducted using a propeller type mixer. During antisolvent crystallization with/without fine bubble injection, the additional alcohol volume was varied to control the generation rate of the supersaturation in the bulk solution (rC/CS). Consequently, the production regions of the α-form and β-form glycine were broadened to lower rC/CS via N2 fine bubble injection. The expansion behavior for α-form or β-form glycine significantly increased because of the enhancement of local supersaturation at the regions near the gas–liquid interfaces of the N2 fine bubbles owing to the decreasing carbon number in the alcohol.

Cascade Optimization of an Axial-Flow Hydraulic Turbine Type Propeller by a Genetic Algorithm

Cascade Optimization of an Axial-Flow Hydraulic Turbine Type Propeller by a Genetic Algorithm

An angle velocity of blade and lift force relationship of the single rotor system

Problems in utilizing Quadcopter, either as a hobby or as special needs are still many obstacles or weaknesses such as; plane easy to fall; plane easy hit; the battery is not durable; vulnerable to weather conditions and others. In this regard, Quadcopter's research and development has grown to include weaknesses of existing Quadcopter planes and to improve aircraft facilities and capabilities. In developing the knowledge and information about the Quadcopter aircraft, the data or parameters related to aircraft lift capability factors; fly long; flying high; type of motor used; the type of propeller used; including the sensors and control systems used. Thus, this study was to find the relationship between changes in the BLDC motor voltage source to the rotor angle velocity (ω); Change of rotor speed to wind velocity through rotor (v); change of rotor speed to rotor lift (Ft); change of wind speed to rotor lift; push the following rotor (Ct). In this study, empirical testing was conducted in the laboratory to determine the relationship among others: changes in the BLDC motor voltage source to the rotor angle velocity (ω); Change of rotor speed to wind velocity through rotor (v); change of rotor speed to rotor lift (Ft); change of wind speed to rotor lift; push the following rotor (Ct). Test and measurement results data show that; the relationship between lift power generated with rotational speed is not proportional Nonlinearity occurs when the rotor is released from the self and starts pulling the strain gauge when the rotation speed reaches around 65 rps. Once the rotation speed of the rotor is able to reach up to 1.5 Newton lift then the thrust rising trend increasing sharply to the increasing the speed of rotation of the rotor. A special rotor that has BLDC motor specifications such as; 1200 KV, 5 Volt and 30 Ampere; blade with a radius of r 0.12 m; at a temperature of about 27 o C; in the condition there are no other wind currents then obtained thrust (Ct) of 1.732. Keywords: Rotation Speed, Thrust Coefficient, Quadcopter.

РАЗРАБОТКА ТРЕХМЕРНОЙ МОДЕЛИ ОСЕВОГО ВОДОМЕТА В ПРОГРАММЕ SOLIDWORKS

The article provides a brief description of the construction of the main parts of the three-dimensional model of the axial water jet, followed by their Assembly into the finished product. The role of computer simulation in the design of complex types of propellers, which include water jet, is shown. The possibility of solving problems of hydrodynamics with the help of "SolidWorks"is demonstrated. The design of the water jet pipe, taking into account the absence of cavitation. The urgency of application of three-dimensional modeling in the field of shipbuilding, using CAD-programs of machine-building orientation is shown.

The effect of fuel on the energy consumption and production of greenhouse gases in transport

Nowadays, the environmental aspects of transport are very actual issues, mainly the energy consumption and GHG production. The priority of EU transport strategy is to decrease the negative environmental impacts of all transport modes. The article discusses the calculation of the energy consumption and production of greenhouse gases in transport from both the primary and secondary points of view. This means, that it reflects the implications on the environment not only while operating the vehicle, but also during production, refining, distribution and storage of the fuel used in transport. The calculation is done by using the methodology of the standard EN 16 258:2012. This standard is used on all cars using various types of propellants. The results of the calculation show in a non-discriminatory manner the energy effectiveness of the individual types of fuel, as well as the rate of their production of greenhouse gases expressed in a comparison unit of equivalent CO2e.