A summary of acoustic characteristics and control techniques of underwater non-cavitation thruster

Ma, Chao

doi:10.1177/0954406219844530

Cited by 11 publications

(4 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The interaction of rotational motion and soil surface according to the soil dynamics against the tillage machine by considering the following factors such as tractor power (hp), maximum lateral force (N), cultivator gear speed (m / s), tractor power transmission efficiency (0.9 for simultaneous rotation and 0.8-0.9 for reverse rotation), soil resistance up to 0.7-0.8, rotation radius (mm) affecting tillage operations were investigated. This design was analyzed [24].…”

Section: Related Workmentioning

confidence: 99%

Using Different Angles of Rotating Blades Using the Finite Element Method

Ali Hassan,

Soheili Mehdizadeh

2024

View full text Add to dashboard Cite

One of the most important operations in agriculture is tillage, which has a great contribution to increasing crop yield and aeration of the soil and, ultimately, root development. Among the important tools for tillage are rotary rotators that are exposed to high and variable dynamic loads, so they are designed to have both the greatest contribution to soil agitation and high strength; It is necessary. Therefore, in this research, an L-shaped blade sample was designed for a rotator using a Biomimetic method. Due to the extensive research that has been done in the world in the field of manufacturing different types of rotators with a rotating agitator mechanism, therefore, it is necessary to study and optimize the rotator blades according to Iranian conditions. In this study, the studied variables include dependent and independent variables. Dependent variables include von Mises stress and arm displacement, and independent variables include the dimensions and geometric parameters of the Shape of the Rotator Blades. The idea for the blade design was inspired by the paw of a mole rat. Six blades were designed by simple method and biomimetic method and then by finite element method. Effects of blade angle change and design method on stress distribution, maximum displacement, maximum energy absorbed in the blade, reliability and under 400 N checked out. The results showed that in all designed models, the values of stress, displacement and energy absorbed were lower in the biomimetic design mode. As the blade angle increased, the values of the above parameters also decreased. Finally, the best model for having the least von Mises stress and the highest reliability was the blade with a Biomimetic design and a 20-degree angle.

show abstract

Section: Related Workmentioning

confidence: 99%

Using Different Angles of Rotating Blades Using the Finite Element Method

Ali Hassan,

Soheili Mehdizadeh

2024

View full text Add to dashboard Cite

show abstract

“…Compared with the complicated formation mechanism of aerodynamic noise, hydrodynamic noise has received less attention by scientists and researchers in the past. The acoustic characteristics of the pump 2 and underwater thruster 3 have become the hot research spot in the research field of hydrodynamic noise.…”

Section: Introductionmentioning

confidence: 99%

Effect of sleeve orifices ratio on flow performance and hydrodynamic noise in the two-stage sleeve control valve

Chen

Qiu

et al. 2022

Proceedings of the Institution of Mechanical Engineers, Part C:

View full text Add to dashboard Cite

Two-stage sleeve control valve has been widely implemented in high-pressure difference hydraulic system, whose function is to reduce hydrodynamic noise. The sleeve with orifices plays a significant role in reducing the hydrodynamic noise. The ratio of orifices diameter between outer sleeve and inner sleeve, Ri is investigated in this paper. The coupling effect of Ri on the flow field and hydrodynamic noise is analyzed deeply by URANS and FW-H model. Furthermore, the pressure, velocity, turbulent kinetic energy and sound pressure level of the flow field are monitored. The results indicate that higher Ri will restrict the flow velocity in the orifices, and the distributed pressure drop of two sleeves will be even. The velocity of flow in the outer sleeve reduces from 130 m/s to 90m/s with the increase of Ri. In addition, larger Ri can reduce the hydrodynamic noise and obtain higher flow capacity. When the Ri is 1.2, the sound power level distributes evenly in the gap, and the radiation intensity of the sound source is the smallest. The study can provide a reference for the design of sleeves in high-pressure control valves.

show abstract

“…The source of a marine propeller noise is an unsteady force that comprises a low-frequency Discrete-Spectrum (DS) force, caused by blade rotation in the incoming non-uniform flow, a low-frequency Broadband-Spectrum (BS) force, caused by the interaction between the blade and turbulent fluctuations, and a moderate-to-highfrequency BS force, caused by vortex shedding from the blade's trailing edge [1]. Compared to the moderate-to-high-frequency BS force, the low-frequency force exhibits high radiated energy [2], may cause considerable damage to the hull [2], has a long propagation distance [3] and can cause degradation of the marine biological environment [4]. The lowfrequency BS force can be predicted and controlled by combining spectral methods with optimisation algorithms.…”

Section: Introductionmentioning

confidence: 99%

“…The lowfrequency BS force can be predicted and controlled by combining spectral methods with optimisation algorithms. In contrast, low-frequency DS force, which is the primary signal used in the sonar-based detection and identification of ships [2,5], has been extensively researched to uncover its generation mechanism and develop control technologies, due to the considerable operational costs that arise from unsteady calculations.…”

Section: Introductionmentioning

confidence: 99%

Evolutionary Optimisation for Reduction of the Low-Frequency Discrete-Spectrum Force of Marine Propeller Based on a Data-Driven Surrogate Model

Jiang

Yang

Ren

et al. 2020

JMSE

View full text Add to dashboard Cite

For practical problems with non-convex, large-scale and highly constrained characteristics, evolutionary optimisation algorithms are widely used. However, advanced data-driven methods have yet to be comprehensively applied in related fields. In this study, a surrogate model combined with the Non-dominated Sorting Genetic Algorithm II-Differential Evolution (NSGA-II-DE) is applied to reduce the low-frequency Discrete-Spectrum (DS) force of propeller noise. Reduction of this force has drawn a lot of attention as it is the primary signal used in the sonar-based detection and identification of ships. In the present study, a surrogate model is proposed based on a trained Back-Propagation (BP) fully connected neural network, which improves the optimisation efficiency. The neural network is designed by analysing the depth and width of the hidden layers. The results indicate that a four-layer neural network with 64, 128, 256 and 64 nodes in each layer, respectively, exhibits the highest prediction accuracy. The prediction errors for the first order of DST, second order of DST and the thrust coefficient are only 0.21%, 5.71% and 0.01%, respectively. Data-Driven Evolutionary Optimisation (DDEO) is applied to a standard high-skew propeller to reduce DST. DDEO and a Traditional Evolutionary Optimisation Method (TEOM) obtain the same optimisation results, while the time cost of DDEO is only 0.68% that of the TEOM. Thus, the proposed DDEO is applicable to complex engineering problems in various fields.

show abstract

A summary of acoustic characteristics and control techniques of underwater non-cavitation thruster

Cited by 11 publications

References 28 publications

Using Different Angles of Rotating Blades Using the Finite Element Method

Using Different Angles of Rotating Blades Using the Finite Element Method

Effect of sleeve orifices ratio on flow performance and hydrodynamic noise in the two-stage sleeve control valve

Evolutionary Optimisation for Reduction of the Low-Frequency Discrete-Spectrum Force of Marine Propeller Based on a Data-Driven Surrogate Model

Contact Info

Product

Resources

About