Roughness of propeller blade surface and its implications for propulsion performance

Pustoshny, A.; Sverchkov, Andrey V.; Shevtsov, Sergey

doi:10.24937/2542-2324-2019-4-390-11-26

Cited by 6 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…На гребных винтах (ГВ) водоизмещающих судов очаги кавитационного износа возникают в концевых сечениях лопастей [2]. Очаг износа имеет грубую рваную поверхность, что оказывает отрицательное влияние на КПД движителя [3], и при обнаружении первых признаков кавитационного разрушения ГВ ремонтируют. Основной целью ремонта ГВ с очагами износа, расположенными в концевых сечениях лопастей, является восстановление качества поверхности, так как именно в этих районах лопастей данное качество имеет решающее значение для КПД ГВ [4].…”

Section: введение (Introduction)unclassified

Destruction mechanisms of epoxybased composite filled with metal powder under cavitation attack

Fiaktistov,

Tsvetkov,

Zaytseva

2023

jour

View full text Add to dashboard Cite

The samples of epoxy compound with a powder filler and without it are tested on cavitation wear. The powder of aluminum bronze BrAZhNMts9–4–4–1 is used as a filler. The powder is obtained by filing the rod of the bronze. The composition of the epoxy compound is 100 parts of the resin K‑153 plus 12 parts of the hardener (polyethylene epolyamine). The distribution of the bronze particles in the epoxy compound follows the law close to the exponential one, the average particle size is equal to approximately 27 μm, and the volume fraction of the bronze powder in the compound is about 9,5 percent. The tests are conducted using the ultrasonic magnetostrictve vibrator UZDN‑2T in fresh water of room temperature, the frequency and amplitude of the vibrator horn end equal to 22 kHz and 28 µm respectively. The distance between the horn end and the sample surface is 0,5 mm. During the experiments the wear of the samples is evaluated by their weighting on analytical scales with step-type indication of 0,1 mg, measuring the surface roughness and the microhardness of the bronze particles in the composite is carried out as well. It has been shown that the addition of the bronze particles into the epoxy compound not only changes the kinetics of cavitation wear of the polymer but also decreases its cavitation resistance. The decrease in cavitation resistance caused by bronze particles addition is attributed to the fact, that the boundary between a metal particle and epoxy matrix is a «weak» spot, and the destruction of polymer begins from this boundary area under cavitation attack.

show abstract

Section: введение (Introduction)unclassified

Destruction mechanisms of epoxybased composite filled with metal powder under cavitation attack

Fiaktistov,

Tsvetkov,

Zaytseva

2023

jour

View full text Add to dashboard Cite

show abstract

“…The use of polymeric compositions in machinery and ship repair is becoming more widespread [1], in particular, in restoration of cavitation wear spots on propeller blades (PB). On displacement vessels, cavitation wear occurs mostly in the blade tips [2], quality of the blade tips surface decreases considerably which, in its turn, negatively influences the propeller efficiency [3,4].…”

Section: Introductionmentioning

confidence: 99%

Model of the cavitation wear resistance of metal powder filled epoxy composites

Fiaktistov

Tsvetkov²,

Zaitseva³

2022

E3S Web Conf.

View full text Add to dashboard Cite

A powder-filled epoxy compound was tested for cavitation wear in the form of bronze particles BraZHNMc9-4-4-1. The particles were obtained by sawing a bronze bar. The composition of the compound was as follows: 100 parts of resin K-153 and 12 parts of hardener (polyethylene polyamine). The specimens were shaped as cylinders, 15.5 and 15 mm in diameter and height, respectively. The tests were carried out with an ultrasonic magnetostrictive vibrator in fresh water at water temperature 20 ± 3 ° C. The frequency and amplitude of oscillations of the vibrator hub end were approximately 22 kHz and 28 μm, respectively. The distance between the end of the concentrator and the end of the specimen wear was set to 0.5 mm. A second-order model describing the cavitation wear as a function of the bronze particle size, its content in the composite and the specific surface area of the particles was constructed by the least-squares method. The cavitation wear of the composite increases with increasing values of these parameters. The greatest influence on composite cavitation wear has the total surface area of bronze microparticles in volume unit.

show abstract

Influence of the bronze powder filler on the adhesion of epoxy compound to aluminum bronze

Tsvetkov,

Vihrov,

Fiaktistov

2024

jour

View full text Add to dashboard Cite

The tests to determine the adhesion of epoxy compound K-153, containing different amount of bronze powder, to aluminum bronze are carried out. As the bronze powder the filings, which are obtained by filing the rolled rod of bronze BrAZhNMts9-4-4-1, are used. The conventional size of the bronze particles amounts to 18 μm. The epoxy compositions are applied over the plates made out of BrAZhNMts9-4-4-1. The mentioned bronze is chosen as close analogue by composition to bronze BrA9Zh4N4L, used to cast ship propellers. The plates thickness is 4…5 mm, and the plates dimensions in plan are equal to approximately 50 by 100 mm. Before being coated the plates are ground with abrasive paper of different grain to obtain the arithmetical mean deviation of the surface profile equal to 0,5…0,900 μm. Coating the plates and aging the coatings are produced at temperature of 19±1 о С and ambient air relative humidity of 50±5 %. The average thickness of the coating amounts to 2,1 mm. The experiments are conducted after keeping the epoxy coating during 7 days. The tests are carried out according to the scheme, regulated by the GOST 32299-2013 "Paint materials. Pull-off test for adhesion". According to the scheme, metallic cylinders of the 19 mm diameter are stuck to the coating; preliminarily the spots of sticking are processed with abrasive cloth and solvent. Then the circular cuts are made in the coating around each cylinder and the cylinders are pulled off under the force directed perpendicularly to the coating, and the peel strength is recorded. The addition of bronze powder into the epoxy compound does not affect the peel strength that is the precipitation of the bronze particles in the epoxy compound during its hardening does not result in the decrease in the contact area of the epoxy resin with the bronze surface. This conclusion is confirmed by the calculation estimation: the calculated thickness of the resin layer in between a bronze particle and the plate surface after the completion of resin hardening is three orders of magnitude greater than the diane resin molecule size. It means that epoxy resin viscosity is too high, and the size and the mass of the particles are too small in order for the squeezing the resin, even partial, from under the particles takes place during the slow precipitation of the particles.

show abstract

Roughness of propeller blade surface and its implications for propulsion performance

Cited by 6 publications

References 0 publications

Destruction mechanisms of epoxybased composite filled with metal powder under cavitation attack

Destruction mechanisms of epoxybased composite filled with metal powder under cavitation attack

Model of the cavitation wear resistance of metal powder filled epoxy composites

Influence of the bronze powder filler on the adhesion of epoxy compound to aluminum bronze

Contact Info

Product

Resources

About