Hydrodynamics & Acoustics Newsletter #3

Krylov Shipbuilding Institute
Develops Ventilated Water Jet and
Use of Gas Cavities to Reduce Hull Friction


This is a portion of a U.S. Navy European Technology Newsletter

Newsletter 96-003
18 June 1996
Dr Peter Majumdar

Krylov Shipbuilding Research Institute, St Petersburg, Russia: An Update

2. Summary

Present newsletter provides an update on the home of Russian ship research, the Krylov Shipbuilding Research Institute (KSRI), based on my visit of its facilities on 14 and 15 May, 1996.

3. Background

The Krylov Shipbuilding and Research Institute, which celebrated its centenary two years ago, had been established in 1893 as a towing tank facility for ship resistance and powering research--just as the US Navy's Carderock Division of Naval Surface Warfare Center began as the Experimental Model Basin (EMB) about the same time. Much the same way as Carderock, KSRI soon became a world leader in fundamental and applied research in the fields of ship hydrodynamics, acoustics, structures, and related systems. During the 1940s this research center was named after Krylov, a pioneer in mathematical formulation of ship wave resistance mechanisms.

Today, research in ship and propulsor hydrodynamics still dominates the activity at KSRI. The facility in this area comprises a deep water towing tank, a shallow water towing tank, a high-speed towing tank, a seakeeping and maneuvering basin, a rotating-arm basin, five propulsor cavitation tunnels, a cavitation basin, an ice model basin, a wind tunnel, and a number of test units for pressure vessels.

4. Research Emphasis Today

4.1.1 High Speed Marine Propulsors

Propulsors requiring special features for dynamically-supported high speed marine vehicles have in the recent years received special attention throughout the world. The principal challenge in the design of such a propulsor is in attaining a high efficiency at low speeds. KSRI's most notable development in this area has been that of the Ventilated Waterjet Propulsor. The design-point efficiency of this propulsor has been shown to be higher than that of a subcavitating propeller. However, ventilated waterjets do have a problem in providing a steady craft acceleration at intermediate speeds, which can be corrected by means of an active system modifying blade hydrodynamics instantaneously. However, this problem can also be alleviated through design modifications allowing the propulsor to operate in different hydrodynamic regimes at different speeds. There does exist considerable interest among the KSRI scientists and management in a US-Russian collaborative effort for further research on this concept.

4.1.2 Ship Resistance Reduction by Gas Cavities on Hull Surface

This is a KSRI concept towards which considerable effort is expended today both in theoretical research and in towing-tank measurements for empirical parameters. Conceptually, this approach applies and maintains a gas film separating a large part of the ship bottom from hull boundary layer, thereby eliminating the associated skin-friction drag. First introduced more than a century ago, implementation of this concept has so far not been possible because of the instability of such a gas film. Beginning with a two-dimensional development of theory and its experimental validation, KSRI has extended this concept to three-dimensional hull forms and obtained rather promising preliminary model test results. There is no particular interest on the part of KSRI at this time to extend this project into a collaborative effort.

5. Further Details

For further details on some of the above projects at KSRI one can contact

Dr P. Peter Majumdar
Office of Naval Research Europe
223 Old Marylebone Road
London NW1 5TH, UK

Telephone: +44-171-514-4947
Fax: +44-171-723-6359
E-Mail: PMajumdar@onreur.navy.mil

For general information on KSRI as well as its specific projects one can contact

Dr Alexandre P. Pylaev
Deputy Director and Commercial Marketing Manager
Krylov Shipbuilding Research Institute
St Petersburg, Russia

Telephone: +7-812-127-96-47
Fax: +7-812-127-95-94

Copies of this and other ONR Europe newsletters are obtainable from the World-Wide Web by reaching

http://www.ehis.navy.mil/

6. US Government Disclaimer

The opinions and assessments in this report are solely those of the author and do not necessarily reflect the official US Government, US Navy, or ONREUR positions.


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