PHrIiz ENG INE'ER ING LAB ORATORY

HYDHAULICS DIVISION

IvJ:Etmorandum No, M~12

F.L. Report No. 277-M~12

STATUS RE;POR~' OF RESEARCH PROJECT

ON

IMPROVING DESIGN OF A HOPPER DREDGE PUMP

Prepared by

J"ohn B. Herb ich

Prepared :for

U.S . ARMY EtfGINEER DISTRICT, PHILADELPHIA

Corps o:f Engineers

Philadelphia 29, Pennsylvania

Contract No. DA~36-109~CIVENG-59-1l2

May 1960

Bethlehem, Pennsylvania

CON TEN T S

1 0 INTRODuc'rrON .. 1

110 EXPERIMEWfAL STUDIES 0 o 1

III.. RECOMMENDA'l'IONS FOR IMPELLEt1 DESIGN CHANGES 2

IV 0 EXPERIMENTAL TEST PROGRAIVI 3

REFERENCES

APPENDIX •

4

6

STATUS REPORT OF RESEARCH PROJECT

ON

IMPROVING DESIGN OF A HOPPER DREDGE PUMP

I. INTRODUCTION

The following report summarizes the studies

performed during the month of April 1960, at the

Hydraulics Division of Fritz Engineering Laboratory,

under terms of Contract No. DA-36-109-CIVENG-59-112.

Earlier work was described in Status Reports dated:

December 1958(1)*, February 1959(2), April 1959(3),

June 1959(4), December 1959(6), February 1960(7),

March1960(9), April 1960(lq), and a Project Report

dated September 1959(5).

II. EXPERIMENTAL STUDIES

A. General Comments

Another test is planned to obtain pump charac­

teristics for silt-clay-water mixture concentrations

of about 1380 grams per liter. As the concentration

of mixture was only about 1320 grams per liter, some

additional amounts of heavily concentrated silt-clay

mixture were placed in the tank. It appears that the

mixtur~ concentration is still below the required

amount, and it will be allowed to settle to permit

the siphoning out of the clear water •

.. ..~~ Numbers in parentheses refer to References, page 4

B. Pre~sure Tests

Analysis pf pressure tests around periphery of

the volute taken during the previous months is under

way.

C. High=~:e~e~_t/rovingPi;:~~

Analysis of high-speed moying pictures taken

last year has been completed. A separate Memorandum

(Number' 1'1=11) is be ing prepared and ·will be submitted

to the Sponsor in June 1960.

III. RECOMMENDATIONS FOR IMPELLER DESIGN CHANGES

Design work on developing the vane profile

according to the logarithmic spiral and the involute

curve method is under way. The following impeller

vane designs were completed:

(1) Trial Design....!Shape of vane: involute curve

Entrance angle :: 45 degrees·

Exit angle :: 35 degrees

(2 ) 'Trial Design III

Shape of vane: logarithmic spiral

Entrance angle: 45 degrees

Exit angle: 35 degrees

(3) Trial Design rv

Shape of vane: logarithmic spiral

Entrance angle: 45 degrees

2

Exit angle: 22-1/2 degrees

Sketches of 'frial. Des1.gns I, III, ~nd rv,

are presented in th~ Appendix.

3

'~Tr,1., • EXPEH T1"1E1iflfAL 'T'E:S'r PBOGRAIV1

Clf;r! {:~ yll f11. C(Ylrl'fa.E: i1 t s_ ...,._,,·.:-"'_....'u......·.... ,.~, ..."'·.~, ..·.........·..,._,............-"....,,~_.

~[1he involute curve method (:[11'1a1 Design I)

'was ol'lg:Lrw,lly snggssted, 118 it was thought to be

the nlOS t r'1:1s.dily appllcab 1e method In the ease when

the entra!'we and exit angles have different values.

HOWfiver, It 1..j·as",als~ dlscov8T'sd that a logarithmlc

spiral ma:y a 1s 0 be clravHl in such a ca.se.

l1'h8 impeller vane o.f i],lrial Deslgn III'VJas

ordered ~)n April 28, ,1960, and deli,very was expect~

ed about June 1:,: 1960. (rrhls order was cancelled

on IVfay 13, 1960, following the Spons art s request).

The sketch showing Trlal Des ign IV was

f'orwa.l~ded to the Sponsor for appr'oval' on May 6,

1960.

()

(1) Herbich, J.Bo

4

REF ERE N C E S

STATUS REPORT OF RESEARCH PROJECT ONIMPROVING DESIGN OF A HOPPER DREDGEPUMP. Fritz Engineering Laboratory

Memorandum No. M-lLehigh University, December 1958

(2) Herb ich, J 013 0

(3) Herbich, JoB.

(4) Herb iqh, J";B.

,(5) Herbich, J".B.

(6) Herb ich, J.B.

(7) Herbich, J.B.Weiss, W.L.Waddingt on, vI.

(8) Weis~. W.L.

STATUS REPORT OF RESEARCH PROJECT ONIMPROVING DESIGN OF A HOPPER DREDGEPUMP. Fritz Engineering Laboratory

Memorandum No. M-2Lehigh University, February 1959

STATUS REPORT OF RESEARCH PROJECT ONIMPROVING DESIGN OF A HOPPER DREDGEPUMP. Fritz Engineering Laboratory

Memora~dum No. M- 3Lehigh University, April 1959

STATUS REPORT OF RESEARCH PROJECT ONIMPROVING D~SIGN OF A HOPPER DREDGEPUMP. Fritz Engineering Laboratory

Memorandum No. M~4

Lehigh University, June 1959

CHARACTERISTICS OF A MODEL DREDGE PUMPFritz Engineering LaboratoryProject Report No. 31Lehigh University, September 1959

STATUS REPORT OF RESEARCH PROJECT ONIMPROVING DESIGN OF A HOPPER DREDGEPUMP. Fritz Engineering Laboratory

Memorandum No.M,:,,5Lehigh University, December 1959

STATUS REPORT OF RESEARCH PROJECT ONIMPROVING DESIGN OF A HOPPER DREDGEPUMP. Fritz Engineering Laboratory

Memorandum No. M-6Lehigh Univer~ity, February-1960

SUGGESTED DESIGN CHANGES FOR ACENTRIFUGAL PUMP IMPELLERa~NDLING DREDGED MUD

Fritz Engineering LaboratorySpecial ReportLehigh Univers i ty, November -1959

References (c0nc1uded) 5

(9) Herbich, J.B. STATUS REPORT OF RESEARCH PROJECT ONIMPROVING DESIGN OF A HOPPER DREDGEPUMP. Fritz Engineering Laboratory

Memorandum No. M-8Lehigh University, March 1960

(10) Herbich, J .•B. STATUS REPORT OF RESEARCH PROJECT ONIMPROVING DESIGN OF A HOPPER DREDGEPUMP. Fritz Engineering L~boratory

Memorandum No. M-9 'Lehigh University, April 1960

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