NRC Publications Archive Archives des publications du CNRC

Frazil : a review of its properties, with a selected bibliography Williams, G. P.

This publication could be one of several versions: author’s original, accepted manuscript or the publisher’s version. / La version de cette publication peut être l’une des suivantes : la version prépublication de l’auteur, la version acceptée du manuscrit ou la version de l’éditeur.

Publisher’s version / Version de l'éditeur:

Engineering Journal, 42, 11, pp. 55-60, 1959-12-01

NRC Publications Record / Notice d'Archives des publications de CNRC: https://nrc-publications.canada.ca/eng/view/object/?id=f683a087-d82c-4542-81e8-398c95993824 https://publications-cnrc.canada.ca/fra/voir/objet/?id=f683a087-d82c-4542-81e8-398c95993824

Access and use of this website and the material on it are subject to the Terms and Conditions set forth at https://nrc-publications.canada.ca/eng/copyright READ THESE TERMS AND CONDITIONS CAREFULLY BEFORE USING THIS WEBSITE.

L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site https://publications-cnrc.canada.ca/fra/droits LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB.

Questions? Contact the NRC Publications Archive team at [email protected]. If you wish to email the authors directly, please see the first page of the publication for their contact information.

Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. Si vous n’arrivez pas à les repérer, communiquez avec nous à [email protected]. lt Ser TiIl l N21t2 NATIONAL RESEARCH COUNCIL CANADA

DIVISION OF BUILDING RESEARCH

FRAZIL ICE A Reuiewof its Propertieswith a SelectedBibliography

by

G. P. Williams

Ati Ai--t'i;i)

REPRINTED FROM

THE ENGINEERING IOURNAL voL. 42, NO. tt, NOVEMBER 1959,p.55-60

"':'iifioti?1'n TECHNICAL PAPER NO. 8T FEBr 1960 OF THE couRClL RltloNAL RESEARCH DIVISION OF BUILDING RESEARCH

OTTAWA PRICE IO CENTS DECEMRER T959 This publication is being distributed by the Division of Building Research of the National Research Council as a contribution towards better building in Canada. It should not tre reproduced in whole or in part, without permission of the original publisher. The Division would be glad to be of assistancein obtaining such permission.

Publications of the Division of Building Research may be 'obtained by mailing the appropriate remittance, (a Bank, Express, or Post Office Money Order or a cheque made payable at par in Ottawa, to the Receiver General of Canada, credit National Research Council) to the National Research Council, Ottawa. Stamps are not acceptable.

A coupon system has been introduced to make pavments for publica- tions relatively simple. Coupons are available in denominations of 5, 25, and 50 cents, and may be obtained by making a remittance as indicated above. These coupons may be used for the purchase of all National Research Council publications including specifications of the Canadian Government Specifica- tions Board.

jlililrl ililililil13 FRAZILICE

A Reuiew its Properties. "f With a SelectedBibliography

G. P. Williams Research Officer, and Ice Section, Dioisi,on of Bui'ldi'ng Research, National Research Council, Ottawa 2, Ont'

Tf-f HENEVER supercooledwater This report reviews the theory of frazil ice formation and the main factors l[/ vY rn reservolrs, lakes or rivers which cause- formations. The methods of forecasting ftazil ice and the design and also included. Although the frazil ice problem has comes in contact with hyd,ro-electric remedial considerations are been solved at many sites in Canada, this _review summarizes investigations which plant intakes, lvater supply intakes, would not generally be available to Canadian engineers. ilrigation and supply canals, there is a danger of serious clogging Theory of Formation face water exposed to the heat loss because of fuazil ice. Frazil ice oc- Ice is formed on the calm water will be interchanged with water from curring in large rivers is a naviga- of small lakes and stagnant pools lower depths so that a mass of water tional hazard and can be the cause when the loss of heat to the atmos- down to different depths, depending of serious ice jams. In Canada the phere by radiation, convection and on the degree of turbulence, will be work of Barnesl is the first major evaporation results in the supercool- cooled to 0"C without ice formation. effort to present detailed summaries ing of the surface water. In this If the cooling continues the water near will of available information on frazil ice static type of ice formation described the surface be supercooled hundredths degree (Alt- formation and occurrence. Since then by Devik2 the crystallization begins a few of a At in many investigations have been car- partly from matter on the beach berg3). a certain stage this frazil particles will ried out, notably in Russia and other and from solid material suspended supercooling, ice European countries. As no publica- or floating in the water. If the water start to form. tion is available in English, appar- remains at rest and the cooling con- In their early development, frazil ,circular ently, which summarizes these more tinues. a surface sheet of rap- ice particles are thin discs. recent developments, this survey of idly formed. Frequently, the particles are of ir- existing information on frazil ice has With dynamic ice formation as in regular outline but the edges are in- been prepared, accompanied by a running water or on the surface of variably rounded as shown in the ex- number of selected references. lake water disturbed bv wind. sur- cellent photographs by Schaefera. As growth proceeds, however, flat den- drites grow out from the edge of the eventually producing Fig. I Stagesin frazil ice formation. flat discs, the needle-like fragments commonly rec- ognized as frazil ice. Under favourable cooling,conditions these fragments STAGE I STAGE 4 rapidly form and group into the large spongy masses that cause so much SURFACE COOLING FURTHERCOOLING COOLING COOLING CONTINUES CONTINUES trouble on underwater installations. Figure I illustrates the different stages oO in frazil ice formation. Figure 2 shows TURBULENT some micro photographs of frazil ice [,lIXING in different stages of growth. A similar type of formation occurs in lake water when supercooling co- ooo inciding with stlong wave-action re- sults in agglomeration (Wilson5). HIGH CONCENTRATIONOF NEEDLE.LiKE CE NEEDLE S USTERSOF FRAZlL Even though the general nature of CIRCULARDISCOIDS DENDRITESGRO CLUSTERINGTO- ICE CONGLOMERATE flazil ice folmation has been known TORMfD OUT FROII DISCOIDSGETIIER FLOATING TO SURfACE AND BI]II-[]NG (JP ON fol a long time there is still argu- I]NDERWATER OBJECTS rnent and confusion in the literature Frazil ice particles floating on water Frazil ice particles changing shape Frazil ice particles growing and chang- surface. water surface. ing pattern at water surface. Fig. 2 Micro photographs of frazil ice in different stages of growth.

regarding the phenomenon (Timon- formation in water conclude that the the stream much the same as water- offo, LamborT). rate of growth of discoids (or frazil soaked leaves are carried underwater Supercooling atTd Nucleation. In- ice particles) is a function of the rate in a turbulent stream. vestigators seem to agree that super- of cooling of the water and the Schaefera estimates that the vol- cooled water often exists in streams for number of discoids. Their photo- ume concentration of frazil ice ao- long periods - even for days under graphs show clearly the development proaches 106 per cubic meter in h]is favourable conditions8. There is ar.- of circulal discoids into stellar crys- observations of frazil ice on the Mo- gument, however, regarding the tals. Their studies show that with hawk river in 1950. Frazil ice parti- amount of supercooling, although it supercooling from 0"C to -0.3"C, cles will adhere to each other and is generally assumed that it will rarely discoids and spicules are produced, also build up on underwater objects exceed .01"C in natural streams and and from -0.6'C to -0.9"C spicules causing many problems. According lakes (Schaefera).The theory of super'- only are produced. to Piotrovichlo, when water is super- cooUng is still a matter of some Much of the work done in recent cooled there is a strong increase disagreement. Dorseye indicates that years on the physics of supercooled in the cohesion forces between ice there are two theolies to explain the water droplets in the atmosphere is crystals and in the adhesion of ice freezing of water and the phenome- of relevant interest to investiqators crystals with stones, wood, metal and non of supercooling. In one, freez- of flazil ice (SchaeferrB). other objects in the water. Schaefer ing is considered to be initiated by Frazil lce Properties. The frazil ice suggests that the laminar type of certain aggregates of water molecules discoids vary in size. Schaefera ob- build-up indicates regelation between called ice molecules. The other theorv serves particles with a range of thick- these ice particles. considers freezing to begin ut ness 25 to 100 microns for particles Piotrovich also suggests that, as heterogeneous singularities, i.e., for- 1000 to 5000 microns in diameter. ice does not adhere strongly to cer- eign particles in the water which Hubbardla reports thickness almost tain substances as of purely serve as nuclei. Dorsey combines ele- identical to those reported by organic composition, these may be ments of both theories. He distin- Schaefer. Altberg3 ,claims that dis- used as coatings to protect against guishes between an embryo comprised coids up to several centimetres in underwater ice accumulations. Ac- of water molecules only, and a com- diameter could be grown artificially. cording to Murphyl6 waterwheels plex embryo with a foreign par.ticle Baylis and Gersteinl5 have observed protected by wooden racks are better as a centre to which molecules of particles that grow rapidly from Ya-in. able to withstand frazil attacks than water adhere. diameter up to 4 in. in diameter and those protected by iron racks, indi- Altberg3 believes that crystals do l/32 in. thick. cating a difference in the ability to not form in absolutely pure liquid The buoyancy of frazil ice parti- cohere between these two materials but only upon dust particles sus- cles is of particular practical interest. and ice. pended in the liquid. He concludes When the stream flow is not ex- One point that should be stressed that the ability of a liquid to crystal- tremely turbulent, frazil particles re- is that ice will not adhere to obiects lize depends upon the number of nu- main submerged and do not appear that are slightly above 32'F. This cleating centres per unit volume. to collect at the surface. Barnes at- is why the heating of underwater gate Piotrovichlo in a more recent studv. tempts to explain this phenomenon racks has often been successful in points out that in water with only-a in terms of viscosity and Stoke's reducing frazil ice accumulation. few hundredths o[ a degree of super.- Law8. Schaefera suggests that the Gale17 observes that freshly formed cooling, all ordinary inclusions are large ratio of major to minor axis frazil ice is "very sticky" and much inactive as crystallizing agents. and the small difference in specific more difficult to handle than frazil Kumai and Itagakil2 in their cin- gravity between jce and water cause rvhich has passed under surface ice erntrtoglaphic study of ice r:r.ystal the palticles to tumble about within and has not been subject to such str.ong ,.cooling. This suggeststha even slight increasesin t..""*p"."iur. may reduce considerablyth" ;jh;;;; ability of fr.azil ice.

#",H'"#i";;:f #i"l'" or coorins

ffi*T[if**'."fi,'"'',:un* *o-

Fig' :, 3 Factorsthat affect the rate of coolingofv' as sectionoau(rvrtofur rivernver The AMr water.wat( st. Lrtl::ffi"f"i$il*tt:?t"rt": oF FALLTNGsNow oR RA'N contain \\\\\\\\\\\\\\\.\\ formrfin-ormation "" in -:,,^*^ r .r . 'ittJt\t, in rivers. I" ;; .""i], Q rn, coNvEcrlvE cooLlNG the rate AMouNroF | \\\,.\[.,\ of co-olingttr"t #"; . -:"'' " I ur\rJ\\ pected from the differerrce""" aear caRRreo\ ri,ii,rtr ,/ f;;;, / EvAPORATTvE air temperature lNTo sec1oru\ ).p[ / >- cooltNc Sean u.td_-eun *"t"r

AMOUNT OF FLOATING ICE

AMOUIJT OF

*ateR losses ,rou.t-.*t \L, --ff--.|d from u *"t", r;,f;;;:"j"#

DE.REEo,',,",,.,".u ouri#";r'J.r,:l:i"l'+tilltilti which :",Jfii"T;ll Jlft,; indicateshoiv to"g lt will take river waier to cool to freezing tern- apparatus he was successful in meas- Some of the standard textbooks on perature, provided the mean air tem- uring the rate of temperature change hydro-electric design (Creager and perature is known or can be predicted. of river water and relating it to frazil Justins2) give general consideration It must be appreciated that these ice formations. His studies indicate to the design of hydlo plants to mini- formulae are necessarily very simpli- that frazil occurs only when the rate mize frazil ice conditions. fied presentations of a most complex of temperature change is greater than Loughlandza gives some general situation. From the theory it is diffi- 0.01'C/hr between temperatures of instructions for the desisn,of sluices cult to see how the wind velocity 0.1"C and 0'C. At temperatule and canals. including the suggestion terms can be ignored in any formula. changes less than 0.01'C/hr a natural that covering the flume will prevent It is apparent from Fig. 3 that there ice sheet is formed. Granbois in his snow from falling into the canal, are a large number of variables not paper gives a fairly complete des- thus reducing the rate at which the included in these formulae which cription of the resistance thermometer water cools. Carpenterss indicates might have important effects on the bulb, bridge and recorder which he that by coveling a flume and pro- rate of cooling of river water, used. viding an additional supply of stor- Baylis and Gersteinls state that, Anyone contemplating the field age water the frazil ice problem at "frazil ice formed under a wide var- measurement of river water temoera- the Barriere Hydro Plant in British iety of wind and air temperature ture near 32"F, however, *rrri b" Columbia could be overcome. conditions". Ruths2? mentions that, prepared for some problems. Perhaps In addition to the usual procedure "with air temperatures as low as the main difficulty to be overcome is of carefully surveying existing river -25"C -30"C or and no wind. that as soon as water falls below conditions, ensuring proper approach frazil ice will not always appear owing 0'C, ice begins to form on the tem- conditions and locatins the racks at to the presence of a heat insulating perature indicator.. The only tempera- a sufficient dcpth, metebrological fac- layer of moisture saturated air on ture then recorded is the freezins tors should not be neglected. For top of the water which rvill prevent point, even though there may bc example, care should be taken in the cold air from cooling the sur- supercooling present. Glanbois over- determining the prevailing wind di- face water to the critical tempera- came this by removing the detector rection, for if it prevails towards the fure". bulb after each successive run and intake channel large quantities of It also should be stressed that melting the ice from the indicator in ice will be for,ced into the channel. frazil ice is often produced a con- preparation for the next run. Even the direction of the wind rela- siderable distance upstream from the Devik2 measures the amount of tive to the flow of the river has a sections of the river under study; supercooling of the surface layer of varying effect on frazil ice produc- these geographical factors cannot be water with a "moll" thermooile. tion. A wind blowing upstream pro- ignored in any study. Murphyro, ttt Special precautions were taken re- duces more frazil than one blowing 1909 suggested that very large garding radiation effects, including downstream because of increased amounts of frazil ice develop in Lake the taking of measurements just be- surface agitation (Hendry3a). fore Deschenes, 3 to 4 miles upstream sunrise. Nybrant3l points out Once a rivel or canal is frozen from the rapids near the Hull power some of the problems of measuring over the rate of cooling is greatly plants water temperatures on the Ottawa river. under field con- redu,ced by the ice cover and the These complications do not mean ditions. He indicated that sensitive danger of large fraziT ice formations galvanometers that a practical means of predicting are difficult to use and is usually' eliminated. For this reason that it is the rate of cooling, and hence of necessary to keep a measur- considerable study has been made ing frazil ice formation, cannot be found. bridge at constant temperature of the r,r'ater velocities at which and to They do imply that site conditions check its calibration freouentlv. canals or livers will freeze. The fac- One must must be taken into consideration. also consider the stabiliiy tors affecting the formation of ice Standingzs gives some practical rules of the temperature sensing elements covers on rivers or canals are -affectgener- used at a particular plant for fore- and check their calibration fle- ally the same as those which quently. casting frazil ice as much as 12 hours the rate of cooling of a river or canal in advance. On a longer-term basis Although the work of Gr.anbois as shown in Fig. 3. Wardlaw2e calculates the mean indicates that it is possible to measure The St. Lawrence Waterway Pro- monthly heat losses from a water river water at temperatures around ject25 gives some practical informa- surface under winter conditions and 0'C to the necessary accuracy for tion on the relation between water obtains reasonable agreement with frazil ice predictions at a particular velocities and ice formation. Because other calculated values for heat losses site, special precautions and equip- velocity and turbulence of water are from open-water surfaces. ment are required which are usually only two factors which will affect not readily available for field installa- the formation of ice cover it tions. is not Forecasting Frazil Ice from Water possible to give limiting velocities Temperature Measurements which will apply in every case. In Design Considerations In some plants it is common prac- its report the Joint Board of Engi- tice to keep a record of water tem- Although it is not the purpose neers came to the general conclusion perature. Whenever the water temper- of this review to go into detail re- that "smooth ice covers may be ex- ature is near 32'F' and severe wind garding the design of canals, hydro pected to form in rivers with veloci- or temperature conditions are experi- intakes and racks for ice conditions, ties up to 1.25 ft/sec in zero weather enced, fi'azil ice formations may be some general comments on design are providing there is no high wind pre- expected. included in order to complete this venting such action". Granbois3o reports a method of general revjew. A comrhittee of the Power. Division precise water temperature measure- In 1919, Wilsonle stated that hy- of the A.S.C.E. investigated ice as ments with an electric resistance dro plants could be designed to be jt affects porvel plants and published thermometer and recorder. With his practically immune from ice troubles. a special report (Shenehon35).In ad- to a generally devices Appartenant au Bassin Baltique;-anii Inter- dition bibliography on the sub- severe, mechanical nitional Union of Geodesy Geo- ject, they give much information of to clean out intakes are used physics, International Association of Scientific Hydrology, 1948. pp. 367-379. use to design engineers. Some of the (Han yia). Murphyl6 reported in 8. Ice Formation in Open Water; Min- effects of ice on stream flow are of 1909 that frazil ice can be olevented nesata U. Engineeriirg Exp. Slation, July 1951. pp 104-107. (In Review of special interest to engineers design- by creating an artificial balrlier acloss the Propertres of Snolv and Ice, Edited by Homer T. Mantis. SIPRE Report ing canals or modifying river chan- the stream to start sulface ice forma- 4). 16 refs. nels under conditions (36' 37' tion. 9. Dorsey, N. E. The Freezing of Super- 38, 39, 40, 41). Cooled Water; Trans. of Amer. Philos. It has been suggested by Schaefer'{ Society, vol 38, Part 3, Nov. 1948. that the seeding of ponds with dry pp. 245-328. 10. Piotrovich, V. V. Formation of Depth- Remedial Action ice mieht hasten ice formation. Ice; Translated from Priroda, vol-. 9. Granboiiso reports limited success 1956, pp. 94-95, Defence Research For established power plants and Board, D S.I.S. Department of National by seeding river water with dry ice; Defence, Canada. T235R. hydraulic works, it is often possible 11 Arakawa, Kiyoshi. Experimental the resulting fragile ice sheet was Stu- to prevent the formation frazil dies on Freezing of Water; Interna- of destroyed as fast as it was formed. tional Union of Geodesy and Geo- ice by electrical heating. Reida2 gives physics, International Association of Lavrov55 considers that artificially Scientific Hydrology, 1954. pp. 474- some details of the heatinA rack- 477. of increasing the number of crystalliza- bars in hydro-electric planis, includ- 12. Kumai, M., and K. Itagaki. Cinemato- tion nuclei cannot be an effective graphic Study of Ice Crystal Forma- ing a formula for calculating the tion in Water; International Union of counter-rneasule because the in- Geoclesy and Geophysics, International power required. He emphasizes that tensity of underwater ice formation Association of Scienti.tic lrydrology, electric heating is of particular value 1954. pp. 463-467. depends on heat losses from the 13. Schaefer, V. J. The Formation of Ice in locations where frazil in develops stream, not on crystal number. the Laboratory and in the quickly and is not of Iong Atmosphere; International Union of duration. Additional lnformation The SIPRE Geodesy and Geophysics, International Ruths2? gives a table of electricai Association of Scientific Hydrology, biblioglaphy contains many useful 1948. pp. 186-209. values, including the power required, refelences on frazil ice and relaterd 14. Hubbard, Fran. When Winter Grips used in heating racks at several power Yosemite; Natural History vol 63, Dec. problems, including a series of Rus- 1954. pp. 448.-451 (illus.) houses in Norway. A report 15. Baylis, J. A. and H. II. cerstein. by the sian abstracts. A few selected Rus- subcommittee of the Hydraulic Fighting Frazil Ice at Waterworks; Power sian references have been chosen from Engineering News-Record, vol. 140, Committee for the Canadian Elec- no. 16, April 15, 1948. pp. 80-83. these abstracts and are listed as a - gives 16. Murphy, John. The Ice Question trical Associationa3 some details Bibliography. as it Affects Canadian Water Powers of the electrical utilized by - with Special References to Frazil I a Houille Blanche, (Numero 4, and Anchor fce; Proc. Trans. Roy. different companies"trergy in Soc. Can., 1909, section 3, pp. 143-U7. Canada for- juiilet, aoirt 1950) contains an excel- keeping gates 17. GaIe, G. Discussion of Paper by R. M. sluice free of ice. Var- lent review of snow and ice technical Wilson, Journal of Engineering Insti- ious other references are availabie, tute, vol. II, no. 5, 19f9. p. 392. terms in French and English. In ad- 18. Stakle, P. Frazil indicating that formations and Anchor-Ice in of frazil dition, this volume contains a general the Rivers of Latvia: International ice have been successfully combatteC Union oI Geodesy and Geophysics, review of frazil ice problems and International Association of Scientific l5' +0. bY electrical heating++' related phenomena. Hydrology, 1936, pp. 351-366. Steam heat has also 19. Wilson, R. M. Design of Hydro- been used for The Meteorological Abstracts and Electric Plants for Combatting Ice preventing ftazil ice formationa3. Troubles; J. Eng. Inst. Conn., vol. 2, Biblioglaphy of the A.M.S. for July 1919. pp. 283-395. DolionaT relates some of the difficul- and August 1956, contain an anno- 20.- Hoyt, W. G. The Effects of lce on ties connected with preventing ac- Stream Flow; U.S. Geol. Survey, tated bibliography on the micromete- Water Supply Paper 33fi f913. 77p. cumulations of frazil ice with steam orology of snow covers. This would 21. Geiger, R. The Climate Near the at a pump intake. Ground; Harvard University Press, be of value to anyone studying the 1950. 482p. jets Compressed air or air-bubbling thermal regime at snow and ice sur- 22. Powell, IM. M., and G. L. Clarke. The systems prevent Reflection and Absorption of Daylight to ice formation have faces. at the Surface of the Ocean; J. of the been applied for many years. Air Optiial Soc. of America, vol. 26, March This paper is a contribution of the 1936. bubbling systems depend on the fact Division of Building Research of the 23. Loughland, G. E. Ice Formations in that warm the Main Sierra Canal; Military En- water below the surfa,ce National Research Council of Canada. gineer, vol. 16, Nov. - Dec. 1924. can be brought to the surface by pp. 487-490. and is published with the approval 24. Atkins, W. R. G. and H. H. Poole. the rising air bubbles and so used to of the Director of the Division. The Photo-Electric Measurement of the Penetration of Lieht of Various prevent frazil ice at specific locations. Wave-Lengths into thd and the Skerretta8 in 1923 described how References Physiological Bearing of the Results; Trans. Roy. Soc. London (1935). jets of compressed air were utilized 1. Barnes, H. T. Ice Engineering; Renouf 25. St. Lawrence Waterway Project; Re- to prevent ice formation on gates of Publishing Co., Montreal, 1928. port of Joint Board of Engineers. Ice 2. Devik, Olaf. Supercooling and Ice For- Formation in the St. Lawrence and hydro-electric plants. In 1935 Sker- mation in Open ; International Other Rivers, Appendix E, (1924), Union of Geodesy and Geophysics, In- D.406. rettae gave sorne details of how ice ternational Association of Scientific 26. Wemelsfelder, P. J. An Investigation pp. Concerning the Balance of Heat in a pressure was prevented by air bub- Hvdrolosv, 1948.'fwenty 380-389. 3 Aitbere,-W. J. Years of Work River During Violent Frosu Interna- bling systems. Other more lecent in the Domain of Underwater Ice For- tional Union of Geodesy and Geo- mation (1915-1935); International Union Dhysics, International Association of papers are given by Owenso, Sim- of Geodesv and Geophvsics, Interna- Scientiftc Hydrology, 1945, pp. 191-197. monds51, and Granboiss2. Some fairly tional Ass

A list of all putrlications of the Division of Building Research is avail- able and may be obtained from the Publications Section, Division of Building Research, National Research Council, Ottawa, Canada.

ffi