general hammer v8 xm

5/23/2018 General Hammer v8 Xm

1/6

General HAMMER V8 XM [FAQ]

Rate This

Document Information

Document Type:FAQ

Product!":Bentley HAMMER

Ver!#on!":V8 XM

$r#%#nal Aut&or:Jesse Drinoli! Bentley Technical "u##ort $rou#

%an I o#en &ater$EM"'%AD V8 XM mo(els)

*es+ HAMMER V8 XM uses the same file format as &ater$EM" an( &ater%AD V8 XM! so you can

(irectly o#en the files+ All , #rorams con-eniently use a +.t an( +.t+m(/ file to store the mo(el (ata+

&hat is HAMMER0s calculation enine /ase( u#on)

HAMMER uses the Metho( 1f %haracteristics+

&hat 2in( of (eman(s shoul( /e use( as the initialcon(itions of a transient simulation)

Ty#ically! you shoul( run a transient simulation for the ma3imum an( minimum (eman( hours for each of

the (e-elo#ment con(itions 4net.or2 an( (eman( #oints5 un(er consi(eration+

Are #i#e /en(s 4-erte3es5 use( in the force calculations)

6o! currently they are not consi(ere(+ If you nee( to stu(y the effects of transient forces 4X'*'75 on a #i#e

.ith -erte3es! you shoul( consi(er re#lacin the /en(s 4-erte3es5 .ith unctions+

&hen I create a ra#h un(er Vie. 9 $ra#hs! this seems toonly sho. the initial con(itions+ &here can I -ie. (etaile(ra#hical results of the transient simulation)

The transient results are -ie.e( in the Transient Results Vie.er! locate( un(er the Analysis menu+ The

amount of results inclu(e( in here is (etermine( /y the re#ort #erio(! re#ort #oints an( :enerate

animation (ata: settins! un(er Analysis 9 %alculation 1#tions 9 Transient calculation o#tion


2/6

Ho. (o you (efine the startin con(itions of the transientsimulation)

The startin con(itions of the mo(el /efore a transient occurs are (efine( in one of t.o .ays+ First! you

can in-o2e the &ater$EM" stea(y state sol-er 4Analysis 9 %om#ute initial con(itions5 to calculate themfor you! /ase( on the (eman(s! /oun(ary con(itions an( other element attri/utes+ This is the same sol-er

that Bentley &ater%AD an( &ater$EM" use+ The transient sol-er then uses the com#ute( flo.s an(

hy(raulic ra(es as the startin con(itions+

Alternati-ely! you can (efine your o.n startin con(itions 4flo. an( hea(5 /y choosin :true: for the

attri/ute calle( :s#ecify initial con(itions): in the transient calculation o#tions 4Analysis 9 %alculation

o#tions+5 &hen (oin this! the transient sol-er .ill no loner use the hea('flo. com#ute( /y the :com#ute

initial con(itions:! /ut instea( .ill use the hea( an( flo. -alues that you must enter in! in the :transient

4initial5: section of each element0s #ro#erties+ 6ote that if you .ant to slihtly mo(ify some com#ute( initial

con(itions! you can co#y them o-er to the user (efine( initial con(itions fiel(s first /y usin the :co#y initial

con(itions: tool 4un(er the Tools menu5 an( then alter them as you see fit+

Ho. can I -ie. e3ten(e( transient results! such as #um#s#ee(! air flo. of a %AV! as -olume of a hy(ro#neumatictan2! etc! for each timeste#)

First! enter a num/er for the :Re#ort #erio(: attri/ute of an element+ This re#resents ho. often the results

.ill /e sa-e( for+ For e3am#le! a re#ort #erio( of 0;


3/6

5 "et u# a line ra#h .ith the a##ro#riate columns 4Time! #lus .hate-er attri/ute you0( li2e to ra#h+ For

e3am#le! -olume of air for a hy(ro#neumatic tan25

I am usin F%V! RV an( "V -al-es in my mo(el! /ut they

(o not seem to /e .or2in (urin the transient simulation!#er the settin I ha-e entere(+ &hy)

The #ressure re(ucin ' #ressure sustainin ' f lo. control #ro#erties of these -al-es are only use( (urin

the initial con(itions calculation+ This is /ecause HAMMER assumes that (urin the transient e-ent! these

-al-es cannot react Cuic2ly enouh to the chanes in flo.'#ressure+ If you are runnin a lon transient

simulation an( nee( to mo(el the effects of these -al-es! you0ll nee( to use an o#eratin rule on the -al-e

to close them+

%an you use sim#le or loical controls (urin the transient

simulation)6o! the controls that you enter un(er %om#onents 9 %ontrols only a##ly to the initial con(itions calculation+

To control elements (urin the transient simulation! you0ll nee( to use confiuration in the in(i-i(ual

eCui#ment 4such as closure time for the chec2 -al-e no(e5 or o#eratin rules 4such as the #attern of time

-s+ relati-e closure for a -al-e5+

I ha-e entere( controls un(er %om#onents 9 %ontrols /utthey (o not seem to /e .or2in (urin my transientsimulation+ &hy)

These controls only a##ly to the initial con(itions calculations 4stea(y state or E"5! not the transient

simulation+ If you nee( to control thins (urin the transient! you must use the o#tions seen in the

#ro#erties of the -arious transient elements+ For e3am#le! an o#eratin rule for a T%V -al-e or the time

(elay until shut(o.n for a #um#+

&hat (oes the follo.in user notification mean! an( .hat isthe (e-iation /ase( on) :&AR6I6$ The .a-es#ee( orlenth a##ro3imations (e-iate e3cessi-ely from the entere(

-alues+ enthen short #i#es an('or su/(i-i(e loner#i#es+:

The (e-iation mentione( here is /ase( on a #ercentae! .hich you can see /y the units! un(er analysis 9

transient timeste# o#tions+

Basically! /ase( on the time ste#! Hammer tries to ha-e a .a-e /e a/le to tra-el from one en( of the #i#e

to the other en( in e-en multi#les of the time ste#+ Therefore! Hammer .ill try to a(ust the lenth of the

#i#e to allo. this to ha##en+ By (efault! if it has to a(ust the lenth more than G or @


4/6

u(ment+ *ou can certainly ma2e some a(ustments! o /ac2 to the Timeste#s! clic2 the u#(ate /utton

an( see the ne. ma3'mean a(ustment+ *ou can also chane the timeste# as #re-iously mentione( an(

chec2 the ne. ma3'mean usin the same u#(ate /utton as .ell as choose /et.een a(ustin .a-e s#ee(

or lenth+ Ty#ically this is ust a tra(eoff /et.een accuracy an( run time+ The smaller you ma2e the

timeste#! the /etter the accuracy 4less a(ustment .ill nee( to /e ma(e5! /ut the loner the transient run

.ill ta2e to com#lete+

For more information! see 'entley Tec&n#cal (upport )no*led%e'a!e+

Ho. can I fin( &ater Deceleration in a i#eline .ith achec2 -al-e)

First! run the Initial %on(ition analysis an( recor( the -elocity in the #i#e (o.nstream of the chec2 -al-e+

et0s assume it is ? ft'secon(+

6e3t! run the transient simulation an( o#en the Transient Results Vie.er+ lot a time history ra#h of flo.in the #i#e (o.nstream of the chec2 -al-e an( measure the time from .hen the #um# turns off until the

flo. cur-e crosses the 3a3is 4i+e+ .hen flo. reaches ero5+ et0s assume it is = secon(s+

"o the (eceleration of the .ater column is ? ft'secon( ' = secon(s K = ft'sL=+

This is an a-erae (eceleration rate! .hich is ty#ically .hat -al-e manufacturers #ro-i(e+

Ho. (oes the Transient Results Vie.er .or2 an( ho. can Iuse it to -ie. my results)

The Transient Results Vie.er (is#lays transient results in ra#h form an( also can animate hy(raulic

ra(e in a #rofile+

The :aths 4rofiles5: #ull(o.n at the to# allo.s you to select a #rofile 4(efine( in the main user interface

un(er Vie. 9 rofiles5 an( then either #lot or animate it+ The :#lot: .ill #ro-i(e the minimum'ma3imum

transient en-elo#e+ The :animate: /utton .ill allo. you to see the hy(raulic ra(e #rofile as it chanes

o-er time+ This is useful to un(erstan( ho. certain transient in(ucin e-ents affect the system as a .hole+

If the animate /utton is raye( out! ma2e sure :enerate animate (ata: is set to :true:! in your transient

calculation o#tions+ To re(uce the amount of #rofiles a-aila/le! o to Vie. 9 rofiles! riht clic2 on the

ones you0( li2e to omit from the transient results -ie.er an( (eselect :transient re#ort #ath:+

The :Time Histories: #ull(o.n at the /ottom of the Transient Results Vie.er (is#lays en( #oints that are

a-aila/le to ra#h+ The amount of en(#oints liste( are (etermine( /y the :re#ort #oints: o#tion in the

transient calculation o#tions+ 6ote that transient simulation results are a-aila/le at the en(s of the #i#es

.here they meet a no(e element+ For e3am#le! the u#stream si(e of a #i#e or the (o.nstream si(e of a

#um#+ For time histories! you can #lot the hea(! #ressure! flo.! air'-a#or -olume an( force 4if you0-e

chosen to com#ute transient force+5

&hat (o the (ifferent colore( lines in a transient results-ie.er #rofile re#resent)

In eneral! you can riht clic2 on the frame'a3is of the #lotte( #rofile! select :format (ata: an( see the

names of the -arious #lotte( lines in the (ro#(o.n+
http://appsnet.bentley.com/kbase/http://appsnet.bentley.com/kbase/http://appsnet.bentley.com/kbase/


5/6

For an animate( #rofile! chec2 the /elo. (iaram

For a #lotte( hea( en-elo#e

"oli( /lac2 line #hysical ele-ations

Dashe( /lac2 line 4or soli( orane line if a #ressure #lot5 Initial con(itions hea(

"oli( re( line ma3imum transient hea(

Dashe( /lue line Minimum transient hea(

Re( line at to# Ma3 -a#or'air -olume

Dashe( yello. line -a#or #ressure 4as a reference5

Ho. can I a(( a ne. material such as HDE to the materialli/rary)

;+ $o to %om#onents 9 Enineerin i/raries an( clic2 the #lus sin ne3t to :Material i/raries:

=+ Riht clic2 Materiali/rary+3ml an( choose :a(( item: a ne. material entry .ill a##ear at the

/ottom of the list+

,+ Riht clic2 this ne. material entry! choose rename an( enter the name 4such as 0HDE05+

?+ 1n the riht si(e! enter the friction coefficients! *oun0s Mo(ulus an( oisson0s ratio for your ne.

material! then clic2 close+


6/6

Note: The Young's Modulus and Poisson's ratio are only necessary if you need

to use the automatic wave speed calculator tool, under Tools > Wave peed

!alculator"

If you .oul( li2e to create a ne. enineerin li/rary 43ml file5 instea( of alterin the (efault

Materiali/rary+3ml! sim#ly riht clic2 on :Material i/raries:! choose :create li/rary:! choose a location tosa-e the file! then re#eat ste#s =? a/o-e! re#lacin 0Materiali/rary+3ml0 .ith the name of your li/rary+

&hat is the (ifference /et.een the :Ele-ation: an(:Ele-ation 4inlet'outlet in-ert5: fiel(s in the #ro#erties of areser-oir)

The :Ele-ation: re#resents the .ater surface ele-ation an( the :Ele-ation 4inlet'outlet in-ert5: re#resents

the in-ert of the #i#e that attaches the reser-oir to the system+ ressure at the reser-oir location is

(etermine( /y the (ifference /et.een these -alues+

Ho. can I mo(el a shut after time (elay #um# that hasneither a chec2 -al-e or control -al-e)

&hen usin :shut (o.n after time (elay: transient #um# ty#e! you must select either :control -al-e: or

:chec2 -al-e: as the um# -al-e ty#e+ If you (o not .ant a chec2 -al-e or control -al-e! select :%ontrol

Val-e: As the #um# -al-e ty#e an( enter a lare num/er such as secon(s! as the :Time 4For

Val-e to %lose5:+

Ho. can I #lot multi#le time histories in the same ra#h ormulti#le #rofile #lots on the same #rofile)

6ati-ely there is no (irect .ay to (o this .ith the Transient Results Vie.er+ Ho.e-er! you can (o it usin

the /elo. #rocess+ This is useful in cases .here you0( li2e to com#are transient #rofile'time series results

/et.een scenarios+

;5 1#en time history ra#h 4or #rofile #lot5 num/er ;

=5 Riht clic2 in the mi((le of the ra#h an( choose "a-e As 9 HAMMER ra#h sa-e the +r# file

some.here

,5 %lose ra#h 4or #rofile #lot5 num/er ; an( o to File 9 o#en an( reo#en it

?5 Riht clic2 on the frame of the ra#h an( choose :co#y (ata:@5 1#en ra#h 4or #rofile #lot5 num/er =! riht clic2 on the frame an( choose :#aste (ata 4G5:+

6ote you may ha-e to a(ust the * a3is scale if the #aste( (ata (oesn0t fit in ra#h num/er =+

general hammer v8 xm

Documents