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 Especially useful for finding the maximum reaction at aft block. ``` `Especially useful for finding the maximum reaction at aft block. `***This run file works best if the GF file origin is located at the bow `***This run uses CRTPT(1) to set the draft, it will be overwritem if ` previously defined `***This run file allows two series of longitudinal CL blocks so that two ` different spacings can be used. `***This run file allows only one side block per side. clear `proj tanker0`set the project name to be the same as your GF filename read tanker0`Read geometry report {project} ` User Input `============================= `Set Initial Ship Condition `--------------------------- lbp 5, 95`assign the forward and aft draft locations `Set the waterplane by entering drafts or lightship weight `->Be sure to select the correct solve method below (after the macros) draft 5.5 @ FP, 6.10 @ AP`Set initial drafts `WEIGHT = 64.5 @ 0, 65.7 @ 95`Or set initial weight distribution `weight = 128@0, 128@24, 0@24, 0@71 130@71, 129@95 `weight report /profile vcg 5`Estimated VCG `Enter block locations and other data `------------------------------------- variable la, lf, lb dl1, dl2, m, n, n1, n2, s, sz, ns, ls, ts, vs set la = 88`Location of aftmost block from origin (see geometry file) set lf = 8`Location of foremost block from origin (see geometry file) set lb = {la} minus {lf} set n = 20 `Max number of blocks set n1 = 3`Number of blocks in first series set dl1 = 10`Spacing between blocks (aftmost series) set n2 = 3`Number of blocks in second series set dl2 = 20`Spacing between blocks (second series) `Note: n1 + n2 < n-2 (n-2 accounts for side blocks set ls = 58`Side Block long. location from GF origin set ts = 3.5`Side Block transverse location from CL set vs = 0.0`Side Block vertical point of contact above ship's BL set m = .10`Increase this number to increase penetration (deformation) `higher for less stiffness, more penetration `In this example, penetration is block deformation `m = 0.2 typical value used for grounding calc, values varies `depending upon length of vessel and soil condition, etc. set ns = 15`Number of steps to report for drydocking evolution set sz = 0.5 `Step size factor (increase for larger steps) `Trim divided by 15 (arbitrary factor), this factor is used `in conjunction with "ns" factor set s = 0`.003`Dock floor slope (tangent of angle, positive = aft trim) ` End of User Input `================================= variable l,p,dl,dp,x,t,stepnum set x = 0`initialize variable used to set height of the ship set stepnum = 1 `initialize variable used to report the step number macro mk_block set l = {la} set dl = {dl1} set s = tan {trim} minus {s} ` if {s} < 0 then \Error: Trim must be greater | REPORT OFF | END .blocks ({n1}) `Makes first (aftmost) series of aft blocks set l = {l} plus {dl} set dl = {dl2} set l = {l} minus {dl} if {n2} > 0 then .blocks ({n2}) `Makes second series of aft blocks .block {ls} {ts} {vs} "Stbd Side " `Make side blocks set ts = minus {ts} .block {ls} {ts} {vs} "Port Side " / macro block`Creates a ground point to model a block if {n} = 0 then exit | \ Error: Increase number of blocks, n. set t = %1 minus {la} set p = {s} times {t} ground "%4Block @ %1" * %1 %2 %3 /pen: {p} {m} set n = {n} minus 1 / macro blocks`Calls macro block to create a series .block {l} 0 0 set l = {l} minus {dl} / macro mk_point part hull ref {la} 0 0`Define reference point at the location of the aft block set t = minus {height} crtpt (1) "Tracking pt." {la}, 0, {t} `Used to adjust waterplane `REF 0 0 0 part off / macro status`Report macro status displ:total, wpl:total `status ground `use this Cmd for simplified report ground report `use this Cmd for complete report / macro SetStep set t = {s} times {lb} set t = {t} times {sz}`The variable t now contains the step size / macro step`Define macro to increment waterplane page set x = {x} plus {t} height(1) {x} `Sets the waterline relative to the critical point solve trim `Find equilibrium holding heel constant \---Report Step {stepnum}---\ set stepnum = {stepnum} plus 1 .status display status /sync if {displ} < 2 then \More steps than needed. | print prev | report off | exit /clear / ` End of Macro Definition `======================================= solve weight, lcg`Solve using drafts `solve`Solve using weight .mk_block \---Report Initial Condition---\ .status .mk_point status crtpt .SetStep .step ({ns}) `Number of steps in parentheses if {displ} > 2 then \Docking not complete |;; \Increase number of steps(ns) or step size(sz) print preview report off ``` Add a free link to your site