This file can be used to specify the location of emitter points. It is most useful when the user has specific (and many) emit points to use for particle traces. Rather than type them all in one at a time as a cursor emitter, this file can be used.
Note the following:
1. The first two lines need to be exactly as shown.
Version 1.0 EnSight Particle Emitter File
2. #'s as the first character on a line, are comment lines. Comment lines can be used anywhere in the file after the first two mandatory lines.
3. Time lines contain the
emitter release time (floating point time value, NOT the integer time step).
4. Emit lines contain the
coordinates of an emitter. The emitter will be associated with the previously specified Time .
There is one special case that may be useful to know. An option within
EnSight is to have traces emitted at the "current time". You can use that option with an
emitter file if your number of emitters and their locations do not change over time. Just omit
the Time line in this file (and remember to set the
emit at current time toggle in EnSight).
If you use an emitter and choose the pathline option, then each emitter will emit a particle trace at the indicated time.
However, if you use an emitter file and choose the streamline option, then streamlines will be emitted at all of the Emit locations at once. Some might expect this to operate as if streamlines are calculated at the 'current time' and as you move through time, previous streamlines are removed and the new streamlines are recalculated at the current timestep using the new emitter locations. This is not the way this works when you use an emitter file with changing emitter locations. Each streamline will emit at the time indicated in its Time keyword using the flowfield corresponding to that Time keyword. You will end up with groups of streamlines emitted at a common time and calculated at that common time all showing up at once and all using a relative time value all starting from 0.0. It can be quite confusing if you expect an 'emit at current time' behavior.
Sample File:
Version 1.0 EnSight Particle Emitter File # Time 0.249063 Emit 0.0669737 0.0134195 -0.013926 Emit 0.0669737 0.0131277 -0.0141079 Emit 0.0669737 0.0128642 -0.0143178 Emit 0.0669737 0.0155969 -0.0113572 Emit 0.0669737 0.0150344 -0.0122012 Emit 0.0669737 0.0146967 -0.0123587 # Time 0.249113 Emit 0.0669737 0.0137097 -0.0136404 Emit 0.0669737 0.0134218 -0.0138284 Emit 0.0669737 0.0131628 -0.0140438 Emit 0.0669737 0.01585 -0.0110264 Emit 0.0669737 0.0152879 -0.011882 Emit 0.0669737 0.0149536 -0.0120466 # Time 0.249163 Emit 0.0669737 0.0139938 -0.0133488 Emit 0.0669737 0.01371 -0.0135428 Emit 0.0669737 0.0134555 -0.0137636 Emit 0.0669737 0.0160612 -0.0106906 Emit 0.0669737 0.0155347 -0.0115575 Emit 0.0669737 0.0152039 -0.0117291 # Time 0.249213 Emit 0.0669737 0.0142718 -0.0130512 Emit 0.0669737 0.013992 -0.01511 Emit 0.0669737 0.0137423 -0.0134773 Emit 0.0669737 0.0162827 -0.0103501 Emit 0.0669737 0.0157745 -0.0112279 Emit 0.0669737 0.0154475 -0.0114064 # Time 0.249263 Emit 0.0669737 0.0145433 -0.0127479 Emit 0.0669737 0.0142679 -0.0129536 Emit 0.0669737 0.014023 -0.013185 Emit 0.0669737 0.0164969 -0.0100051 Emit 0.0669737 0.0160074 -0.0108933 Emit 0.0669737 0.0156842 -0.0110787