Dirk, Jan, On 5 July 2015 at 23:56, Dirk Hohndel <[email protected]> wrote:
> On Sat, Jul 04, 2015 at 12:27:23AM +0200, Jan Darowski wrote: > > Hi, > > Here is another pull request. I hope now it's better. Everything was > > reorganized from scratch, the final code is almost the same. > > I like the patches much better. > I agree with Robert that you could have squashed a couple together, but in > the end I felt it was better to just pull what you had. > > I've reattached the patch to use the same VPM configuration parameters used in other programs. This is necessary to match Eric Baker's 'benchmark' dive profile. The patch is the same as before, but hopefully with a better commit message and line wrapping. I assume this was overlooked rather than deliberately omitted before, but do say if there's a reason why it shouldn't be applied now. The second patch adds units to the structure comments (but not in the variable names). I'm confused by the units for surface_tension_gamma and skin_compression_gammaC. According to http://www.deepocean.net/deepocean/index.php?science04.php surface_tension_gamma = 17.9 dyn/cm = 0.179 N/m, but 17.9 dyn/cm = 0.0179 N/m surface_tension_gamma = 257 dyn/cm = 2.57 N/m, but 257 dyn/cm = 0.257 N/m My previous version of the patch gave the unit as mN/cm, but I'm not sure that's right either. As Jan noted before, it isn't the first error on that page. However, the calculated profile matches the benchmark, so something must be right (or unit errors are cancelling each other out). Cheers, Rick
From 9f27b11f4f0d59b2363195f7d5fee75eb928e8da Mon Sep 17 00:00:00 2001 From: Rick Walsh <[email protected]> Date: Tue, 7 Jul 2015 18:52:29 +1000 Subject: [PATCH 1/2] Use common VPM configuration parameters Adopt the same critical radii used by Eric Baker's original VPM Fortran code and V-Planner. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Standard critical volume lambda = 7500 fsw-min (numerous sources). We need to convert it properly. λ = 7500 fsw-min = 7500/33 = 227.2727 ata-min = 227.2727 * 1.01325 bar-min = 230.284 bar-min Signed-off-by: Rick Walsh <[email protected]> --- deco.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/deco.c b/deco.c index f1bc803..1ec4cae 100644 --- a/deco.c +++ b/deco.c @@ -43,7 +43,7 @@ struct vpmb_config { double regeneration_time; //! Time needed for the bubble to regenerate to the start radius. double other_gases_pressure; //! Always present pressure of other gasses in tissues. }; -struct vpmb_config vpmb_config = { 0.6, 0.5, 250.0, 8.2, 0.179, 2.57, 20160, 0.1359888 }; +struct vpmb_config vpmb_config = { 0.8, 0.7, 230.284, 8.2, 0.179, 2.57, 20160, 0.1359888 }; const double buehlmann_N2_a[] = { 1.1696, 1.0, 0.8618, 0.7562, 0.62, 0.5043, 0.441, 0.4, -- 2.4.3
From a79c208b8f17a6ab0b54ca39c9107a9bb389f9a8 Mon Sep 17 00:00:00 2001 From: Rick Walsh <[email protected]> Date: Tue, 7 Jul 2015 20:25:51 +1000 Subject: [PATCH 2/2] Include units in VPM config structure definition Include units in the comments of VPM structure definition. We should confirm the units surface_tension_gamma and skin_compression_gammC. Signed-off-by: Rick Walsh <[email protected]> --- deco.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/deco.c b/deco.c index 1ec4cae..a801221 100644 --- a/deco.c +++ b/deco.c @@ -36,12 +36,12 @@ struct buehlmann_config buehlmann_config = { 1.0, 1.01, 0, 0.75, 0.35, 1.0, fals struct vpmb_config { double crit_radius_N2; //! Critical radius of N2 nucleon (microns). double crit_radius_He; //! Critical radius of He nucleon (microns). - double crit_volume_lambda; //! Constant corresponding to critical gas volume. - double gradient_of_imperm; //! Gradient after which bubbles become impermeable. + double crit_volume_lambda; //! Constant corresponding to critical gas volume (bar-min). + double gradient_of_imperm; //! Gradient after which bubbles become impermeable (bar). double surface_tension_gamma; //! Nucleons surface tension constant. - double skin_compression_gammaC; //! - double regeneration_time; //! Time needed for the bubble to regenerate to the start radius. - double other_gases_pressure; //! Always present pressure of other gasses in tissues. + double skin_compression_gammaC; //! Skin compression gammaC. + double regeneration_time; //! Time needed for the bubble to regenerate to the start radius (min). + double other_gases_pressure; //! Always present pressure of other gasses in tissues (bar). }; struct vpmb_config vpmb_config = { 0.8, 0.7, 230.284, 8.2, 0.179, 2.57, 20160, 0.1359888 }; -- 2.4.3
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