The Gibb Seawater Equation of State (GSW) is what oceanographers use to calculate fundamental properties of seawater. Currently there are a couple implementation of the C version of the library in Julia but none of them are working with macOS. If someone can help me develop a version fo macOS, it would be very appreciate. Thanks!
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im working with Helmholtz EOS, I have the IAPWS95-2018 (just water) and the GERG2008 (natural gas) implemented. (working on a PT solver too). i can help you.
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looking at this paper. a lot of implementations use the IAPWS95 + a correction term. so implementing the correction terms is whats missing
Sounds like you are doing a Julia native implementation?
Always wanted to see an implementation of GERG! Any chance you could share?
of helmholtz EOS, mainly. the idea i have is an agnostic EOS system. the derivatives are calculated via ForwardDiff and i’m working on a PT solver (multicomponent, i haven’t did anything with monocomponent, like IAPWS95), there are good tools to work on that
of course, check this:
https://github.com/longemen3000/LavoisierCore.jl/blob/master/src/gerg2008.jl
my idea is that the EOS is a struct, and you pass the struct to calculate a property: for example:
mymodel = GERG2008(:CH4,:H2O,:CO2)
pressure(mymodel,2u"kg/m^3",300u"K",[0.1,0.2,0.7])
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Wow! I admire your tenacity thank you. I will have to fork this and play with it a bit.
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for all 21 compunds, it takes around 121 μs per helmholtz evaluation, a binary one takes around 4μs (IAPWS95 takes around the same as a binary GERG). if you need properties, you just differenciate the helmholtz function with ForwardDiff (zygote is too slow in this case)
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Could you try this ?
This is just a wrapper and I don’t have an OSX environment, but it seem to be successful to build on the travis (osx) now.
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Thanks @kouketsu!!! I just installed your GSW.jl package and it works! The installation went without a hitch on a new macOS machine but on my old machine I had to manually remove a previous non-working installation to make it precompile correctly. Thanks again!
Longeman I really love the scope your package is aiming for but I tried to use it with a GERG mixture of 2 components and got an array out of bounds error.
how you are calling it?
when you call model = GERG2008() , you call it with all 21 compounds in the order of the kunst paper. if you want a custom order, you can call GERG2008(compounds...), where the list of accepted compounds are:
symvalues = [:CH4, :N2, :CO2, :C2, :C3, :nC4, :iC4, :nC5, :iC5, :C6, :C7, :C8, :C9, :C10,
:H2, :O2, :CO, :H2O, :H2S, :He, :Ar]
for example: a water-H2S mixture can be called via:
model = GERG2008(:H2O,:H2S)
core_pressure(model,0.01,373,[0.9,0.1])
I don’t have the code right now, I think I ran it like this,
m = GERG2008(:CH4, :C3)
density(m,2u"kg/m^3",300u"K",[0.1,0.2])
and it gave me an array out of bounds error, something like “tried to access index 3 of a 2 index array”
Maybe I cloned master at an inopportune time though
I have density? I dont remember coding that lol
Give me a moment and i will give you proper molar_density and mass_density
Think I meant pressure sorry! Density would be awesome though!
You can check how many compounds yor model have with length(model)
let me try again I cannot find where I cloned it to!
julia> pressure(m,2u"kg/m^3",300u"K",[0.1,0.2])
ERROR: BoundsError: attempt to access 2-element Array{Float64,1} at index [6]
Stacktrace:
[1] getindex at ./array.jl:731 [inlined]
[2] _fr2(::GERG2008, ::ForwardDiff.Dual{ForwardDiff.Tag{getfield(LavoisierCore, Symbol("##37#38")){GERG2008,Array{Float64,1}},Float64},Float64,2}, ::ForwardDiff.Dual{ForwardDiff.Tag{getfield(LavoisierCore, Symbol("##37#38")){GERG2008,Array{Float64,1}},Float64},Float64,2}, ::Array{Float64,1}) at /home/caseykneale/try/LavoisierCore.jl/src/gerg2008.jl:626
[3] core_helmholtz(::GERG2008, ::ForwardDiff.Dual{ForwardDiff.Tag{getfield(LavoisierCore, Symbol("##37#38")){GERG2008,Array{Float64,1}},Float64},Float64,2}, ::ForwardDiff.Dual{ForwardDiff.Tag{getfield(LavoisierCore, Symbol("##37#38")){GERG2008,Array{Float64,1}},Float64},Float64,2}, ::Array{Float64,1}) at /home/caseykneale/try/LavoisierCore.jl/src/gerg2008.jl:671
[4] vector_mode_gradient(::getfield(LavoisierCore, Symbol("##37#38")){GERG2008,Array{Float64,1}}, ::Array{Float64,1}, ::ForwardDiff.GradientConfig{ForwardDiff.Tag{getfield(LavoisierCore, Symbol("##37#38")){GERG2008,Array{Float64,1}},Float64},Float64,2,Array{ForwardDiff.Dual{ForwardDiff.Tag{getfield(LavoisierCore, Symbol("##37#38")){GERG2008,Array{Float64,1}},Float64},Float64,2},1}}) at /home/caseykneale/try/LavoisierCore.jl/src/core.jl:74
[5] gradient(::Function, ::Array{Float64,1}, ::ForwardDiff.GradientConfig{ForwardDiff.Tag{getfield(LavoisierCore, Symbol("##37#38")){GERG2008,Array{Float64,1}},Float64},Float64,2,Array{ForwardDiff.Dual{ForwardDiff.Tag{getfield(LavoisierCore, Symbol("##37#38")){GERG2008,Array{Float64,1}},Float64},Float64,2},1}}, ::Val{true}) at /home/caseykneale/.julia/packages/ForwardDiff/N0wMF/src/gradient.jl:17
[6] gradient(::Function, ::Array{Float64,1}, ::ForwardDiff.GradientConfig{ForwardDiff.Tag{getfield(LavoisierCore, Symbol("##37#38")){GERG2008,Array{Float64,1}},Float64},Float64,2,Array{ForwardDiff.Dual{ForwardDiff.Tag{getfield(LavoisierCore, Symbol("##37#38")){GERG2008,Array{Float64,1}},Float64},Float64,2},1}}) at /home/caseykneale/.julia/packages/ForwardDiff/N0wMF/src/gradient.jl:15 (repeats 2 times)
[7] core_grad_vt at /home/caseykneale/try/LavoisierCore.jl/src/core.jl:75 [inlined]
[8] core_pressure(::GERG2008, ::Float64, ::Int64, ::Array{Float64,1}) at /home/caseykneale/try/LavoisierCore.jl/src/core.jl:161
[9] pressure(::GERG2008, ::Quantity{Int64,𝐌*𝐋^-3,Unitful.FreeUnits{(kg, m^-3),𝐌*𝐋^-3,nothing}}, ::Quantity{Int64,𝚯,Unitful.FreeUnits{(K,),𝚯,nothing}}, ::Array{Float64,1}) at /home/caseykneale/try/LavoisierCore.jl/src/core.jl:170
[10] top-level scope at none:0
julia> length(m)
2