From 1415cf2c816b294d06fdc8bd8b29ca6c012be03d Mon Sep 17 00:00:00 2001 From: Laurent Mutricy Date: Thu, 15 Oct 2026 15:47:13 +0200 Subject: [PATCH 1/3] add R3 sudlink and stuless lineProps, resolves #69 --- moorpy/library/MoorProps_newCosts.yaml | 32 ++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-) diff --git a/moorpy/library/MoorProps_newCosts.yaml b/moorpy/library/MoorProps_newCosts.yaml index 0db6c11..980b153 100644 --- a/moorpy/library/MoorProps_newCosts.yaml +++ b/moorpy/library/MoorProps_newCosts.yaml @@ -87,10 +87,34 @@ lineProps: Ca : 1.0 # added mass coefficient based on Bureau Veritas 493-NR_2021-07 Ca_ax : 0.5 # axial added mass coefficient based on Bureau Veritas 493-NR_2021-07 - chainR3 : # R3 grade chain, studless and studlink. Not included in OMAE2025-156384 in interest of brevity - mass_d2 : 21e3 # linear mass density per diameter^2 [kg/m/m^2] - avg R4 studlink and R4 studless - cost_d : -2.34e2 # cost per meter per diameter [2024$/m^2] - cost_d2 : 5.95e4 # cost per meter per diameter^2 [2024$/m^3] + chainR3 : # R3 grade chain, studless + mass_d2 : 20.0e3 # linear mass density per diameter^2 [kg/m/m^2] + EA_d3 : -6.283e07 # stiffness per diameter^3 [N/m^3] + EA_d2 : 84.82e9 # stiffness per diameter^2 [N/m^2] + MBL_d3 : -1.784e09 # minimum breaking load per diameter^3 [N/m^3] + MBL_d2 : 9.812e08 # minimum breaking load per diameter^2 [N/m^2] + MBL_d : 1.033e03 # minimum breaking load per diameter [N/m] + dvol_dnom : 1.80 # volume-equivalent diameter per nominal diameter [-] (assumes 7,850 kg/m^3 material density) + cost_d : -2.18e02 # cost per meter per diameter [2024$/m^2] deemed 30% cheaper than R4 + cost_d2 : 5.99e04 # cost per meter per diameter^2 [2024$/m^3] deemed 30% cheaper than R4 + Cd : 1.333 # drag coefficient based on DNV-OS-E301 adjusted for use with volumetric diameter + Cd_ax : 0.639 # axial drag coefficient based on DNV-OS-E301 adjusted for use with volumetric diameter + Ca : 1.0 # added mass coefficient based on Bureau Veritas 493-NR_2021-07 + Ca_ax : 0.5 # axial added mass coefficient based on Bureau Veritas 493-NR_2021-07 + + chainR3_studlink : # R3 grade chain, studllink. + mass_d2 : 21.9e3 # linear mass density per diameter^2 [kg/m/m^2] (same density as R4) + EA_d2 : 88.0e9 # stiffness per diameter^2 [N/m^2] + MBL_d3 : -1.784e09 # minimum breaking load per diameter^3 [N/m^3] + MBL_d2 : 9.812e08 # minimum breaking load per diameter^2 [N/m^2] + MBL_d : 1.985e03 # minimum breaking load per diameter [N/m] + dvol_dnom : 1.89 # volume-equivalent diameter per nominal diameter [-] (assumes 7,850 kg/m^3 material density) + cost_d : -2.18e02 # cost per meter per diameter [2024$/m^2] deemed 30% cheaper than R4 + cost_d2 : 5.99e04 # cost per meter per diameter^2 [2024$/m^3] deemed 30% cheaper than R4 + Cd : 1.376 # drag coefficient based on DNV-OS-E301 adjusted for use with volumetric diameter + Cd_ax : 0.741 # axial drag coefficient based on DNV-OS-E301 adjusted for use with volumetric diameter + Ca : 1.0 # added mass coefficient based on Bureau Veritas 493-NR_2021-07 + Ca_ax : 0.5 # axial added mass coefficient based on Bureau Veritas 493-NR_2021-07 wire : # wire rope mass_d2 : 5293 # linear mass density per diameter^2 [kg/m/m^2] From d21d65f8717247a92a04172d1c5eabf14c79deb2 Mon Sep 17 00:00:00 2001 From: Laurent Mutricy Date: Thu, 15 Oct 2026 15:52:24 +0200 Subject: [PATCH 2/3] fix chain cost --- moorpy/library/MoorProps_newCosts.yaml | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/moorpy/library/MoorProps_newCosts.yaml b/moorpy/library/MoorProps_newCosts.yaml index 980b153..b3e2e21 100644 --- a/moorpy/library/MoorProps_newCosts.yaml +++ b/moorpy/library/MoorProps_newCosts.yaml @@ -95,8 +95,8 @@ lineProps: MBL_d2 : 9.812e08 # minimum breaking load per diameter^2 [N/m^2] MBL_d : 1.033e03 # minimum breaking load per diameter [N/m] dvol_dnom : 1.80 # volume-equivalent diameter per nominal diameter [-] (assumes 7,850 kg/m^3 material density) - cost_d : -2.18e02 # cost per meter per diameter [2024$/m^2] deemed 30% cheaper than R4 - cost_d2 : 5.99e04 # cost per meter per diameter^2 [2024$/m^3] deemed 30% cheaper than R4 + cost_d : -2.34e2 # cost per meter per diameter [2024$/m^2] + cost_d2 : 5.95e4 # cost per meter per diameter^2 [2024$/m^3] Cd : 1.333 # drag coefficient based on DNV-OS-E301 adjusted for use with volumetric diameter Cd_ax : 0.639 # axial drag coefficient based on DNV-OS-E301 adjusted for use with volumetric diameter Ca : 1.0 # added mass coefficient based on Bureau Veritas 493-NR_2021-07 @@ -109,8 +109,8 @@ lineProps: MBL_d2 : 9.812e08 # minimum breaking load per diameter^2 [N/m^2] MBL_d : 1.985e03 # minimum breaking load per diameter [N/m] dvol_dnom : 1.89 # volume-equivalent diameter per nominal diameter [-] (assumes 7,850 kg/m^3 material density) - cost_d : -2.18e02 # cost per meter per diameter [2024$/m^2] deemed 30% cheaper than R4 - cost_d2 : 5.99e04 # cost per meter per diameter^2 [2024$/m^3] deemed 30% cheaper than R4 + cost_d : -2.34e2 # cost per meter per diameter [2024$/m^2] + cost_d2 : 5.95e4 # cost per meter per diameter^2 [2024$/m^3] Cd : 1.376 # drag coefficient based on DNV-OS-E301 adjusted for use with volumetric diameter Cd_ax : 0.741 # axial drag coefficient based on DNV-OS-E301 adjusted for use with volumetric diameter Ca : 1.0 # added mass coefficient based on Bureau Veritas 493-NR_2021-07 From 605d20076f6d068a9c7c24bd3bc9b2be1e58c5df Mon Sep 17 00:00:00 2001 From: mutricyl <118692416+mutricyl@users.noreply.github.com> Date: Fri, 16 Oct 2026 09:58:19 +0200 Subject: [PATCH 3/3] add notes for R3 chains properties --- moorpy/library/MoorProps_newCosts.yaml | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/moorpy/library/MoorProps_newCosts.yaml b/moorpy/library/MoorProps_newCosts.yaml index b3e2e21..31ffc4b 100644 --- a/moorpy/library/MoorProps_newCosts.yaml +++ b/moorpy/library/MoorProps_newCosts.yaml @@ -48,10 +48,11 @@ # Chain Notes # - The MBLs between studless and studlink chains are the same, for every grade # - The masses between different grades of chain are the same (for now...different grades might correspond to different material densities) -# - If the user needs a different grade of chain, they will have to add another section and include those properties here. This default file only considers R4 chain +# - If the user needs a different grade of chain, they will have to add another section and include those properties here. This file only considers R3 and R4 chain # - This default yaml uses R4 studless chain as the default style of chain # - The chain MBL uses a cubic function, so be aware if you are researching theoretical chains with diameters greater than about 360mm, as the MBL will then decrease -# - Chain EA values not provided in manufacturer catalogs, so the below coefficients are taken from DNV-OS-E301 2013 +# - Chain EA values not provided in manufacturer catalogs, so the below coefficients are taken from DNV-OS-E301 2013 section 2.1.8 +# - R3 Chain MBL is derived from Anchor Marine Houston catalogue pages 52&53 (https://anchormarinehouston.com/wp-content/uploads/2023/08/Anchor-Marine-Catalog.pdf) # Note: costs combine all provided coefficients. If a coefficient is not provided it is assumed zero. All provided values will be used according to: # cost per meter = 'cost_0' + 'cost_d' * d + 'cost_d2' * d**2 + 'cost_d3' * d**3 + 'cost_mass' * mass per meter + 'cost_EA' * EA + 'cost_MBL' * MBL @@ -164,4 +165,4 @@ lineProps: Ca : 1.1 # added mass coefficient based on Bureau Veritas 493-NR_2021-07 Ca_ax : 0.15 # axial added mass coefficient based on Bureau Veritas 493-NR_2021-07 cost_d : -2.27e3 # cost per meter per diameter [2024$/m^2] - cost_d2 : 1.10e5 # cost per meter per diameter^2 [2024$/m^3] \ No newline at end of file + cost_d2 : 1.10e5 # cost per meter per diameter^2 [2024$/m^3]