OpenFOAM version: 9 Case: clamp_09 Points of note: new coarser mesh, adjust time step implemented, 60 minute simulation. NEW MESHES There is a need for more speed in this simulation. It is currently moving at about 0.1 seconds per second. So a 3 day simulation would take 30 days. To achieve this increase in speed,…
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Cover image: a sugar beet clamp captured with a drone mounted thermal camera. Skip to Coding convective heat transfer coefficient as a scalar field. BACKGROUND Convective heat transfer is the process by which heat is transfer from one region to another through the movement of a fluid. It results when there is a temperature difference…
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THIS POST IS AN UPDATE ON A PREVIOUS POST IN WHICH THE WRONG KINEMATIC VISCOSITY WAS APPLIED IN THE SIMULATION. In 2003, Lope G. Tabil and three co-authors decided that they would make my 2021 life much much easier by publishing the paper Airflow Resistance of Sugarbeet. This paper reports some very useful values for…
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UNDER CONSTRUCTION 2022-03-03: require experimental data for the permeability of the cover material TopTex. OpenFOAM version: 9 CASE: clamp_06, case_06_empty_clamp Solver: clampPimpleFoam-2 This post builds on two previous posts in which two heat equations were added to the pimpleFoam solver: one for the fluid phase, and one for the solid phase. That said, this post…
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Case: clamp_05 Solver: clampPimpleFoam-1 -> clampPimpleFoam-2 This post is the second of two that are a record of how to modify the pimpleFoam solver of OpenFOAM to include heat transfer when there is: a porous region, two phases in this porous region (gas and solid), and a heat source within the solid phase. In the…
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Case: clamp_04 Solver: pimpleFoam -> clampPimpleFoam This post is the first of two that a record of how to modify the pimpleFoam solver of OpenFOAM to include heat transfer when there is: a porous region, two phases (gas and solid = porous region), and a heat source within the solid region. In this post, a…
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A long time ago (2021-02-17), I wrote that I had a feeling there was something wrong with my CFD model of a sugar beet clamp – the rates of air flow seemed a bit low when compared to a few roughly similar cases. It turns out, there was something wrong with it. The viscosity of…
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It’s a very idealised version of a clamp, but it feels pretty OK. The clamp is 8m wide, 2.4m high, and the cross section is 3m broad. The ventilation pipe is 20cm in diameter, and 5.5m long, from x = 0. There are 12 holes in the pipe, each 6cm in diameter and centered at…
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To verify my CFD model of a sugar beet clamp, measurements of air speed inside of the clamp are desired. It’s something that I have not been able to do with a simple, post-clamp-construction method. In 2021, it is time to test a more embedded, set-up-at-harvest method. To this end, I’ve turned to do-it-yourself electronics.…
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!!!!! THE VALUE USED FOR KINEMATIC VISCOSITY IN THE SIMULATION THAT IS DESCRIBED IN THIS POST WAS INCORRECT. THE DARCY-FORCHHEIMER COEFFICIENTS, HOWEVER, DO SEEM TO BE CORRECT. FOR AN UPDATED ON THE RESULTS IS AVAILABLE !!!!! In 2003, Lope G. Tabil and three co-authors decided that they would make my 2021 life much much easier…
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