the multicomponent particle temperature is shown. the droplet temp is 297, and surrounding temperature is 298. then how particles temperature is falling to 75 K?
Still willing to know what do you expect? The gas is cooled as we are evaporating, now the cooled gas is in the contact with the non volatile part of the particle, heat exchange-> droplet is cooled. Also check the change of heat sing in the dpm summary: A positive Change of Heat denotes that heat is expelled from the continuous phase and absorbed by the particle, while a negative Change of Heat denotes heat is released by the particle to the continuous phase.
Double check if the sum of the DPM Enthalpy Source is in the same magnitude range as the one from the DPM summary (with negative sign)
Are you injecting enough particles? What about your computational grid? Which sub-models are activated? What is the definition of your particles in terms of composition?
I am injecting single particle(0.2 NaCl and 0.8 water) water is set to evaporate and NaCl not. Energy is ON, Turbulance model is Realizable K- epsilon, Species transport ON, DPM is ON and set to 10 interactions with continuous phase after established continuous flow field.
I did face mesing for an axisymmetric domain. the domain size is 0.6 m in length and 0.125m in height. i meshed with 1mm mesh size.
Please can you post images of the fluid temperature. How big is the droplet?
as well as the multicomponent droplet properties.
(Nacl (fluid droplet-particle)
(chemical-formula . Nacl<l>)
(density (constant . 2160))
(specific-heat (constant . 88))
(thermal-conductivity (constant . 0.574))
(viscosity (constant . 0.001))
(dpm-surften (constant . 0.063))
(molecular-weight (constant . 58.44))
(reference-temperature (constant . 298.15))
(volatile-fraction (constant . 0.01))
(binary-diffusivity (constant . 1.57e-9))
(species (names h2o<l> Nacl<l>))
the droplet diameter is 1.8mm
Not enough: screenshot from the panel of multicomponent particles to check what is set there. Is the case two-way coupled? If node based averaging is enabled please disable it. Just use Linearize Source Terms instead.
when i keep higher temperature difference between the droplet and ambient the solution looks good but having low temperature difference causes the drop in temperature
The case is two way coupled
AFTER LINEARIZING SOURCE TERM SAME RESULTS OBTAINED
hi I tried with the multicomponent droplet evaporation case file given in the customer portal, i changed the fluid temperature 301 and droplet temperature 300. other parameters are same as in the case file. in this case also droplet temperature is reducing, i attached the plot for the simulation
Sir, I am expecting your kind help for finishing the work, please help me.
Which case on the customer portal? I will need to check it.
Let me describe what can be realistic: droplet will heated till it reaches the vaporization temperature stars the law 2 then law 3. The latent heat is provided from continuous phase, temperature is reduced of the gas phase which might affect the droplet too if caught in re-circulation region or has a large stokes numbers. Same might happen with MM particle. But the change should not be dramatic for that reason: if you have seeing the behavior on a case from the customer portal please share with us the case / solution number.
Worth testing though with update source terms every iteration / transient particle tracking.
I wil provide the link of that case file here sir
the solution number is 2046025
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