Effect of Helium-Argon Mixtures on the Heat Transfer and Fluid Flow in Gas Tungsten Arc Welding

A transient finite element model has been developed to study the heat transfer and fluid flow during spot Gas Tungsten Arc Welding （GTAW） on stainless steel. Temperature field, fluid velocity and electromagnetic fields are computed inside the cathode, arc-plasma and anode using a unified MHD formulation. The developed model is then used to study the influence of different helium-argon gas mixtures on both the energy transferred to the workpiece and the time evolution of the weld pool dimensions. It is found that the addition of helium to argon increases the heat flux density on the weld axis by a factor that can reach 6.5. This induces an increase in the weld pool depth by a factor of 3. It is also found that the addition of only 10% of argon to helium decreases considerably the weld pool depth, which is due to the electrical conductivity of the mixture that increases significantly when argon is added to helium.

Common Sense Empirical Climate Science:No Carbon Climate Crisis at Current Trace Levels

Climate science deals with the harsh reality of 174,000 terawatt of solar energy striking Earth’s surface&air,minus 29 percent albedo.The exposure is sustained by the planet cooling itself by means of EM radiation emitted to outer space of a like amount of energy in the infrared range.The balance may not be perfect at all times,but miraculously we are still around&attempting to comprehend the physical processes involved in keeping the planet’s surface suitable to sustain biological life&human civilization.While ground temperature is maintained at a pleasant avg 288 kelvin=15℃by the atmospheric greenhouse effect,a surprising 255 kelvin satisfies the demand for radiative cooling.This just happens to be standard air temperature at 5,000 m altitude.Official climate science largely is concerned with models&has assigned a major role to carbon molecules in air.As these exist currently only at mere trace levels,they are widely considered to be irrelevant for climate in view of the Mass-Action Law that implies that trace components can have only trace effects.Denying this simple fact,familiar to meteorologists,unfortunately has led to much of the civilized public being misled by climate scientists.One of the themes among their rhetoric is calling for renewable energy sources,when in reality unlimited amounts of hydrogen&hydrocarbons are dissolved in the Earth’s mantle,going back to the primitive solar nebula that gave rise to our solar system,&available for human consumption through fracking.Here in this philosophical essay,we are offering simple empirical proofs,examples from everday life,as opposed to the largely theoretical modeling work of climate science,for the fact that atmospheric carbon molecules can have only trace effects on radiative planetary cooling,proofs that are easy to verify.We dispute unrealistic estimates of important effects on climate from carbon dioxide trace gas via an atmospheric feedback mechanism proposed by some climate scientists.The essay demonstrates that atmospheric carbon molecules are irrelevant for climate at this epoch.Humanity is not facing a carbon climate crisis,currently.