I humbly ask: When steam flows in reverse to heat the fluid, are there still bubbles present?
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I humbly ask: When steam flows in reverse to heat the fluid, are there still bubbles present? Saturated water vapor: 4 kg of pressure, direct heating in counterflow. Will there still be bubbles in the water? ? ? What theories can be used as a reference for the direct mixing process of water vapor and water? Thank you so much, guys! !
If non-condensable gases are not taken into account, there are no bubbles after mixing.
If there is enough water, there should be no bubbles.
Is a liquid-to-gas mass ratio of 7.6 considered large enough?
It is difficult to determine the absence of bubbles with only one gas-liquid ratio. .
Right, bubbles are dissolved in the water beforehand; they’re not brought in by steam
First of all, there will be no bubbles (unless there are already non-condensable gases present). This is a process of heat and mass transfer between vapor and liquid; calculations are carried out based on the laws of energy conservation and mass conservation, and the final state is determined by the pressure and temperature after mixing.
This seems to be related to the contact time between vapor and liquid. The difference between water and water vapor lies in their molecular kinetic energies; water molecules in water vapor possess higher kinetic energies and are in a state of random motion. From a molecular perspective, the basis for heat transfer from water to vapor is the transfer of momentum through molecular collisions. During the water-vapor contact process, when all the water vapor molecules become low-energy molecules, the (water vapor) bubbles disappear (of course, assuming no non-condensable gases are present)
In factories, heating is generally achieved by supplying saturated steam directly to the header tanks; water hammer phenomena often occur in the pipelines, so bubbles are still present in practice.
There should be bubbles! It depends on the ratio of water vapor, but the pressure of the gas coming in also needs to be taken into account! But there’s enough water! It can’t be guaranteed that no bubbles will get through! I think that’s the case!
Could you explain what \"water hammer\" is? Learn* it a bit. Thank you
In pressurized pipelines, sudden changes in water flow velocity due to external factors such as the sudden closure of a valve or the sudden shutdown of a water pump can cause alternating increases and decreases in pressure. This hydraulic phenomenon is known as water hammer. Due to water hammer, the pressure in the pipes increases sharply, reaching several times or even a dozen times the normal pressure; this poses serious risks as it can cause the pipes to burst, affecting production and daily life.
I also searched for relevant information. So, may I ask: the severe vibrations that occur in my case due to heat exchange between steam flowing in reverse direction and water coming into direct contact with each other – does this belong to the phenomenon of \"water hammer\", \"water impact\", or \"steam hammer\"? Thank you.
Water hammer phenomenon. Whether there is steam present after prolonged mixing or not, obvious steam bubbles will definitely be present during the mixing process. This is because not only does steam condense into liquid, but water also turns into steam due to changes in pressure. It’s easy to understand – how could such a large volume of steam simply turn into liquid in an instant, with its volume decreasing by a factor of a thousand? ； Even with intense stirring and mixing using a injector, bubbles can still exist in the tail pipe. The original question from the poster is actually a simple energy balance calculation. This post was last edited by wycasia on 2009-3-11 16:21]
There are bubbles. If not much steam is added and there is enough time for it to come into contact with the water, then only the non-condensable gases in the water will precipitate, resulting in mild bubbling ； If the contact time between steam and water is insufficient, more intense bubbling may occur (the degree depending on the amount of steam added).
I think there are bubbles, but they are not caused by steam; rather, they arise from the agitation of the water as steam comes into contact with it and cools down, condensing, as well as from the release of gases dissolved in the water due to localized heating. When steam is mixed with water more evenly, the bubbles are smaller, and most of them dissolve back into the water ； Conversely, bubbles and vapors will be generated, causing significant vibration.