All Questions
Tagged with thermodynamics fluid-dynamics
609 questions
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Why are turbines built differently when a change of entropy or temperature is involved?
We are talking about turbines for extraction of energy from a fluid.
Consider a typical wind turbine, or a francis turbin for water - we have one hub with on set of vanes that are driven by the ...
- 2,142
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Why is compressible flow near the choke point so efficient?
Imagine a steady state, one-dimensional, compressible flow in a horizontal pipe of constant cross sectional area. This flow can be isothermal, adiabatic (Fanno), or diabatic (Rayleigh). As an example,...
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Why do steam bubbles increase in size as they rise?
In the following video (a customer's review of a glass kettle), we can observe water boiling: http://youtu.be/jByY5I7Xk7w?t=2m55s
As the kettle starts to boil at around 2:55, we can see large steam ...
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How can I calculate the amount of bubbles needed to lift a submerged body?
Our teacher had us come up with our own thermodynamics experiments, so I put a glass of water inside a vacuum-capsule. Inside the glass of water I have placed a non-floating object, a small plastic ...
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What's the efficency of a steam jet pump?
Jet pumps or venturi pumps are often stated as having a "terribly low" efficiency, steam jet pumps specifically are usually describes as "only justifiable when there's an abundant steam supply anyway" ...
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Do the properties of two streams flowing into an engine add together when they mix?
Let's say I have two stream supplys that have separate mass flow rates, enthalpies, and velocities that flow into an engine. Upstream of the engine's inlet, the two streams mix to form one stream that ...
- 1,158
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How to calculate heat exchange/deltaT in a moving volume of fluid?
I am building a preheater for a maple syrup evaporator and am going to use the steam generated by the heating process to pre-heat the incoming sap from, say 5 degrees C to (hopefully) something on the ...
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the form of a kettle
What is the best form for a kettle, that is, to have the water boil the fastest? I am particularly interested in the following case: for one given kettle (whose volume is constant) containing ...
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What cools a drink?
When you stick ice in a drink, AFAICT (the last physics I took was in high school) two things cool the drink:The ice, being cooler than the drink, gets heat transferred to it from the drink (Newton's ...
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