convection

  1. B

    Radiation and Convection problem

    I am trying to figure out what happens when a parcel of air rises in the atmosphere, and obtains potential energy due to its increased elevation loses kinetic energy proportional to the potential energy gained. Then while at TOA cools in accordance with radiation laws, then drops in the...
  2. R

    Heat Transfer

    Hello, all. I'm a newbie in physics and am looking to pursue mechanical engineering as a degree. Thermodynamics is very interesting, but I'm stumped on a question without any way to test it out. This isn't for school, but rather for my own studies. Does the presence of heat in a conductor...
  3. R

    Convection in isolated box (HELP!!!)

    Hi, I do not have much knowledge about this stuff (just basic things), but I need to know something. How do I calculate, how many cooling elements (bags of ice) do I need to maintain the temperature products (0°C-4°C) inside an isolated box for 24 hours? Depends on the cooling elements...
  4. A

    Natural convection: turbulent or laminar?

    Hello everyone, I am modelling an inclined rectangular cavity and got confused with Grashof and Rayleigh number. I've reviewed many research papers - some researchers use Rayleigh, some Grashof number to determine the type of flow. This is probably very simple but I can't find where my...
  5. R

    Conduction or convection

    Hi, I am working in the design of a packaging for a pressure-temperature sensor, the idea is put the sensot in a silicone oil chamber (diameter 18 mm, heigth 3-8 mm), and over the chamber a steel diaphragm (30 um thickness) receiving the pressure and the temperature. As the silicon oil is...
  6. Z

    How to calculate fluid rise rate and Ra during convection due to density difference?

    I would be very grateful for some help with what is probably a simple problem. I'm a bit of a fluid dynamics newbie. I want to consider natural convection due to density differences, not "forced" convection. For example, a liquid that rises because it is less dense than the surrounding solid...
  7. A

    Heat energy transfer

    I am given this problem (assuming its information is accurate). QNS: Heat energy can travel or transfer A. only from a cold body to hot body B. only from hot body to cold body C. from either a hot body to cold body OR cold body to hot body Based on my understanding of this question...
  8. R

    Water natural convection

    Hello, I have an interesting question about water natural convection without an external heat source. Say we have a high tower filled with water. The tower walls don’t allow any heat to escape or enter the system. There is a constant gravitational force present in a system (g-force). At the...
  9. L

    Convection problem

    Imagine a hollow torus-shaped object filled with any homogeneous gas that is free to flow through the entire object. From a top view, one side's surface is an insulator, and the other is a conductor. If a constant heat source is placed some known distance from the object, and the top-view of the...
  10. F

    Radiation and convection help

    hey im getting the answer 319 but the supposed answer is 219.12 please help me out Consider a person standing in a room. The room air temperature is maintained at 22OC at all times. The inner surface of the walls, floors and the ceiling of the room are observed to be at an average temperature...