Ankit Saxena

MIXING OF HOT AND COLD WATER CFD

•  CAD :
  The geometry is a simple 2 inlet pipe with a mixing junction and an outlet. Cold Water enters from one end and combines with hot water coming from the second end at the junction both inlets are velocity inlets and the outlet is pressure outlet set to zero. (NOT A WALL)
  
•  MESHING :
  Learned the importance of slicing up the geometry

Unsliced Geometry

Sliced up geometry

•  Running the solution :
  1) check the mesh
  2) Enable the energy equation and k-epsilon models
  3) set the boundary conditions for the inlet and the outlet and also specify their      temperatures
  4)Intialise the solution and run the calclations
• Results:
  Cold velocity inlet= 0.05m/s hot velocity inlet= 0.05m/s
  Cold water temperature = 300K
  Hot water temperature = 400K

• 400 gsm Carbon fiber
  
  
• 100 gsm e glass fiber
  
  
• 200 gsm e glass fiber
  
  
• DIAB divinycell
  
  
• Araldite AY 105 epoxy  with  HY 991 hardener (10:1)
• Felt (breather cloth) : It is used for absorbing the excess epoxy that is pulled up by the vacuum pump.
• Teflon coated glass fiber (Separator): It is used for separating the breather cloth from the epoxy covered CF/GF layers and prevents them from sticking to each other.
• Vacuum bag
  
  
• Double sided butyl tape (Tacky tape) : It is used for sealing the vacuum bag.
  
  
  

• Clean the moulding surface and apply 2 coats of mould releasing agent.
• Make the vacuum bag and seal it from all sides but one which will be used to insert the laminates.
• Cut the required pieces of breather and separator.
• Measure the required amount of epoxy and its hardener.
• Begin layup by applying epoxy on the moulding surface. (The amount of epoxy on the first layer must be more than the others so that it can be sucked up by the vacuum).
• Place the required layers one by one covering them with just enough epoxy so as to wet the layers completely.
• Place the separator followed by the breather after all the layers have been layed up
• Place the templates inside the vacuum bag and seal the bag.
• Start the vacuum pump to begin the process.
• Check for any leaks and make sure that a sufficient amount of vacuum is established.