Page 41 - Fundamentals of The Finite Element Method for Heat and Fluid Flow
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SOME BASIC DISCRETE SYSTEMS



















                                          Figure 2.11 Pipe network for central heating         33



                                                Cooling fluid out





                                     Hot fluid                               Cold fluid






                                                                          Cooling fluid in
                                                  A                     A
                                                            L


                                           Figure 2.12 Counterflow heat exchanger


                        metal to the mould via radiation and conduction. Then heat is conducted through the mould
                        and convected to the atmosphere. Stating all assumptions, derive a system of equations to
                        carry out a transient analysis.


                        Exercise 2.5.6 Consider a 0.6-m high and 2-m wide double-glazed window consisting of
                                                             ◦
                        two 4 mm thick layers of glass (k = 0.80 W/m C) separated by an 8-mm wide stagnant air
                        space (k = 0.025 W/m C). Determine the steady state heat transfer through the window and
                                          ◦
                        the temperature of the inner surface for a day when the outside air temperature is −15 C
                                                                                               ◦
                                                   ◦
                        and the room temperature is 20 C. The heat transfer coefficient on the inner and outer
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