Page 74 - DJJ20063- Thermodynamics 1
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DJJ20063- Thermodynamics 1



                      The reversible constant volume process is shown on a P-V diagram in Fig. 2.5-1.


                                    P

                                   P2               2




                                   P1               1

                                                                  V
                                               V1 = V2
                              Figure 2.5 -1   P-V diagram for reversible constant volume process





                      Example 2.14

                                                                              3
                                                                                                    o
                        3.4 kg of gas is heated at a constant volume of 0.92 m  and temperature 17  C until

                                                    o
                        the temperature rose to 147  C.  If  the gas is assumed to be a perfect gas, determine:

                           a)  the heat flow during the process

                           b)  the beginning pressure of gas

                           c)  the final pressure of gas

                        Given

                        Cv = 0.72 kJ/kg K

                        R = 0.287 kJ/kg K



                      Solution to Example 2.14


                      From the question

                      m = 3.4 kg
                                      3
                      V1 = V2 = 0.92 m
                      T1 = 17 + 273 K = 290 K

                      T2 = 147 + 273 K = 420 K

                      Cv = 0.72 kJ/kg K

                      R = 0.287 kJ/kg K



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