When can we use the absorption refrigeration system How are

When can we use the absorption refrigeration system? How are the (i) ammonia and (II) water used as in the absorption refrigeration system converted in the class? Why is the Carnot cycle not a realize model for stream power plant? Mention only two reactions. Define the following (i) Cutoff radio r_e and (ii) compression ratio r. Mention only two comparisons between SI (gasoline engine and CI (Diesel) engine. For the stream power plant shown below, determine the fractions y and z. Take h_2 = 192.12, h_3 = 561.47, h_4 = 574.56, h_5 = 734.16, h_6 = h_7 = 721.00, h_9 = 2754.12, h_10 = 2577.7 kJ/kg.

Solution

(a)An absorption refrigeration system is used instead of compressor used in case of vapor absorption refrigeration system. During the process of suction and compression which are carried out by two equipment, generator and absorber. The absorber and generator replaces the compressor in vapor absorption cycle . Here the absorbent permits the flow of refrigerant from the absorber to the generator by absorbing it.

(i) AMMONIA is used as a weak solution of the refrigerant (ii) water is used as absorbent.

(b) For a steam power plant Carnot cycle is not realistic model due to (I) the turbine of steam power plant will need to handle steam with high level of moisture content due to which erosion takes place (II) it is impossible to design a compressor with two phases.

(C) (i) CUTOFF RATIO is defined as the ratio of volume after fuel combustion to the volume before fuel combustion.

(ii) COMPRESSION RATIO is the ratio of maximum volume to minimum volume in the cylinder of an IC engine.

(d) (i) SI engines have spark plugs while CI engines do not have spark plug.

(ii) SI engine has low thermal efficiency while CI has high thermal efficiency.