Patent Publication Number: US-2015059663-A1

Title: Cooling system for machine system

Description:
TECHNICAL FIELD 
     The present disclosure relates generally to a machine system. More specifically, the present disclosure relates to a cooling system for the machine system. 
     BACKGROUND 
     Internal combustion engines are commonly known to generate power required to run a machine. Exhaust gases from an internal combustion engine may have a high temperature. Typically, the exhaust gases are released into the environment, resulting in a significant waste of thermal energy. Therefore, the internal combustion engine may sometimes be provided with an energy recovery system to recover energy of exhaust gases. 
     The energy recovery system is known to recover energy from the exhaust gases and produce an electrical output. The energy recovery system commonly includes a condenser that requires to be cooled, for efficient production of electrical output. 
     A cooling system is installed to cool the condenser and is powered by the electrical output from the energy recovery system. Conventional cooling systems may include a single fan to cool the condenser as well as a multiplicity of heat generating systems, such as an engine radiator, a transmission and a hydraulic system. Since a single fan is used to cool the condenser and the multiplicity of heat generating systems, the fan may be inefficient to cool the condenser. In addition, a large and/or bulky fan may be required to fulfill the cooling demands of the condenser. This large and/or bulky cooling fan may require a high amount of power for operation, which may not be accomplished by the energy recovery system alone. This may result in poor cooling of the condenser. 
     SUMMARY OF THE INVENTION 
     Various aspects of the present disclosure are directed to a machine system to run a machine. The machine system includes an internal combustion engine, a plurality of heat generating systems, an energy recovery system, and a cooling system. The energy recovery system is in communication with the internal combustion engine. The energy recovery system is adapted to extract heat from exhaust gases associated with the internal combustion engine to produce an electrical output. The energy recovery system includes a condenser to condense a working fluid that circulates within the energy recovery system. The cooling system is integrated with the energy recovery system and includes a plurality of fans, a condenser fan, and a control unit. The plurality of fans is powered by the electrical output produced by the energy recovery system. Each of the plurality of fans is structured and arranged to cool one or more of the plurality of heat generating systems. The condenser fan is powered by the electrical output generated by the energy recovery system and is structured and arranged to cool the condenser. The control unit is adapted to selectively control each of the plurality of fans based on load requirements of the corresponding heat generating system. Thereby the control unit is configured to optimize and maximize heat transfer by the condenser fan to the working fluid. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic block diagram of a machine system that illustrates an energy recovery system and associated cooling system, in accordance with the concepts of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIG. 1 , there is shown a machine system  100  to run a machine. The machine may embody vehicles, such as but not limited to, a construction machine, an irrigation machine, a forest machine, a marine machine, and/or a stationary power machine. The machine system  100  includes an internal combustion engine (ICE)  102 , a plurality of heat generating systems  104 , an energy recovery system  106 , and a cooling system  108 . 
     The ICE  102  is a power source of the machine system  100  that generates power required to run the machine. The ICE  102  works in conjunction with the plurality of heat generating systems  104  to run the machine efficiently. The plurality of heat generating systems  104  may include a transmission system, a hydraulic system, an air to air charge cooling (ATAC) system, an engine radiator, and or other systems known in the art. Moreover, the ICE  102  produces exhaust gases during power generation in the machine system  100 . These exhaust gases may be passed through the energy recovery system  106  to recover heat from the exhaust gases. 
     The energy recovery system  106  may operate using the principles of an organic rankine cycle. The energy recovery system  106  is arranged so that it is in fluid communication with the ICE  102 . The energy recovery system  106  is adapted to receive exhaust gases from the ICE  102  and recover heat from the exhaust gases to produce an electrical output. The energy recovery system  106  includes a fluid pump  110 , an evaporator device  112 , a turbine  114 , an electrical generator  116 , and a condenser  118 . The fluid pump  110  is adapted to circulate a working fluid through the evaporator device  112 , the turbine  114 , and the condenser  118  in a closed loop manner. 
     The evaporator device  112  is in fluid communication with the fluid pump  110  and is disposed downstream of the fluid pump  110 . The evaporator device  112  receives the working fluid from the fluid pump  110  and is adapted to heat the received working fluid. In addition, the evaporator device  112  is in fluid communication with the ICE  102  that facilitates the flow of exhaust gases from the ICE  102  to the evaporator device  112 . Thereby, the energy recovery system  106  is in fluid communication with the ICE  102 . The evaporator device  112  is adapted to transfer thermal energy from exhaust gases to the working fluid that flows within the evaporator device  112 . 
     The turbine  114  is in fluid communication with the evaporator device  112  and is disposed downstream of the evaporator device  112 . The heated working fluid from the evaporator device  112  flows to the turbine  114  and rotates the turbine  114 . More specifically, the heated working fluid rotates a blade-shaft arrangement (not shown) of the turbine  114  and is cooled. The blade-shaft arrangement (not shown) includes a shaft  120  that extends between the turbine  114  and the electrical generator  116 . 
     The electrical generator  116  is operatively connected to the turbine  114 . More particularly, the shaft  120  is connected to the turbine  114  at one end and forms a rotor of the electrical generator  116  at the other end. The electrical generator  116  converts rotational motion of the shaft  120  into electrical output. This electrical output can then be used to run the cooling system  108 . 
     The condenser  118  is in fluid communication with the turbine  114  and is disposed downstream of the turbine  114 . The fluid communication facilitates flow of the working fluid from the turbine  114  to the condenser  118 . The condenser  118  is adapted to condense the working fluid that flows through the condenser  118 , which is then recirculated in the energy recovery system  106 . 
     During normal operation of the machine system  100 , the condenser  118  may heat up and require to be cooled down for continuous operation. Similarly, the heat generating systems  104  may heat up during continuous operation of the machine system  100 . For example, an engine radiator may heat up during normal operation of the ICE  102 . Therefore, the cooling system  108  is installed to cool the condenser  118  and the heat generating systems  104 . 
     The cooling system  108  is integrated with the energy recovery system  106  and is adapted to cool the plurality of heat generating systems  104  and the condenser  118 . The cooling system  108  includes an energy storage apparatus  122 , a plurality of fans  124 , a condenser fan  126 , and a control unit  128 . 
     The energy storage apparatus  122  is electrically connected to the electrical generator  116 . The energy storage apparatus  122  is adapted to receive the electrical output from the electrical generator  116 . The energy storage apparatus  122  is adapted to supply a portion of the electrical output to the plurality of fans  124 , the condenser fan  126 , and the control unit  128 . In addition, the energy storage apparatus  122  is adapted to store extra amount of the electrical output for future use. 
     The plurality of fans  124  are electrically connected to the energy storage apparatus  122 , via the control unit  128 . The plurality of fans  124  are installed proximal to the plurality of heat generating systems  104 . Each of the plurality of fans  124  is powered by the electrical output from the energy storage apparatus  122  and is adapted to cool one or more of the plurality of heat generating systems  104 . In an embodiment, one of the plurality of fans  124  is adapted to cool one of the plurality of heat generating systems  104 . 
     Similar to the plurality of fans  124 , the condenser fan  126  is installed proximal to the condenser  118  of the energy recovery system  106 . The condenser fan  126  is also powered by the electrical output from the energy storage apparatus  122  and is adapted to cool the condenser  118 . 
     The control unit  128  is installed between the energy storage apparatus  122  and the plurality of fans  124 . The control unit  128  may be a combination of electrical components that perform in conjunction to selectively control each of the plurality of fans  124 . The control unit  128  includes a plurality of sensors that sense the load requirements of various heat generating systems  104 . For example, the control unit  128  may include a thermostat that senses the load requirement of one of the heat generating systems  104 , based on the temperature of the heat generating systems  104 . The control unit  128  selectively activates and deactivates one or more of the plurality of fans  124 , based on the load requirements of the corresponding heat generating system  104 . This enables power conservation by the cooling system  108 . Hence, the conserved energy may be used for continuous operation of the condenser fan  126 . This enables efficient operation of the condenser fan  126 . More specifically, the control unit  128  optimizes and maximizes heat transfer by the condenser fan  126  to the working fluid. 
     INDUSTRIAL APPLICABILITY 
     In operation, the energy recovery system  106  circulates the working fluid through the evaporator device  112 , the turbine  114 , and the condenser  118 , in a closed loop manner. More specifically, the fluid pump  110  circulates the working fluid through the evaporator device  112 , the turbine  114 , and the condenser  118 . 
     The evaporator device  112  receives exhaust gases from the internal combustion engine (ICE)  102  and working fluid from the fluid pump  110 . The evaporator device  112  transfers the thermal energy of the exhaust gases to the working fluid flowing through the evaporator device  112 . Thus, the working fluid is heated up to its gaseous form. The heated working fluid is then passed through the turbine  114 . 
     The turbine  114  is structured and arranged to convert thermal energy of the heated working fluid to a rotational motion of the shaft  120 . The rotational motion of the shaft  120  is then used by the electrical generator  116  to produce the electrical output. Moreover, the working fluid is cooled, while flowing through the turbine  114 . The working fluid is then passed through the condenser  118  to be condensed and recirculated. 
     The cooling system  108  is installed to cool the condenser fan  126  and the plurality of heat generating systems  104 . The cooling system  108  consists of a plurality of fans  124 . The plurality of fans  124  are powered by the electrical output produced by the electrical generator  116  and are adapted to cool the plurality of heat generating systems  104 . For example, the plurality of fans  124  may generate a flow of air through a radiator of the corresponding heat generating systems  104  to cool those heat generating systems  104 . 
     Similarly, the condenser fan  126  is also powered by the electrical output produced by the electrical generator  116  and is adapted to cool the condenser  118 . The condenser fan  126  may require a large amount of electrical output to run continuously and enable heat transfer through the condenser  118 . Therefore, the control unit  128  is installed to conserve energy from the plurality of fans  124 . The conserved energy is then used to run the condenser fan  126 . 
     The control unit  128  selectively controls each of the plurality of fans  124 , based on load requirements of the corresponding heat generating system  104 . More specifically, the control unit  128  may deactivate one or more of the plurality of fans  124 , when load requirement of the corresponding heat generating system  104  exceeds a predetermined value. The cooling process enables energy conservation. The conserved energy may then be used to run the condenser fan  126 . Therefore, the control unit  128  optimizes and maximizes heat transfer by the condenser fan  126  to the working fluid that flows in the condenser  118 . It may also be noted that the specific arrangement of dedicated fan  124  for each of the plurality of heat generating systems  104  require use of smaller cooling fans as compared to a single, bulky fan to cool the plurality of heat generating systems  104 . This improves packaging of the machine system  100 . Further, the energy conservation by the control unit  128  enables increased fuel economy of the machine system  100 . 
     It should be understood that the above description is intended for illustrative purposes only and is not intended to limit the scope of the present disclosure in any way. Those skilled in the art will appreciate that other aspects of the disclosure may be obtained from a study of the drawings, the disclosure, and the appended claim.