METHOD OF PRE-HEATING A INTERNAL COMBUSTION ENGINE BY OIL AND JACKET WATER COOLER

Abstract

Provided is an internal combustion engine, comprising at least one cooling device for cooling at least one operational liquid of the internal combustion engine during and/or after operation of the internal combustion engine. The at least one cooling device has at least one heat exchanger and lines for transporting the at least one operational liquid to and from the at least one heat exchanger. The heat exchanger exchanges heat with a cooling medium, which cooling medium has during the operation of the internal combustion engine a lower temperature than the at least one operational liquid of the internal combustion engine. Heat is exchanged by the heat exchanger between the at least one operational liquid and the cooling medium, which cooling medium has before and/or during a starting operation of the internal combustion engine a higher temperature than the at least one operational liquid of the internal combustion engine.

Claims

1. An internal combustion engine, comprising: at least one cooling device for cooling at least one operational liquid of the internal combustion engine during and/or after operation of the internal combustion engine, wherein the at least one cooling device has at least one heat exchanger and lines for transporting the at least one operational liquid to and from the at least one heat exchanger; and the heat exchanger, wherein the heat exchanger exchanges heat with a cooling medium, which cooling medium has during the operation of the internal combustion engine a lower temperature than that of the at least one operational liquid of the internal combustion engine; wherein during and/or before a starting operation of the internal combustion engine the cooling device is configured to pre-heat the internal combustion engine by the heat exchanger exchanging heat between the at least one operational liquid and the cooling medium, which cooling medium has before and/or during a starting operation of the internal combustion engine a higher temperature level than that of the at least one operational liquid of the internal combustion engine.

2. The internal combustion engine as set forth in claim 1, further comprising at least one pump, wherein the pump is configured to pump the at least one operational liquid to and from the at least one cooling device before and/or during the starting operation of the internal combustion engine.

3. The internal combustion engine as set forth in claim 2, wherein the at least one pump is provided at a bypass line, wherein the bypass line can be fluidically connected to the at least one heat exchanger before and/or during the starting operation of the internal combustion engine.

4. The internal combustion engine as set forth in claim 1, wherein at least two cooling devices are provided for cooling the at least one operational liquid of the internal combustion engine, wherein a first of the at least two cooling devices is configured to cool at least one cooling water circuit of the internal combustion engine, wherein a second of the at least two cooling devices is configured to cool at least one oil circuit of the internal combustion engine, and wherein the at least one cooling water circuit and the at least one oil circuit of the internal combustion engine can be heated by the at least two cooling devices before and/or during the starting operation of the internal combustion engine.

5. The internal combustion engine as set forth in claim 1, further comprising at least one further cooling device for at least one external component of the internal combustion engine, wherein the at least one further cooling device is configured to heat the at least one further component of the internal combustion engine before and/or during the starting operation of the internal combustion engine.

6. The internal combustion engine as set forth in claim 5, wherein the at least one external component of the internal combustion engine is a turbo charger and/or an intercooler and/or a fuel cooler.

7. A method for pre-heating an internal combustion engine, the method comprising: cooling with at least one cooling device and a cooling medium at least one operational liquid of the internal combustion engine during and/or after operation of the internal combustion engine, wherein the cooling medium has during the operation of the internal combustion engine a lower temperature than that of the at least one operational liquid of the internal combustion engine; and using the at least one cooling device and the cooling medium before and/or during a starting operation of the internal combustion engine to pre-heat the internal combustion engine, wherein the cooling medium has before and/or during the starting operation of the internal combustion engine a higher temperature than that of the at least one operational liquid of the internal combustion engine.

Description

[0017] Further details and advantages of the present invention will be described with reference to the specific description hereinafter. In the drawing:

[0018] FIG. 1 shows an embodiment of an internal combustion engine having a cooling device as known from the state of the art,

[0019] FIG. 2 shows an embodiment of an internal combustion engine having a cooling device as shown in the state of the art during pre-heating, and

[0020] FIG. 3 shows an embodiment of an internal combustion engine according to the invention.

[0021] FIG. 1 shows an internal combustion engine 1 having a cooling device 2 as known from the state of the art. More particularly, the internal combustion engine 1 shown in FIG. 1 has two cooling devices 2. By the line 4 cooling water of the internal combustion engine 1 can be led from the internal combustion engine 1 (connection point 4.1) to a heat exchanger 3 and from the heat exchanger 3 back to the internal combustion engine 1 (to the connection point 4.2 of the internal combustion engine 1). A pump 6 is provided in the line 4 leading the cooling water circuit of the internal combustion engine 1 back to the internal combustion engine 1, which pump 6 is driven by the internal combustion engine 1 and keeps the cooling water circuit during the operation of the internal combustion engine 1 in motion. By using line 5 oil of the internal combustion engine 1 can be led from the internal combustion engine 1 (connection point 5.1) to a heat exchanger 3 and from the heat exchanger 3 back to the internal combustion engine 1 (to the connection point 5.3 of the internal combustion engine 1). Furthermore, two heat exchangers 3 are provided for a line 10 and a line 11, which lines 10 and 11 could for example be used to cool external components of the internal combustion engine (i.e. a turbo charger or an intercooler). The heat exchangers 3 exchange heat with the line 8, which line 8 is provided for guiding a cooling medium. This cooling medium is used to remove heat from the internal combustion engine 1. The removed heat of the internal combustion engine 1 can be usedfor exampleby a thermal power plant. The flow directions of the circuits through lines 4, 5 and 8 are shown by arrows. There are bypass lines 7 arranged parallel to the lines 4, 5. Those bypass lines 7 include at least one pump 6 and at least one pre-heating device 9. A check valve 12 is arranged in the line 4 of the cooling water circuit to ensure a flow direction of the cooling water circuit during a bypass operation during a pre-heating of the internal combustion engine 1.

[0022] FIG. 2 shows an internal combustion engine 1 according to the state of the art (the same internal combustion engine 1 as shown in FIG. 1) during a pre-heating operation, which can be done before and/or during a starting operation of the internal combustion engine 1. During the pre-heating of the internal combustion engine 1 the flow of the oil and the cooling water can be redirected through pre-heating devices 9. In more detail, during a pre-heating operation the cooling water is lead through a bypass line 7, which bypass line comprises a pump 6 and a pre-heating device 9. The pump 6 is driven by an independent drive (not shown in the figures), because usually during a pre-heating operation the internal combustion engine 1 is not active and therefore a separate pump 6 with an independent drive is necessary to move the cooling water circuit. The pre-heating device 9 could for example be an electrical heating device. After flowing through the bypass line 7 the cooling water is led back to the internal combustion engine 1 (to the connection point 4.2 of the internal combustion engine 1) by a further bypass line, which bypass line bypasses the heat exchanger 3. During a pre-heating operation of the internal combustion engine 1 the oil is lead flowing from a connecting point 5.2 of the internal combustion engine (for example a connecting point to the crankcase of the internal combustion engine 1) to a pump 6which is also driven by an independent driveto a pre-heating device 9 for oil and after flowing through this pre-heating device 9 back to the internal combustion engine (to the connection point 5.3 of the internal combustion engine 1) by the use of a bypass line, wherein the heat exchanger 3 can be bypassed. The flow of the oil and the cooling water during a pre-heating operation of the internal combustion engine 1 is shown by the thick lines of FIG. 2.

[0023] FIG. 3 shows an embodiment of an internal combustion engine 1 according to the invention during a pre-heating operation, wherein during and/or before a starting operation of the internal combustion engine 1 the cooling device 2 is configured to pre-heat the internal combustion engine 1, wherein heat is exchanged by the heat exchanger 3 between the operational liquid and a cooling medium. More specific, the embodiment of FIG. 3 shows a pre-heating of the internal combustion engine 1 during and/or before a starting operation of the internal combustion engine 1, wherein heat is provided from the cooling medium in line 8 to the cooling water in line 4 as well as from the cooling medium in line 8 to the oil circuit in line 5 by the heat exchangers 3. This is possible because the cooling medium in line 8 has a higher temperature level before and/or during the starting operation of the internal combustion engine 1 than the cooling water and the oil in lines 4, 5.

[0024] The oil circuit is driven during the pre-heating operation by a pump 6 arranged in a bypass line 7, which pump 6 is driven independently from the internal combustion engine 1 and is provided downstream of the connecting point 5.2. The cooling water circuit is driven during the pre-heating operation by a pump 6, which pump 6 is driven independently from the internal combustion engine 1 and is provided in the bypass line 7. The bypass line 7, which comprises the pump 6, can be bypassed after the starting operation during an operation of the internal combustion engine 1 by the cooling water circuit in line 4. Also, further external components of the internal combustion engine 1 can be pre-heated by the heat exchangers 3 and the lines 10 and 11. The sequence in which the cooling medium passes through the heat exchangers of the lines 4, 5, 10, 11 can be individually changed.