Reductant tank as a heat storage device

Patent metadata

Field	Value
Publication number	US-10487708-B2
Application number	US-201715418617-A
Country	US
Kind code	B2
Filing date	Jan 27, 2017
Priority date	Feb 10, 2016
Publication date	Nov 26, 2019
Grant date	Nov 26, 2019

Abstract

A method for operating an engine system is provided. The method includes during a first operating condition, flowing oil from an oil sump to a heat exchanger attached to a reductant tank and transferring heat from oil flowing through the heat exchanger to reductant stored in the reductant tank. The method further includes during a second operating condition, flowing oil from the oil sump to the heat exchanger and transferring heat from the reductant stored in the reductant tank to oil flowing through the heat exchanger.

First claim

The invention claimed is:

1. A method for heat management in a system of an internal combustion engine comprising:
during a first operating condition, flowing an oil from an oil sump to a heat exchanger attached to a reductant tank and transferring heat from the oil flowing through the heat exchanger to a reductant stored in the reductant tank;
during the first operating condition, flowing coolant from an engine coolant conduit extending through the internal combustion engine to the heat exchanger through operation of a coolant control valve coupled to the engine coolant conduit and a coolant line, where the coolant line is coupled to the heat exchanger, and transferring heat from coolant to a reductant solution in the heat exchanger;
during the first operating condition, correspondingly adjusting a flowrate of the coolant delivered to the heat exchanger and a flowrate of the oil delivered to the heat exchanger based on engine operating conditions;
during a second operating condition, flowing the oil from the oil sump to the heat exchanger and transferring heat from the reductant stored in the reductant tank to the oil flowing through the heat exchanger; and
during the second operating condition, flowing the coolant from the engine coolant conduit extending through the internal combustion engine to the heat exchanger through operation of the coolant control valve coupled to the engine coolant conduit and the coolant line, the coolant line transferring heat from the reductant solution to the coolant in the heat exchanger;
where correspondingly adjusting the flowrates of the coolant and the oil delivered to the heat exchanger includes decreasing coolant flow through the heat exchanger through operation of the coolant control valve while increasing oil flow through the heat exchanger through operation of an oil control valve.

2. The method of claim 1 , wherein the reductant tank stores heat energy which is transferred from the oil to the reductant solution when a temperature of the oil is higher than that of the reductant solution.

3. The method of claim 1 , wherein the reductant tank releases heat energy by transferring energy from the reductant solution to the oil when a temperature of the reductant solution is higher than that of the oil.

4. The method of claim 1 , wherein the reductant tank has at least one recess in at least one side and wherein the heat exchanger is accommodated in the at least one recess of the reductant tank.

5. The method of claim 1 , wherein the heat exchanger is arranged on at least one outer side of the reductant tank.

6. The method of claim 1 , wherein a reductant line, in which at least one reductant pump is arranged, is arranged between the reductant tank and an injection device for introducing the reductant solution into an exhaust tract of the internal combustion engine, wherein at least one branch line for returning the reductant solution to the reductant tank branches off from the reductant line, wherein the branch line runs through the heat exchanger, and wherein the method further comprises circulating the reductant solution through the heat exchanger using the reductant pump.

7. An engine system comprising:
a reductant tank storing a reductant solution coupled to an injection device configured to inject the reductant solution into an exhaust tract;
an engine lubrication system including an oil sump;
an oil circuit including,
a first oil line coupled to the oil sump and an oil control valve,
a second oil line coupled to the oil control valve and a heat exchanger, where the heat exchanger is attached to the reductant tank,
a third oil line coupled to the heat exchanger and the engine lubrication system, and
a bypass oil line coupled to the oil control valve and the engine lubrication system bypassing the heat exchanger;

an engine coolant conduit extending through an internal combustion engine and a coolant control valve coupled to the engine coolant conduit and a coolant line, where the coolant line is coupled to the heat exchanger; and
a control system configured to:
adjust the oil control valve based on one or more engine operating conditions to alter an amount of an oil flowing to the heat exchanger; and
adjust the coolant control valve to alter a flowrate of a coolant to the heat exchanger based on a flowrate of the oil delivered to the heat exchanger.

8. The engine system of claim 7 , where the control system is configured to, during a first operating condition, command the oil control valve to flow oil from the oil sump to the heat exchanger to transfer heat from oil flowing through the heat exchanger to the reductant solution stored in the reductant tank and during a second operating condition, command the oil control valve to flow oil from the oil sump to the heat exchanger to transfer heat from the reductant solution stored in the reductant tank to oil flowing through the heat exchanger.

9. The engine system of claim 8 , where the control system is configured to correspondingly adjust the flowrate of the coolant and the flowrate of the oil delivered to the heat exchanger based on engine temperature.

10. A method for operating an engine system comprising:
during a first operating condition, flowing an oil from an oil sump to a heat exchanger attached to a reductant tank and transferring heat from the oil flowing through the heat exchanger to a reductant stored in the reductant tank;
during the first operating condition, flowing coolant from an engine coolant conduit extending through an internal combustion engine to the heat exchanger through operation of a coolant control valve coupled to the engine coolant conduit and a coolant line, where the coolant line is coupled to the heat exchanger, and transferring heat from coolant to a reductant solution in the heat exchanger;
during the first operating condition, correspondingly adjusting a flowrate of the coolant delivered to the heat exchanger and a flowrate of the oil delivered to the heat exchanger based on engine operating conditions;
during a second operating condition, flowing the oil from the oil sump to the heat exchanger and transferring heat from the reductant stored in the reductant tank to the oil flowing through the heat exchanger; and
during the second operating condition, flowing the coolant from the engine coolant conduit extending through the internal combustion engine to the heat exchanger through operation of the coolant control valve coupled to the engine coolant conduit and the coolant line, the coolant line transferring heat from the reductant solution to the coolant in the heat exchanger;
where correspondingly adjusting the flowrates of the coolant and the oil delivered to the heat exchanger includes increasing coolant flow through the heat exchanger through operation of the coolant control valve while decreasing oil flow through the heat exchanger through operation of an oil control valve.

11. The method of claim 10 , further comprising during a third operating condition inhibiting oil flow from the oil sump to the heat exchanger, where the third operating condition temporally occurs between the first operating condition and the second operating condition.

12. The method of claim 10 , where the first operating condition includes a condition where a temperature of the oil is greater than a temperature of the reductant stored in the reductant tank and where the second operating condition includes a condition where a temperature of the engine oil is less than a temperature of the reductant stored in the reductant tank.

Assignees

• Ford Global Tech Llc

Inventors

• Mehring Jan
• Lorenz Thomas
• Quix Hans Guenter
• Linsel Jan
• Springer Moritz Klaus
• Huth Florian

Classifications

• F01N2610/1406

  Storage means for substances, e.g. tanks or reservoirs · CPC title

• F01N3/2066

  Selective catalytic reduction [SCR] · CPC title

• F01M5/021 Primary

  by heating · CPC title

• F28D20/0034 Primary

  using liquid heat storage material · CPC title

• F01M5/001

  Heating · CPC title