US 11,725,560 B2
Heater control in heavy-duty motor vehicle engines
Cynthia Chaffin Webb, Sedro-Woolley, WA (US); Charles Wayne Reinhardt Swart, Bellingham, WA (US); Maarten Meijer, Anacortes, WA (US); Varun Ramesh, Bellingham, WA (US); and John Lahti, Anacortes, WA (US)
Assigned to PACCAR INC, Bellevue, WA (US)
Filed by PACCAR Inc, Bellevue, WA (US)
Filed on Aug. 25, 2020, as Appl. No. 17/2,511.
Claims priority of provisional application 63/057,090, filed on Jul. 27, 2020.
Claims priority of provisional application 63/056,131, filed on Jul. 24, 2020.
Claims priority of provisional application 63/054,468, filed on Jul. 21, 2020.
Prior Publication US 2022/0025805 A1, Jan. 27, 2022
Int. Cl. F01N 3/00 (2006.01); F01N 3/20 (2006.01); F01N 3/035 (2006.01); F01N 3/28 (2006.01)
CPC F01N 3/2066 (2013.01) [F01N 3/035 (2013.01); F01N 3/2892 (2013.01); F01N 2240/20 (2013.01); F01N 2570/14 (2013.01); F01N 2610/02 (2013.01); F01N 2610/146 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method, comprising:
operating a diesel engine of a heavy-duty truck such that the diesel engine generates an exhaust gas flow; and
while operating the diesel engine, operating an exhaust after-treatment system of the heavy-duty truck to maintain a temperature of the exhaust gas flow at a selective catalytic reduction system of the exhaust after-treatment system at a constant target temperature;
wherein operating the exhaust after-treatment system to maintain the temperature at the constant target temperature includes calculating a rate at which heat energy is provided from the diesel engine to the exhaust gas flow, calculating a target rate of heat energy for the exhaust gas flow at the selective catalytic reduction system based on the constant target temperature, calculating a supplemental heat rate at which to provide supplemental heat energy from a heater of the exhaust after-treatment system to the exhaust gas flow based on the calculated rate at which heat energy is provided from the diesel engine to the exhaust gas flow and the calculated target rate of heat energy, and operating the heater to provide supplemental heat energy to the exhaust gas flow at the calculated supplemental heat rate,
wherein calculating the rate at which heat energy is provided from the diesel engine to the exhaust gas flow includes averaging a product of a temperature of the exhaust gas flow as it enters the exhaust after-treatment system, a mass flow rate of the exhaust gas flow, and a molar specific heat of the exhaust gas flow across a moving average window of time.