High Temperatures during compression

August 28, 2007, 08:18

Hello During the simulation of a compression stroke (RPM:3000/min, dp=4000bar) the resulting temperatures seem too high to me (dT=150K, static enthalpy,thermal). The temperature change should be in the range of 50K. In the Infol file the following warning appears:

*** WARNING #047 *** CONVERGENCE OF ENTHALPY TO TEMPERATURE NOT ACHIEVED AT 106159 CELLS.

MAXIMUM DIFFERENCE OF 0.266E+01 AT CELL 8272 Has anybody an advice for me?

Thanks John

August 28, 2007, 09:42

I am using the following specht.f-user-coding:

CP=(0.0032 * T) * 1000

RETURN

END

August 29, 2007, 03:42

use CONVTE.F subroutine h(t) user coding. Set H and DH/DT

August 28, 2007, 08:18	High Temperatures during compression	#1
John Guest Posts: n/a	Hello During the simulation of a compression stroke (RPM:3000/min, dp=4000bar) the resulting temperatures seem too high to me (dT=150K, static enthalpy,thermal). The temperature change should be in the range of 50K. In the Infol file the following warning appears: * WARNING #047 * CONVERGENCE OF ENTHALPY TO TEMPERATURE NOT ACHIEVED AT 106159 CELLS. MAXIMUM DIFFERENCE OF 0.266E+01 AT CELL 8272 Has anybody an advice for me? Thanks John

August 28, 2007, 09:42	Re: High Temperatures during compression	#2
John Guest Posts: n/a	I am using the following specht.f-user-coding: CP=(0.0032 * T) * 1000 RETURN END

August 29, 2007, 03:42	Re: High Temperatures during compression	#3
Denizen Guest Posts: n/a	use CONVTE.F subroutine h(t) user coding. Set H and DH/DT

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