Compared to Glycols LR

Paratherm LR™ vs. Ethylene Glycol and Propylene- Glycol Solutions — Comparison of Heat Transfer Coefficients

Physical Properties

		Paratherm LR					Propylene Glycol**					Ethylene Glycol**
Temp*		Density*	ThermalConduct.*	Viscosity*	Spec.Heat		Dens.	Therm.Cond.	Visc.	Spec.Heat		Dens	Therm.Cond.	Visc	Spec.Heat
50		6.4	0.088	2.1	0.47		8.9	0.206	10.7	0.80		9.1	0.215	5.5	0.74
-4		6.6	0.090	5.0	0.44		9.0	0.193	73.0	0.77		9.2	0.199	22.1	0.71
-22		6.7	0.090	7.3	0.43		9.0	0.188	172.8	0.76		9.3	0.193	44.0	0.70
		*Density, lb/gal*Thermal Conductivity,        BTU/(hr- ft²-°F/ft)*Viscosity, cP*Specific Heat, Btu/(lb-°F) *Temperature, ºF					**All data pertaining to Propylene and Ethylene glycol was obtained from Dow literature for the Dowfrost HD and Dowtherm 4000 @ 50% by Volume respectively

Fluid Film Coefficient – hi***

	Temp		Paratherm LR	Propylene Glycol	Ethylene Glycol
	50		157	199	277
	-4		106	77	137
	-22		89	51	97
Based on 3/4″ Sch. 40 pipe @ 4′/sec.***hi, BTU/(hr-ft²-°F)

Conclusions:

• At 50°F, glycol solutions have higher coefficients
• At -4°F, LR has a higher coefficient than Propylene Glycol solution
• At -22°F, LR has almost the same coefficient as Ethylene Glycol solution