Elastohydrodynamic Lubrication in Extended Parameter Ranges—Part IV: Effect of Material Properties©

Figures & data

TABLE 1 Comparison of Film Thickness Results from Different Viscosity Models

					H c (10^−4)
Case No.	U* (10^−10)	W* (10^−5)	P H (GPa)	k	Barus	Power	Roelands	Two Slope
1	3.44756	0.25195	1.0777	1	1.25617	1.19969	1.21681	1.28038
2	0.57459	1.00781	1.7108	1	0.37804	0.36755	0.35336	0.37489
3	0.14365	1.00781	1.7108	1	0.12714	0.12324	0.11989	0.12636
4	0.14365	0.25995	0.6789	3	0.23155	0.22628	0.22516	0.23142
5	3.44756	36.1621	2.7157	6	1.43056	1.39272	1.33609	1.42125

FIG. 1(a) Effect of pressure-viscosity coefficient at different loads and speeds (K = 1). Results at k = 1 and P _H = 0.6789 GPa.

FIG. 1(b) Results at k = 1 and P _H = 1.078 GPa.

FIG. 1(c) Results at k = 1 and P _H = 1.711 GPa.

FIG. 1(d) Results at k = 1 and P _H = 2.716 GPa.

FIG. 1(e) Results at k = 1 and P _H = 1.0777 GPa (linear scales for α and G*).

FIG. 2(a) Effect of pressure-viscosity coefficient at different loads and speeds (K = 8). Results at k = 8 and P _H = 1.0777 GPa.

FIG. 2(b) Results at k = 8 and P _H = 1.7108 GPa.

FIG. 3 Sample curve fitting results.

TABLE 2 Curve Fitting Results for Exponent D Under Different Conditions

		Exponent D
Ellipticity	P H (GPa)	U = 15 m/s	U = 2.5 m/s	U = 0.625 m/s	U = 0.10 m/s
1	0.6789	0.46579	0.52056	0.59978	0.60697
	1.0777	0.47767	0.53258	0.62743	0.72510
	1.7108	0.53894	0.65409	0.71857	1.17860
	2.7156	0.64644	0.74928	1.05429	2.19926
8	1.0777	0.61532	0.62332	0.65478	0.79766
	1.7108	0.62392	0.68096	0.78276	1.26071

FIG. 4(a) Effect of effective elastic modulus at different loads and speeds. Results at k = 1 and W = 200 N.

FIG. 4(b) Results at k = 1 and W = 800 N.

FIG. 4(c) Results at k = 8 and W = 2435.3 N.

FIG. 4(d) Results at k = 8 and W = 9741 N.

TABLE 3 Curve-Fitting Results for Exponent Q Under Different Conditions

		Exponent Q
Ellipticity	P H (GPa)	U = 15 m/s	U = 2.5 m/s	U = 0.625 m/s	U = 0.10 m/s
1	1.0777	−0.17531	−0.16446	−0.07312	0.06703
	1.7108	−0.15266	−0.05821	0.06305	0.78420
8	1.0777	−0.11608	−0.08873	−0.04639	0.16984
	1.7108	−0.06255	−0.00780	0.14680	1.05229
	2.7156	0.00626	0.21829	0.95015

FIG. 5 Sample solutions at different pressure-viscosity coefficients. U* = 0.14365E-10, W* = 0.10078E-4, k = 1, E′ = 219.78 GPa, P _H = 1.711 GPa.

FIG. 6 Sample solutions at different effective elastic moduli. U = 2.5 m/s, W = 800 N, k = 1, α = 18.2 GPa⁻¹.