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Light Water Approximations - Errata

"Approximate Functions for the Fast Calculation of Light-Water Properties At Saturation",

1. p.346, under the heading "Dynamic viscosity, liquid phase at saturation": The units given "[10^(-6) kg/(m.s)]" could also be read as: [MPa.s]

2. p.346, "Visc(l) = 64.0-0.00261596*exp(0.4010038)*P" (last equation of the section) should read
   Visc(l) = 64.0-0.00261596*exp(0.4010038 *P)

3. p.346, the equation for Visc(l) in the range of 18.868 MPa <= P < 20.430 MPa (second last equation of the section) has a maximum error of 0.50% in this range.

"Simple Functions for the Fast Approximation of Light Water Thermodynamic Properties",

1. p.26, sec 4.4, the last equation of the section has a range given as:
   "18.079 MPa <= P(s) <= 20.300 MPa"; this should read
   "18.079 MPa < P(s) <= 21.500 MPa"; (note TWO changes)
   however, the computer codes that have been released set the pressure to 18 MPa if the given pressure is higher than 18 MPa. Thus the value that will be returned will be erroneous. In addition, the ranges given should be:
   "0.030 MPa < P(s) <= 0.671 MPa"
   "0.671 MPa < P(s) <= 2.606 MPa"
   "2.606 MPa < P(s) <= 6.489 MPa"
   "6.489 MPa < P(s) <= 11.009 MPa"
   "11.009 MPa < P(s) <= 14.946 MPa"
   "14.946 MPa < P(s) <= 18.079 MPa"
   "18.079 MPa < P(s) <= 21.500 MPa"
   

2. p.27, sec 5.2 the equation for h(P, T) is given. The denominator of one of the fractions reads:
   "SQRT(7.4529x10^(-0.6)*T^(3) - P^(2))"; this should read
   "SQRT(7.4529x10^(-6)*T^(3) - P^(2))". Also -2.225 should read +2.225.

3. p.27, sec 5.2 the third range equation,
   "h(g)=-7.835986(3.001-P)^(2.0) + 2.934312(3.001-P) + 2803.71" should read
   "h(g)=-7.835986(P-3.001)^(2.0) - 2.934312(P-3.001) + 2803.71" (for the sake of consistency)

4. p.27, sec 5.2 the second last equation,
   "h(g)=-3.532177(P-8.00)^(2.0) + 29.81305(P-8.00) + 2.565.00" should read
   "h(g)=-3.532177(P-8.00)^(2.0) + 29.81305(P-8.00) + 2565.00"

5. p.28, sec 5.3, the first range given reads:
   "for 0.025 MPa <= p <= 1.480 MPa;" but should read:
   "for 0.025 MPa <= P <= 1.480 MPa;"

6. p.28, sec 5.4, the passage that reads
   "They are valid in the range from 0.070 MPa - 20.4 MPa, and from saturation to 400 C. The error is less than 5%." should read:
   "The equations given are valid in the range from 0.050 MPa - 20.4 MPa, and from saturation to 400 C. When the pressure is above 0.070 MPa, the error is less than 5%; when the pressure is less than 0.070 MPa, the error is slightly higher than 5%." Also, in the two highest pressure ranges, 7.620756 should be 7.620756x10^(-3) and 6.5162612 should be 6.5162612x10^(-6).

7. p.29, equation 12 reads "(dF/dP) (T const) + (dF(g)/dP) ..."
   but should read "(dF/dP) (T const) = (dF(g)/dP) ..."

8. p.29, equation 13 has the final term
   "(dR/dT) (T const) * [T-T(P)]" but should read
   "(dR/dT) (P const) * [T-T(P)]"

9. p.32, Appendix I, the equations given have been updated in the third paper (Garland et al) and the user should note the corrections below.

10. p.33 Appendix III, the subcooled equations given under the specific volume section are actually equations for density (the inverse of specific volume). The superheated equations are correct as stated.

11. p.33 Appendix III, the superheated (dv/dP)T equation has, in its final term,
    "(0.12/(T+100)-0.00106)P^(-1.1)" in the numerator; this should read
    "(0.12/(T+100)-0.00106)P^(1.1)"

12. p.33 Appendix III, the superheated (dv/dT)P equation has, in the first part of its third term,
    "(0.12/(T+100))P^(-0.1)" in the numerator; this should read
    "(0.12/(T+100)^2)P^(0.1)" Note there are TWO changes given here.

13. p.33 Appendix III, the superheated (dv/dT)P equation has, in the second part of its third term,
    "(0.12/(T+100)-0.00106)P^(-0.1)" in the numerator; this should read
    "(0.12/(T+100)-0.00106)P^(0.1)"

14. p.33 Appendix III, the superheated (dh/dP)T equation has, in its second term,
    "0.28exp(-0.008(T-162))*(-100/T)"; this should read
    "0.28exp(-0.008(T-162))-100/T"

15. p.33 Appendix III, the superheated (dh/dT)P equation has, in its second term,
    "0.28exp(-0.008(T-1762))"; this should read
    "0.28exp(-0.008(T-162))"

16. p.34 Appendix III, the superheated (ds/dP)T equation has, in its second term,
    " [ .... - 4.125x10^(-6) - T + 0.0052]"; this should read
    " [ .... - 4.125x10^(-6)*T + 0.0053]" (note there are TWO corrections)

17. p.34 Appendix III, the subcooled (ds/dT)P equation has, in its second term,
    "dP/dT* (dS/dT + 0.325/(370-T) - 0.004)"; this should read
    "dP/dT* (dS/dP + 0.325/(370-T) - 0.004)".

"Extensions to the Approximation Functions for the Fast Calculation of Saturated Water Properties",

1. p.384, Table A-1, Saturation pressure is given as a function of temperature. The ranges should be corrected as follows:
   "17.511 <= T <= 56.275" should be "17.511 <= T < 56.275";
   "203.662 <= T < 299.407" should be "203.662 <= T <= 299.407";
   "299.407 <= T < 355.636" should be "299.407 < T < 355.636"
   to make them consistent with the computer code.

2. p.386, Note 3 of Table A-6, the equation reads
   "C(P)=38485636.1747-7311152.45563P+520882.9814112P^(2)+16494.9064728P^(3)+195.8985209777P^(4)", but should read
   "C(P)=38485636.1747-7311152.45563P+520882.9814112P^(2)-16494.9064728P^(3)+195.8985209777P^(4)"
   Note also that these equations have NOT been implemented in the computer code generated by Dr. Garland.
   
3. p.387, Table A-9, the last pressure range reads
   "20.000 <= P <= 21.50..." but should read
   "20.000 < P <= 21.50...". Since the functions are continuous at the range interfaces, it should not affect the value calculated either way.
   
4. p.388, Table A-10, Note 1 is incorrectly truncated. It reads
   "C(P) = 1.8720218136 + 5.19125176488 P - 136.166377842 P^2 + 2364.55677 P^3 - 16088", but should read
   " C(P) = 1.8720218136 + 5.19125176488 P - 136.166377842 P^2 + 2364.55677 P^3 - 16088.8064372 P^4"
   Note also that these equations have NOT been implemented in the computer code generated by Dr. Garland.