Endress+Hauser Proline Prowirl 73 - Page 155

Proline Prowirl 73 Description of device functions
Endress+Hauser 155
REFERENCE GROSS
CALORIFIC VALUE
Prerequisite
The function is only available if NATURAL GAS AGA8 Gross Method 1 or NATURAL
GAS SGERG-88 was selected in the NATURAL GAS EQUATION function (ä 149).
Description
Use this function to enter the reference gross calorific value of the natural gas. The
following reference operating conditions apply: reference temperature 0°C, reference
pressure 1.013 bar abs, reference combustion temperature 25°C. The reference gross
calorific value is used for the calculation of the compressibility of the natural gas with the
natural gas equations AGA8 Gross Method 1 and SGERG-88.
User input
5-digit floating-point number
Unit
The corresponding unit is taken from the UNIT CALORIFIC VALUE CORRECTED
VOLUME function.
Factory setting
34 MJ/Nm
3
TYPE CALORIFIC
VALUE
Prerequisite
The function is only available if the following was selected in the SELECT FLUID
function (ä 143):
• NATURAL GAS
•METHANE
• USER DEFINED LIQUID
• GAS MIXTURE
Description
Use this function to define the type of unit for the net calorific values and gross calorific
values:
• "per mass", e.g. MJ/kg
• "per corrected volume", e.g. kBtu/SCF
Options
MASS
CORRECTED VOLUME
Factory setting
CORRECTED VOLUME
GROSS CALORIFIC
VALUE
Prerequisite
The function is only available if the following was selected in the SELECT FLUID
function:
•METHANE
• USER DEFINED LIQUID with COMBUSTION option in the 
ENERGY CALCULATION function
• GAS MIXTURE
or if the selection NATURAL GAS and one of the following NATURAL GAS EQUATION
was selected in the SELECT FLUID section:
• AGA8-DC92
• ISO 12213-2
• AGA8 Gross Method 1
•SGERG 88
Description
• A gross calorific value, which is used to calculate the heat flow, can be entered here
for USER DEFINED LIQUIDS.
• The gross calorific value of the gas is displayed here in the other cases described. The
gross calorific value is calculated as per ISO 6976-1995.
!
Note!
Make sure that the correct reference combustion temperature was entered (ä 153)
User input/user interface
5-digit floating-point number
Factory setting
40MJ/kg ; the corresponding unit is taken from the UNIT CALORIFIC VALUE MASS or
UNIT CALORIFIC VALUE CORRECTED VOLUME function.
Function description, FLOW COMPUTER group