Replication of VBA ASTM C680 Program
- Peter Pham
- 18 thg 4
- 2 phút đọc
ASTM C680 standard practice provides the algorithms and calculation methodologies for predicting the heat loss or gain and surface temperatures of certain thermal insulation systems that can attain one dimensional, steady- or quasi-steady-state heat transfer conditions in field operations.
This standard practice is based on the assumption that the thermal insulation systems can be well defined in rectangular, cylindrical or spherical coordinate systems and that the insulation systems are composed of homogeneous, uniformly dimensioned materials that reduce heat flow between two different temperature conditions.
The procedures used in this standard practice are based on standard, steady-state, one dimensional, conduction heat transfer theory. Heat flux solutions are derived for temperature dependent thermal conductivity in an insulation material.
The analysis procedure outlined in ASTM C680 standard practice is based on the following assumptions:
1. The thermal insulation is homogeneous
2. The system operating temperature is known
3. The insulation thickness is known
4. The surface transfer conductance of the system is known
5. The thermal conductivity as a function of temperature for each system layer is known in detail
We have replicated an Excel VBA program based on ASTM C680 standard practice. This program served as a guide for calculation of the heat loss or gain and surface temperatures of insulation systems. The range of application of these programs and the reliability of the output is a primary function of the range and quality of the input data.
Our VBA program supports up to four layers of insulation and includes the same surface geometries as the ASTM C680 program: horizontal pipe/cylinder, vertical pipe/cylinder, vertical flat surface, tank top, and tank bottom.
New insulation materials and their properties can be added in a separate Excel sheet.
This program can also generate a report as a text file in the same folder where the Excel program is located.
You can download the VBA program from the link below:
The VBA project is secured with a password. If you need access, kindly reach out to us here
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