Copyright: Department of Energy Engineering, Technical University of Denmark
Citation: Copyright © Department of Energy Engineering, Technical University of Denmark


Refrigerant Calculator

Refrigerant calculator is a simple program sitting on the Win95 / NT4 tool tray: .

To activate the program:

•	double-click on the icon:

•	Right-click on the icon [image] and select the Show menu.

To close the program:

•	Right-click on the icon [image] and select the Exit menu.

After activation the following dialog appears:

The following symbols are used:

•	T: temperature in °C or Kelvin

•	p: pressure in Bar or kPa

•	v: specific volume in m^3/kg

•	h: enthalpy in kJ/kg

•	s: entropy in J/(kg K)

•	h_lg: heat of evaporation in kJ/kg

•	Con: Conductivity in W/(m K)

•	Visc: Viscosity in (N s)/m^2

You start by specifying refrigerant and pressure and temperature unit.

To do calculations you find the button that will calculate what you want, specify the variables indicated on the button and press the button. The result will be transfered to the edit boxes.

For example:

You want to calculate enthalpy (h) in the gas area for R134a.

Select R134a in the list.

You find that there is two ways of calculating enthalpy, either as function of T and p or as function of T and v.

You know entropy and pressure, so you can't immediately use one of the two buttons.

Start by inputting pressure in the p editbox (for example 4 bar) and entropy in the s editbox (for example 1900 J/(kg K)).

Press the T,v (s,p) button and you will find that the temperature is 67.65 °C and specific volume is 0.06586 m^3/kg.

Now you can press either the "h (T,p)" or the "h (T,v)" button to find the enthalpy which is 458.98 kJ/kg.

Pressing the "Add refrigerant info" button transfers info on the selected refrigerant to the edit window.

Pressing the "Add point" button adds the calculated values to the edit window.

Pressing the "Clear" button clears the edit window.

Pressing the "Save" button saves the contents of the edit window to a text file.

Pressing the "Copy" button copies the contents of the edit window to the clipboard.

Pressing the "Print" button prints the contents of the edit window.

Pressing the "Hide" button hides the dialog.

Copyright ©	Department of Energy Engineering

Energy Systems Group

Refrigeration

Technical University of Denmark

Programmed by:

Morten Juel Skovrup

Additional code supplied by:

H.J.H. Knudsen

Address:	Technical University of Denmark

Department of Energy Engineering

Att. Morten Juel Skovrup

Building 402

2800 Lyngby

Denmark

e-mail:	ms@et.dtu.dk

This program is freeware. You may freely copy and use it without any charge. This program must not be sold for profit.

Disclaimer:

THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL Department of Energy Engineering or any person mentioned above BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.