It looks as though you have two conversions. The thermistor is a transducer which changes its resistance (non-linearly) with temperature. The bridge is a signal conditioner which converts that resistance to a voltage. Then your data acquisition system converts the voltage into a number.
What I think you are asking is for the further conversion of that number (representing volts, and indirectly resistance and temperature) to another number representing flow. I doubt you will find a LV program sitting around to do what you want because there are too many variables and complex relationships among them to do the conversion in any sort of universal manner. Things like the package style of the thermistor, whether the flow is laminar or turbulent, etc., play a role.
The thermistor data sheet should give some data about the thermal transfer rates at various flow rates. If it does not, you will need to make a series of calibration runs. Any system of this type will need to be calibrated after assembly because too many unknowns exist to design them all out.
Lynn
