The Falling Film Evaporator model is used to simulate a typical Falling film evaporator.
The Liquor_In, Liquor_Out, Steam_In, Steam_Out and Condensate_Out streams are required. Post_Heater_Liquor_In , Post_Heater_Liquor_Out and Condensate_In streams are optional.
Specify the heat transfer Area and either the Dome Pressure or Heat Transfer Coefficient. If the Dome Pressure is given the Heat Transfer Coefficient is calculated. If the Heat Transfer Coefficient is given the Dome Pressure is calculated. The Energy Efficiency is required.
If the heat transfer Area is not given the available energy is transferred to the liquor side. The Liquor_Out and Steam_Out pressures are the Dome Pressure (if given) or the Liquor_In pressure.
If a post-heater is included specify either the Heat Transfer Coefficient and Area or the post-heater Delta T. Post-heater pressure defaults to the Post_Heater_Liquor_In pressure if not given.

What do you want to see?

Data Description

Equipment Properties

Data Descriptions

Data		Unit		Description
Set	Item	Type	Native	Description
Equipment Properties	Dome Pressure	Pressure	psia	Pressure of Liquor_Out and Steam_Out streams. If given with Area the Heat Transfer Coefficient is calculated.
	Heat Transfer Coefficient	Heat Trans Coef	BTU/hr/F/ft2	If given with Area the Dome Pressure is calculated.
	Area	Area	ft2	Heat transfer Area.
	Energy Efficiency	Fraction or Percent	Fraction	Fraction of available energy transferred to the liquor.
Post Heater	Heat Transfer Coefficient	Heat Trans Coef	BTU/hr/F/ft2	If given Area must also be given.
	Area	Area	ft2	If given Heat Transfer Coefficient must also be given.
	Delta T	Temperature Change	Delta F	Change in temperature from Post_Heater_Liquor_In to Post_Heater_Liquor_Out.
	Pressure	Pressure	psia	Post heater pressure. Defaults to Post_Heater_Liquor_In pressure.
Calculated Properties	Dome Pressure	Pressure	psia
	Heat Available for Transfer	Energy Flow	BTU/hr	This is the heat input to the evaporator body, SI * Hstm
	Evap Heat Transfer Coef	Heat Trans Coef	BTU/hr/F/ft2
	Evap Delta T	Temperature Change	Delta F	Condensate_Out temperature minus Liquor_Out temperature.
	Evap Heat Transferred	Energy Flow	BTU/hr
	BPR	Temperature	F
	Post Heater Heat Trans Coef	Heat Trans Coef	BTU/hr/F/ft2
	PH LM Delta T	Temperature Change	Delta F

Top of Page

Equipment Properties

Top of Page

Example of using equipment

Top of Page

Method&Equations

The Steam_In stream and the Condensate_In stream (if supplied) supply the energy for evaporation and post heater section.
If the Heat Transfer Coefficient and heat transfer Area are given the Dome Pressure is calculated by first calculating the saturation temperature and then calculating the corresponding saturation pressure. If the Dome Pressure is given the saturation temperature will be calculated. The energy necessary to heat the liquor to the saturation temperature is used in evaporation section; the remaining energy is used in post heater section.

Top of Page

Warnings

Being a composite item – each component may call its warnings.

Top of Page

Errors

Being a composite item – each component may call its errors.