Falling Film Evaporator Tubes | Uniform Film Distribution Enhanced Tubes

Falling film evaporator tubes are specially designed for falling film evaporation systems. In a falling film evaporator, liquid is uniformly distributed onto the inner or outer surface of the tube bundle through a distribution device at the top, forming a thin film that flows downward while being heated and evaporated.

Kenergy's falling film evaporator tubes feature optimized surface structures that ensure uniform liquid film coverage, preventing dry spots and fouling while maximizing heat transfer area and fluid disturbance. These tubes are widely used in central air conditioning falling film chillers, seawater desalination plants, food concentration equipment, and chemical evaporation systems. Multi-material options are available to suit different working fluids and operating conditions.

Core Advantages

Uniform Film Distribution Design

Specially engineered surface geometry promotes even liquid film spread across the tube surface, preventing dry spots, localized overheating, and scaling.

High Film-Side Heat Transfer

Enhanced surface structures increase film-side turbulence and effective heat transfer area, delivering superior overall heat transfer coefficients vs. conventional tubes.

Anti-Fouling Performance

Optimized surface finish reduces scale adhesion and fouling buildup, extending operational cycles between cleaning and reducing maintenance costs.

Multi-Material Availability

Available in copper, copper-nickel, stainless steel (304/316L), and titanium to suit different fluid chemistries, temperature ranges, and corrosion resistance requirements.

Technical Parameters

Available outer diameters, wall thicknesses, surface structures, and material options. Custom specifications available upon request.

Outer Diameter (mm)	Wall Thickness (mm)	Tube Length (m)	Surface Structure	Working Fluid	Material Options
19.05	0.80–1.20	3–12	Smooth / Low-Fin / Film-Forming	Water / Refrigerant / Solutions	TP2, CuNi10Fe1Mn, 304/316L, Ti
25.40	0.90–1.50	3–12	Smooth / Low-Fin / Film-Forming	Water / Refrigerant / Solutions	TP2, CuNi10Fe1Mn, 304/316L, Ti
31.80	1.00–1.80	3–10	Smooth / Low-Fin / Film-Forming	Water / Seawater / Solutions	TP2, CuNi10Fe1Mn, 304/316L, Ti
50.80	1.20–2.00	3&ndash.8	Smooth / Low-Fin / Film-Forming	Seawater / Solutions / Chemicals	CuNi10Fe1Mn, 304/316L, Ti

Typical Applications

Central HVAC Falling Film Chillers

Falling film evaporators for large commercial and industrial centrifugal chiller systems in office buildings, hotels, and hospitals.

Multi-Effect Distillation Desalination

Heat transfer tubes for MED (multi-effect distillation) seawater desalination plants producing fresh water from seawater.

Food Concentration Equipment

Evaporator tubes for concentrating fruit juices, dairy products, syrups, and other food liquids in the food processing industry.

Chemical Evaporation & Crystallization

Falling film evaporators for chemical solutions, brine concentration, and crystallization processes in the chemical industry.

Frequently Asked Questions

Q: What is the difference between falling film evaporator tubes and flooded evaporator tubes?

In a flooded evaporator, tubes are fully submerged in liquid refrigerant or coolant, with boiling occurring directly on the tube surface. In a falling film evaporator, liquid is distributed as a thin film flowing down the tube surface, with evaporation occurring from the film. This key difference drives distinct tube surface requirements: flooded tubes need enhanced boiling surfaces (porous, finned) to promote nucleate boiling, while falling film tubes need surfaces that promote uniform film spreading and maintain film stability. Falling film designs also typically require less refrigerant charge and offer better temperature approach.

Q: How do you ensure uniform liquid film distribution across the tube bundle?

Uniform film distribution is achieved through a combination of proper liquid distribution system design and tube surface optimization. Our tubes feature surface structures that promote rapid and even liquid spreading across the tube circumference. On the system level, proper inlet distributor design, tube pitch selection, and liquid load per tube are critical. Kenergy provides both tube products and distribution design recommendations to ensure optimal wetting. We also offer custom surface patterning for enhanced film-forming characteristics in challenging applications.

Q: How do you clean fouled falling film tubes?

Cleaning methods depend on the type of fouling. For soft scale and organic fouling, chemical cleaning with appropriate detergents or mild acids is effective. For hard mineral scale, controlled acid cleaning with inhibitors is recommended. For tubes with smooth or low-fin surfaces, mechanical cleaning with soft brushes or high-pressure water jets is also possible. Our anti-fouling surface treatment significantly reduces the frequency of cleaning. We recommend establishing a regular inspection and cleaning schedule based on your specific water chemistry and operating conditions.

Q: Can falling film tubes be used for seawater desalination? What material do you recommend?

Yes, falling film evaporator tubes are widely used in multi-effect distillation (MED) and mechanical vapor compression (MVC) desalination plants. For seawater desalination, we recommend CuNi10Fe1Mn (90/10 copper-nickel) for its excellent corrosion resistance in seawater environments. For higher temperature stages or more aggressive conditions, 316L stainless steel or titanium (Grade 2) are also available. The tube surface structure can be optimized for enhanced wetting and heat transfer with seawater. Kenergy has extensive experience supplying tubes for desalination projects worldwide.

Falling Film Evaporator Tubes — Uniform Film Distribution Enhanced Tubes