🔄 Scraped Surface Heat Exchanger Sizer (SSHE)

Size and design Scraped Surface Heat Exchangers (SSHE Votator / Contherm): Trommelen heat transfer model, rotational Reynolds number, product outlet temp, and shaft motor power.

⚡ Fortran 90 Engine Double Precision (IEEE 754) ✓ ISO / ASME Validated

Heat Exchangers

📊 Solver Telemetry ● ACTIVE

👁️ Views 18

⚡ Solves 17

💾 Downloads 369 📦 Fortran Code 4.1 KB

📅 Released Jun 2026

⏱️ Latency < 1 ms

🔄 SSHE Rotating Scraper Blades & Boundary Layer Scraping

Real-time visual simulation: High-speed scraper blades wiping viscous boundary layer against the cooling jacket

📝 Configuration & Presets

🍦 Ice Cream Slush Freezer 🍅 Tomato Paste SSHE Cooler 🧈 Margarine Fat Crystallizer 🍲 Starch Gelatin Cooker

🥫 Viscous Product Medium

Product Type:

Product Mass Flow ṁ [kg/s]:

Product Inlet Temp T_in [°C]:

❄️ Jacket Utility & Scraper Mechanics

Jacket Temperature T_jack [°C]:

Scraper Rotor Speed N [rpm]:

Number of Scraper Blades N_b:

📐 SSHE Cylinder Dimensions

Cylinder Inner Diameter D_i [mm]:

Cylinder Active Length L [m]:

Trommelen & Beek SSHE Formulation:
• Rotational Reynolds: Re_r = ρ · (N/60) · D_i² / μ
• Scraped Nusselt: Nu = 0.16 · Re_r^0.50 · Pr^0.33 · N_b^0.33
• Scraped Film Coeff: h_p = Nu · k / D_i [W/(m²·K)]
• Total Heat Duty: Q̇ = ṁ · c_p · ΔT + ṁ · Δh_latent [kW].

📊 SSHE Performance Results

📊 Output Summary
💾 Fortran Source

Transferred Thermal Duty (Q̇)

5.4 kW

Overall U: 126 W/(m²·K) | Scraped Film h_p: 137 W/(m²·K)

2 Blades @ 220 RPM

Product Outlet Temperature (T_out) 27.4 °C Inlet = 25 °C | Jacket = 120 °C

Scraper Motor Power Demand 0.46 kW 0.62 HP Mechanical Drive

Rotational Reynolds (Re_r) 85 Boundary layer renewal

Heat Transfer Area (A) 0.45 m² L = 1.2 m, D = 120 mm

📈 Heat Duty Q̇ (kW) vs Scraper Rotor Speed N (rpm)

📊 Scraped Film Coeff hp [W/(m²·K)] vs Blades Count Nb

=================================================================
 THERMOFLUIDCALC — SCRAPED SURFACE HEAT EXCHANGER REPORT
=================================================================
Case Title                 : Starch Gelatinization Steam Cooker
Product Type               : Gelatin / Modified Starch (Viscous Cooking)
Product Flow & Temp        : m_dot = 0.60 kg/s, Tin = 25.0 C, Jacket = 120.0 C
SSHE Geometry & Scraper    : D = 120.0 mm, L = 1.20 m, N = 220 rpm, Blades = 2
-----------------------------------------------------------------
THERMAL HEAT DUTY (Q)      : 5.36 kW
Scraped Film Coeff (hp)    : 136.6 W/(m2.K)
Overall Heat Transfer (U)  : 126.3 W/(m2.K)
Product Outlet Temperature : 27.35 deg C
Heat Transfer Area         : 0.45 m2
Rotational Reynolds (Re_r) : 85
Scraper Drive Motor Power  : 0.46 kW (0.62 HP)
=================================================================

📘 Calculation Methodology & SSHE Standards

Continuous Boundary Layer Renewal

Spring-loaded or centrifugal scraper blades continuously scrape the heat exchange cylinder wall, preventing fouling and burning of sticky, heat-sensitive or crystallizing food and chemical products.

Trommelen & Beek Heat Transfer Model

Evaluates the unsteady heat conduction into the liquid film between successive blade passes, scaling with $\sqrt{N \cdot N_b}$.

Key Engineering Assumptions

Uniform jacket temperature (evaporating refrigerant or condensing steam).
Power law and high-shear viscous friction dissipation included in shaft load.
Applicable to ice cream slush freezers, tomato paste, margarine, peanut butter, and gelatin.

ThermoFluidCalc Engineering Report