Precision Platinum Boiling Wire Test Chamber
Pyrex glass cell housing 0.25 mm diameter platinum wire (length 100 mm) submerged in saturated water.
Chemical & Process Engineering / Pool Boiling Heat Transfer
FREE TO EXPLORELABORATORY 15 · CHEMICAL & PROCESS ENGINEERING
Pool Boiling Heat Transfer & Nukiyama Nucleate Boiling Curve Calibration
Map the pool boiling curve of saturated water over an electrically heated horizontal platinum wire, characterize the nucleate boiling regime, and determine the Rohsenow nucleate boiling parameter S relating heat flux to excess temperature. Explore interactive transport phenomena, unit operations simulation, and chemical engineering telemetry.
TRANSPORT PHENOMENA · UNIT OPERATIONS · PROCESS CONTROL · REACTION ENGINEERING
Your virtual chemical and process engineering laboratory.
CUBE ROOT HEAT FLUX (Q'')^(1/3)—
PROCESS & PILOT PLANT TELEMETRY
Ready to sample with Excess Temp ΔT_e = 15.0 K.
Adjust Excess Temp ΔT_e, then execute chemical process trial.
Chemical and process engineering telemetry is evaluated rigorously using 64-bit IEEE 754 precision. Residuals reflect ordinary least-squares regression across successive observations. Continuous data structures support high-fidelity transport phenomena and unit operations modeling.
Process engineering assumptions and boundary condition limits
The transport and thermodynamic models apply within the specified calibrated operating window (5.0 to 30.0 K). Evaluated using a 0.25 mm diameter platinum wire submerged in saturated water at 100.0 °C (P = 1.013 bar). Linear regression models (q'')^(1/3) versus ΔT_e to extract Rohsenow slope S = 2.4500 (kW/m^2)^1/3/K.
Process apparatus & industrial sensors.
Four-Terminal Kelvin Resistance Bridge
Uses platinum wire as both heating element and resistance thermometer to measure T_w with 0.05 K accuracy.
Regulated Programmable DC Power Supply
Supplies stable current from 0 to 30 A with fast electronic over-temperature burnout trip.
Reflux Vapor Condenser & Pressure Relief
Condenses boiled steam back into the pool to maintain constant liquid level and 1.013 bar pressure.
High-Speed Digital Video Microscope
Captures bubble nucleation site density, bubble departure diameter, and detachment frequency.
Immersion Auxiliary Heating Mantle
Maintains pool bulk water at exact saturation temperature T_sat = 100.0 ± 0.1 °C.
FOLLOW THE METHOD
A reason behind every step.
Map the pool boiling curve of saturated water over an electrically heated horizontal platinum wire, characterize the nucleate boiling regime, and determine the Rohsenow nucleate boiling parameter S relating heat flux to excess temperature. Standardized parameter settings: 5.0, 10.0, 15.0, 20.0, 25.0, 30.0 K.
01
Pool Deaeration & Saturation Boiling
Boil the water pool vigorously for 30 minutes with the auxiliary heater to de-aerate dissolved gases; confirm bulk water temperature is stable at 100.0 °C.
02
Wire Resistance Calibration
Measure cold resistance of the platinum wire at 100.0 °C under negligible current (< 10 mA) to establish the baseline resistance datum R_sat.
03
Initial Low Heat Flux Initiation
Increase DC power supply until wire surface excess temperature reaches ΔT_e = 5.0 K (T_w = 105.0 °C); observe isolated bubble nucleation sites.
04
Voltage, Current & Heat Flux Logging
Record voltage V and current I across wire voltage taps; calculate wire electrical resistance to find T_w, and compute heat flux q'' = V·I / (π D L).
05
Nucleate Boiling Step Progression
Increment current to advance excess temperature through 10.0, 15.0, 20.0, 25.0, and 30.0 K, logging steady-state electrical power and bubble dynamics at each plateau.
06
Rohsenow Cubic Regression Analysis
Calculate (q'')^(1/3) for each run, plot (q'')^(1/3) versus ΔT_e, and extract the slope S to evaluate the Rohsenow nucleate parameter.
YOUR NOTEBOOK · 0 OBSERVATIONS
Turn measurements into chemical process engineering insight.
Points are your recorded observations. The solid regression line validates Pool Boiling Heat Transfer mathematical scaling.
LINEAR REGRESSION FIT · y = mx + b
(q'')^(1/3) = S · ΔT_e = 2.4500 · ΔT_e
| # | Excess Temperature ΔT_e (K) | Cube Root Heat Flux (q'')^(1/3) ((kW/m^2)^1/3) | Excess temperature ΔT_e = T_w - T_sat (K) | Cube root of heat flux (q'')^(1/3) ((kW/m^2)^1/3) | Remove |
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Calculate it yourself.
CHECK YOUR UNDERSTANDING
Explain what the process engineering metrics mean.
In the nucleate pool boiling regime, heat flux q'' scales with excess temperature ΔT_e approximately as:
The peak point on the Nukiyama pool boiling curve separating nucleate boiling from transition boiling is called:
The Leidenfrost point on the boiling curve corresponds to:
Excess temperature ΔT_e in boiling heat transfer is defined as:
THEORY AND UNIT OPERATIONS CONTEXT
Process engineering background & physical principles.
Boiling heat transfer constitutes one of the most effective thermal transport mechanisms in chemical process engineering, delivering heat transfer coefficients orders of magnitude higher than single-phase convection. In steam boilers, thermosiphon reboilers, evaporators, and nuclear reactor cooling cores, boiling occurs when a solid heating surface is maintained at a temperature T_w above the liquid saturation temperature T_sat; the temperature difference ΔT_e = T_w - T_sat is termed the excess temperature. In 1934, Shiro Nukiyama experimentally mapped the complete pool boiling curve of water using an electrically heated platinum wire, identifying four distinct regimes: natural convection, nucleate boiling, transition boiling, and film boiling. In the nucleate boiling regime (typically 5 K < ΔT_e < 30 K for water at atmospheric pressure), vapor bubbles nucleate at microscopic surface cavities, grow, and detach into the liquid pool. Bubble departure pumps cold liquid directly to the wall while latent heat absorption drives immense heat flux. Warren M. Rohsenow (1952) established the foundational correlation for nucleate pool boiling: q'' = μ_l · h_fg · [g (ρ_l - ρ_v) / σ]^0.5 · [c_p,l · ΔT_e / (C_sf · h_fg · Pr_l^n)]^3. Crucially, Rohsenow's relation reveals that nucleate boiling heat flux q'' scales with the cube of excess temperature: q'' ∝ (ΔT_e)^3, meaning (q'')^(1/3) scales linearly with ΔT_e. In this laboratory investigation, an instrumented platinum wire boiling cell is operated across excess temperatures from 5.0 to 30.0 K to measure heat flux q'', verify Rohsenow cubic scaling, and determine the nucleate boiling parameter S.
(q'')^(1/3) = S · ΔT_e = 2.4500 · ΔT_e
Evaluated using a 0.25 mm diameter platinum wire submerged in saturated water at 100.0 °C (P = 1.013 bar). Linear regression models (q'')^(1/3) versus ΔT_e to extract Rohsenow slope S = 2.4500 (kW/m^2)^1/3/K.