Transformer Water Spray Protection

Main transformer water-spray (GB50219-95): protection area, nozzle selection q=K(10P)^0.5 and actual spray-intensity verification.

1. Basic design parameters

Pit spray intensity W1 (L/min·m²)

Body spray intensity W2 (L/min·m²)

Oil pit length (m)

Oil pit width (m)

Body length (m)

Body width (m)

Body height (m)

Oil pillow diameter (m)

Oil pillow length (m)

2. Protection areas (m²)

S1 · 2·L·H

—

m²

S2 · 2·W·H

—

m²

S3 · L·W

—

m²

S4 · pillow

—

m²

S5 · pit

—

m²

S6 · body total

—

m²

S7 · pit−S3

—

m²

3. Nozzle selection (q = K·√(10P))

Pressure P (MPa)

1. Oil pillow K

2. Body top K

3. Body long side K

4. Body short side K

5. Oil pit K

1. Nozzle flow q

—

L/min

1. Nozzles n

—

pcs

2. Nozzle flow q

—

L/min

2. Nozzles n

—

pcs

3. Nozzle flow q

—

L/min

3. Nozzles n

—

pcs

4. Nozzle flow q

—

L/min

4. Nozzles n

—

pcs

5. Nozzle flow q

—

L/min

5. Nozzles n

—

pcs

4. Spray intensity verification (Wj = Q/S)

1. Oil pillow Q (L/min)

2. Body top Q (L/min)

3. Body long Q (L/min)

4. Body short Q (L/min)

5. Oil pit Q (L/min)

1. Oil pillow · req ≥ W2

—

L/min·m²

2. Body top · req ≥ W2

—

L/min·m²

3. Body long · req ≥ W2

—

L/min·m²

4. Body short · req ≥ W2

—

L/min·m²

5. Oil pit · req ≥ W1

—

L/min·m²

System flow Qj (L/s)

Design flow Qs = 1.05·Qj

5. Simplified pipeline hydraulic check

Node pressure C = C0 + Σh of the previous segment; nozzle flow F = E·(10C/100)^0.5; segment flow G = previous G + F; velocity V = 400·G/(6·π·I²); gradient i = 0.00107·V²/(I/1000)^1.3; loss = 1.2·D·i; running total N = 1.2·D·i + prev N + Δh.

Initial node pressure C0 (m)

Node	Segment	Node pressure C	Segment length D (m)	Nozzle coeff E	Nozzle flow F	Segment flow G	Design dia H (mm)	Calc dia I (mm)	Velocity V (m/s)	Gradient i	Loss (m)	Δh (m)	Σh (m)

Areas: S1 = 2·L·H, S2 = 2·W·H, S3 = L·W, S4 = π·d·l/2 + π·d²/2, S5 = pit length·width, S6 = S1+S2+S3+S4, S7 = S5−S3. Nozzle q = K·(10P)^0.5 (L/min); quantity n = S·W/q; verified Wj = Q/S. Covers GB50219-95 requirements.