Engine Nacelle Halon Replacement

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Engine Nacelle Halon Replacement
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PRESENTATION CONTENTS

• OVERVIEW OF PENDING ANALYSIS FOR THE
  OVER-PRESSURE BEHAVIOR IN THE NACELLE FIRE
  SIMULATOR
• BRIEF DESCRIPTION OF PROBLEM
• DESCRIPTIONS OF MODIFICATIONS TO TEST FIXTURE
• NEW TELEMETRY
• DUCT INTERFACE BOX
• TEST PLAN
• INITIAL OBSERVATIONS
• GENERIC STATUS
• TESTING REMAINING
• TABLE OF CALCULATED EQUIVALENT CONCENTRATIONS

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OVER-PRESSURE ANALYSIS

• PENDING OVER-PRESSURE ANALYSIS

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OVER-PRESSURE ANALYSIS - OVERVIEW

• DURING TESTING WITH 2-BTP HFC-125 ANOMOLOUS
  BEHAVIOR WAS NOTED IN THE TEST FIXTURE
• BEHAVIOR CHARACTERIZED AS AN OVER-PRESSURE AT AN
  ATMOSPHERIC GAP IN THE FIXTURE
• WORST-CASE EXAMPLE RESULTED IN FIREBALL AUDIBLE
  SIGNATURE
• NO TELEMETRY ORIGINALLY LOCATED IN REGION OF
  INTEREST
• TEST FIXTURE HAS BEEN MODIFIED TO ALLOW
  COLLECTION OF PERTINENT DATA
• DATA TO BE COLLECTED AND SCRUTINIZED TO ASSESS
  MAGNITUDE AND ATTEMPT AN UNDERSTANDING

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OVER-PRESSURE ANALYSIS, PERTINENT TEST FIXTURE
GEOMETRY
AIR FLOW
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OVER-PRESSURE ANALYSIS, PERTINENT TEST FIXTURE
GEOMETRY
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OVER-PRESSURE ANALYSIS FIXTURE MODIFICATIONS

• ADDED 4 THERMOCOUPLES IN RED DUCT
• ALL ALONG 1200
• STARTED 2 FEET IN FROM INLET, PLACED EVERY 2 FEET
• BEADS ARE 8 INCHES OFF WALL
• ADDED 2 STATIC PRESSURE MEASUREMENT LOCATIONS
• 0-5 H2O PSID (REFERENCE TO TEST BAY)
• 1 POINT IN TEST SECTION, 0300, STA 522
• 1 POINT IN RED DUCT SECTION, 0430, 21 INCHES IN
  FROM INLET
• USING STATIC PORTS OFF 1/8OD PITOT-STATIC TUBES
  INSERTED INTO FLOW FIELD

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OVER-PRESSURE ANALYSIS FIXTURE MODIFICATIONS

• ADDED 4 OPTO-ELECTRONIC DEVICES TO DETECT FLAME
  PROPRAGATION THROUGH TEST FIXTURE
• PHOTODIODE PHOTOCONDUCTIVE CIRCUITS
• SENSOR VALUES
• ? 0 VDC, DARK/NO FIRE
• ? 6.1 VDC, SATURATES WHEN VIEWING FLAMES OF TEST
  FIRE
• 1 VIEWS TUBE ARRAY IN FIRE ZONE
• REMAINING 3 LOOK AT 1200
• ENTRANCE TO EXHAUST NOZZLE
• EXIT OF EXHAUST NOZZLE
• RED DUCT
• A BOX IS BEING FABRICATED WHICH WILL CLOSE OUT
  THE DUCT INTERFACE COMPLETELY

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OVER-PRESSURE ANALYSIS, TELEMETRY LOCATIONS
STA 502
STA 527
STA 551
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OVER-PRESSURE ANALYSIS TEST PLAN

• PURPOSE
• TO CAPTURE THE ENVIRONMENT OF THE OVER-PRESSURE
  PRODUCED BY HFC-125
• TO CAPTURE THE ENVIRONMENT AS PRODUCED BY HALON
  1301
• CHARACTERIZE THE MAGNITUDE OF THE ENVIRONMENT
• ATTEMPT TO TO UNDERSTAND THE PHENOMENA
• PLAN
• FIRE TEST WITH HFC-125 IN CONFIGURATIONS WHERE
  OVER-PRESSURES WERE PREVIOUSLY OBSERVED
• FIRE TEST WITH HALON 1301 IN THE SAME CONDITION
• RUN EACH AGENT WITH WITHOUT THE DUCT INTERFACE
  BLOCKED OUT
• MULTIPLE OVER-PRESSURES WILL BE CAPTURED
• MULTIPLE HALON 1301 FIRE TESTS PLANNED TO CAPTURE
  BEHAVIOR
• EXACT TEST COUNT TBD

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OVER-PRESSURE ANALYSIS INITIAL OBSERVATIONS

• THE FOLLOWING GRAPHS ILLUSTRATE SOME OBSERVATIONS
• BASED ON 1.0 lbm/s 260F VENTILATION, 0.25 GPM
  OIL SPRAY FIRE, HFC-125 AT equivalence
• THE FOLLOWING BEHAVIORS WERE OBSERVED
• THIS TEST VISUALLY PRODUCED A MINOR
  OVER-PRESSURE
• GRAPH OF FIRE IGNITION, INITIAL VS. REIGNITION AT
  COMPLETION OF REIGNITION TIME DELAY (RTD)
• FLAME FRONT PROPAGATION IS QUICKER DURING INITIAL
  IGNITION
• FIRE GROWTH IS QUICKER DURING REIGNITION
• STATIC PRESSURE PULSE IS LARGER FOR REIGNITION
• STATIC PRESSURE PULSE IS FRACTIONAL INCH
  MAGNITUDE
• GRAPH OF THE COMPLETE REIGNITION TIME DELAY
• FLAME EXTINCTION AT RTD ONSET DOES NOT PROGRESS
  LOGICALLY
• FLAME REIGNITION AFTER RTD PROGRESSES LOGICALLY
• STATIC PRESSURE HAS GREATER PULSE DURING FIRE
  REIGNITION THAN DURING AGENT DISCHARGE
• GRAPH OF OVERALL TEMPERATURE BEHAVIOR INDICATES
  NOTHING UNUSUAL

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OVER-PRESSURE ANALYSIS INITIAL OBSERVATIONS,
FIRE IGNITION
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OVER-PRESSURE ANALYSIS INITIAL OBSERVATIONS,
COMPLETE RTD
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OVER-PRESSURE ANALYSIS INITIAL OBSERVATIONS
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OVER-PRESSURE ANALYSIS INITIAL OBSERVATIONS

• THERE ARE NO CONCLUSIONS TAKEN FROM THIS ONE
  TEST, JUST OBSERVATIONS
• MORE TESTING TO BE COMPLETED PRIOR TO ANALYSIS

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CONCLUSION

• SUMMARY/STATUS

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CONCLUSORY STATEMENTS

• TESTING REGARDING CHARACTERIZING OVER-PRESSURE
  BEHAVIOR REQUIRES COMPLETION
• REMAINING CF3I EQUIVALENCE ITERATIONS WILL FOLLOW
• POOL FIRE WORK
• SPRAY FIRE WORK
• COLD AGENT TESTING

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RESULTS TO DATE - TABULAR