My flyback converter not working

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Hi

my power supply input 195-265 V AC Single 230 VAC input

100 W 19 V output

I see 34-38 V at output and ripple is almost +- 2 V in no load. Also  when i load the power supply with 15 ohm, there will be no voltage (0 V). What is the wrong?

 

Also i want some other questions. My design procudure: 

Firstly I design my power supply  with AN-16. After that i try transformer with PIXls designer and i have manufacturer do transformer. After i took my tranformer, i set up the circuit with PI expert  and see some faults aboout transformer:

1-  There is no limit for air gap on AN16 and PIXls designer. But PI expert  says air gap to high.  Is there important? 

2-  What is the meanig and importance number of primary layer L? 

3-  Diode conduction time at AN16 is different from PI expert and it affect the number of primary turns. Which one is true AN16 or PI expert?