Видео

How was the cbush stiffness calculated ? What spring stiffnesses were used , translating and rotation direction?

Thanks for sharing. Did you manually put in the 0.7 rotation? If so, how did you come up with this value?

Please share the Nastran SOL200 Web App, from where we can download the pdf's and example BDF files.Thanks

Hi, thanks for the video. Can you show how to export Stiffness Matrix from MSC Nastran to HDF5 file? What is the card entry for the same?

Hello your videos are great. Thank you! Could you please make a video in PATRAN of how to model a bolted joint using (1) beam elements with RBE2s and (2) CBUSH and then compare the results of the bolt forces (Fx, Fy, Fz, Mx, My, Mz with coordinate definition) for both methods?

Quite informative video!

This video was the second take on Nastran coordinate systems. For those interested in a slightly different explanation of Nastran coordinate systems, the first take is available at this link: ruclips.net/video/FIJI3YH3DKY/видео.html

Link the mentioned Python script: mscnastrannovice.blogspot.com/2024/03/how-to-export-nastran-cbush-element.html

How to do this directly in patran?

Thank you so much for these tutorials, incredibly informative and helpful channel on the subject of optimization.

Hello, I am from 5 years in the future and still waiting for you to post said link in the description above!

Very helpful video. Thank you in South Korea.

Thank you for sharing your knowledge in this video Christian. It has helped me better understand how topological optimization works😀

# Below is Python code that does the same procedure but faster import h5py import numpy import json class NumpyEncoder(json.JSONEncoder): def default(self, obj): if isinstance(obj, numpy.floating): return numpy.float64(obj).item() return json.JSONEncoder.default(self, obj) # Comments: # A list of datasets is available in: # 1. web.mscsoftware.com/doc/nastran/2018/release/DataType.html # 2. The nastran documentation directory, e.g. /msc/MSC_Nastran_Documentation/2021.4/doc/relnotes/v20214/DataType_v20214.html def write_dataset_to_csv_file(path_of_h5_file, dataset_name, name_of_csv_file): file = h5py.File(path_of_h5_file, 'r') # Recover the DOMAINS dataset and index it # The DOMAINS dataset contains information about the SUBCASE, TIME_FREQ_EIGR, etc. dataset_domains = file['/NASTRAN/RESULT/DOMAINS'] dataset_original_domains_in_list_form = dataset_domains[...].tolist() dataset_domains_index = ['dummy_element_a', 'dummy_element_b'] for line in dataset_original_domains_in_list_form: dataset_domains_index.insert(line[0], line) # Recover the dataset of interest dataset1 = file[dataset_name] dataset_original = dataset1[...].tolist() # Column names # Take the column names from the H5 file (type: tuple), convert to a python list (type: list), and # generate a string to add to the CSV file column_names_domains = dataset_domains.dtype.names column_names_domains = list(column_names_domains) column_names = dataset1.dtype.names column_names = list(column_names) name_of_last_column = column_names[len(column_names) - 1] column_names = ', '.join(column_names) column_names = column_names + ', ' + ', '.join(column_names_domains) # Determine if there are SUBCASEs (DOMAINS) to add attach_domains = False if name_of_last_column == 'DOMAIN_ID': attach_domains = True # Begin adding the data to the CSV file text_file = open(name_of_csv_file, 'w', encoding='utf8', errors='replace') text_file.write(column_names + ' ') for line in dataset_original: # The .tolist() is suppose to take any number that is of type 'numpy.float64' and convert it to a python type # 'float.' When reading dsoug7.H5 or dsoug10.h5, some issues were encountered. # After some research, the solution was to build a custom encoder such that if a type 'numpy.float64' sneaks in # the custom encoder, NumpyEncoder will manually convert it to a Python float type. outgoing_string = json.dumps(line, cls=NumpyEncoder) # If this dataset has corresponding DOMAINs (SUBCASE, TIME_FREQ_EIGR, etc.), then associate # the information if attach_domains is True: domain_id = line[len(line) - 1] # The DOMAIN_ID is in the last column of the dataset of interest line_in_domains = dataset_domains_index[domain_id] # Recover the corresponding DOMAIN from the indexed list dataset_domains_index outgoing_string_domain = json.dumps(line_in_domains, cls=NumpyEncoder) # Convert each number outgoing_string = outgoing_string + ',' + outgoing_string_domain # Create a line to add to the CSV file # Replace any brackets outgoing_string = str.replace(outgoing_string, ']', '') outgoing_string = str.replace(outgoing_string, '[', '') # Add a new line character to force a separate line outgoing_string = outgoing_string + ' ' # Add the line to the CSV file text_file.write(outgoing_string) # Close the file text_file.close() if __name__ == '__main__': write_dataset_to_csv_file('model.h5', '/NASTRAN/RESULT/ELEMENTAL/STRESS/ROD', 'file_1.csv') write_dataset_to_csv_file('model.h5', '/NASTRAN/RESULT/NODAL/DISPLACEMENT', 'file_2.csv')

Auto Model's Units are on inches AND with scale factor of 39.37 ????? THIRTY NINE POINT THIRTY SEVEN..........They can't be serious, what the actually (d)uck bro. Ultra modified McDonald's - Imperial system and kolokithia tubana as we say in my village.

In matlab

Good video and thanks for sharing knowledge, who to choose your Latin hypercube sampling ?

Did not like the video. Needs a lot of improvement.

What about defining the response for multiple nodes?

help me please

why the result of the first natural frequency equal 0

excuse me sir. i want to asking about msc nastran to you. because i have a final project in my university. help me please. thanks

thank you very much it was very helpful, thanks chris

Hello there ! I have a university project on nastran and i would be needing a mechanical automobile part such as a brake or spark plus etc, would you be kind enough to send me a file of a part on email that i can study, it would be really nice of you 🙏🏻

You have not posted the link for HDF5 Viewer

Is there any charge for student project??

hello, u contraire to the statement above, there is no link to the viewer program in your descripion above !

at minute 24:48 why are the "Include in Objective" boxes not checked for a4 a5 and a6?

Hello, nice and rare tutorial! Thank you!

Awesome brother keep posting

Hi, how to export deformed surface from Nastran output, is there a grid points which can used in bicubic mesh surafce?

I see in your webinar that you have used some web app to generate the Nastran cards. Can't we do the same via Patran?

Hello How can i access to the webbapp ? Great website by the way ! So much informations on Sol200 ! Thanks in advance Clément

hi wht is the meaning of time-5 ? and why need param card

I appreciate your work! Keep it on and have a lot success you deserve it!

very informative sir.. thankyou

Very informative!

To select text vertically in Notepad ++, hold down the ALT key when selecting text.

Free Nastran SOL 200 / Optimization live training. Email me for info: christian@ the-engineering-lab.com .

Free Nastran SOL 200 / Optimization live training. Email me for info: christian@ the-engineering-lab.com .