I have now fully automated my A_Harman index, effective VII content, and base-oil viscosity calculator by building in the ASTM D341 viscosity - temperature relation (Walther formula) into the spreadsheet.
If you want to calculate these values for an oil, you can either (a) make a copy of the Google sheet or (b) download it as an Excel file from the File menu so that you can edit and work on it:
>> Estimated base-oil viscosity @ 150 °C (BO DV150) and VII content of selected oils <<
Input values needed (gold columns):
![[Linked Image from lh3.googleusercontent.com]](https://lh3.googleusercontent.com/a-Jho7iL-7Afd4lg9488FUZydzLgu9a69q6I86J5nz2vzQOvy_dH-xD0ZTaSqTNph0hyWXrTFJHE0HQCh-P3m5yVUsoraNqRJrihELL2xGnfFve0pXqoDuzh7iwXsiEMUkFxnca5lXAwQup_n474vi_9IxZ2FHCpTieqLu5mdzU0KYTAyyJeHWgEJYFEIzA7m6XqhA8EfiTtKhiMb_cYSLIJ1hryxIiG_GfSkpf5su-I2bVzxnLV9EIjEvkkWCdbICeb8VR2_t5ddzIUCYp74ocVbtdtVCBi8F6waR8xMk8AxwYXury1_tHV7z8Z2uhC7zl7hVQcRoWAPf2NK7SdcrzioG9NTAGsTZbPswHNReF2MPu72ip6SVsEDIJ3U2Zfm9PSjLMUT1qsp1c3FcVKqHb_9bLId4PlvBVU_rOTM3RpBsydJbG3IpV_ussMa-dm6fxkMTXtuA3K6kbFzXi4p9ScFCgKzpkIID_wKEW2f47e16699vQaUlQOz7RcNnq9zuwy1G6UxAXyMhLCWkWwq7ENq2vJVD-Yp-N-mhN8nbvJfdL0ZZmN3Zar_jiuBtTigtmEVi63e7qe2TS_XmEMyPMIhAFwwMxaAMnWMxh3IOD5YeTcuyfsUcWiLORHfy-1m15gMa4CsVtkSlLIh_-5fXx7Yo-URfNkvwK396doSh--CDxN58M3_Vnw9u_Jew=w851-h2160-no?.png)
- oil name (info only)
- density at 60 °F (15.6 °C) (g/cm³)
- KV40 (cSt)
- KV100 (cSt)
- VI (info only)
- HTHS (cP) (high-temperature, high-shear viscosity)
- A_Harman index: a measure of the effective viscosity-index improver (VII) content through the temporary shear of the oil
- VII content: effective VII content (measured by the temporary shear, not the actual solid or oil-solvent-dissolved VII content) directly given by the A_Harman index
- BO DV150 (HTFS) (cP): base-oil (plus the additive package) viscosity at 150 °C excluding the VII -- high-temperature, full-shear viscosity -- directly given by the A_Harman index and HTHS
![[Linked Image from lh3.googleusercontent.com]](https://lh3.googleusercontent.com/a-Jho7iL-7Afd4lg9488FUZydzLgu9a69q6I86J5nz2vzQOvy_dH-xD0ZTaSqTNph0hyWXrTFJHE0HQCh-P3m5yVUsoraNqRJrihELL2xGnfFve0pXqoDuzh7iwXsiEMUkFxnca5lXAwQup_n474vi_9IxZ2FHCpTieqLu5mdzU0KYTAyyJeHWgEJYFEIzA7m6XqhA8EfiTtKhiMb_cYSLIJ1hryxIiG_GfSkpf5su-I2bVzxnLV9EIjEvkkWCdbICeb8VR2_t5ddzIUCYp74ocVbtdtVCBi8F6waR8xMk8AxwYXury1_tHV7z8Z2uhC7zl7hVQcRoWAPf2NK7SdcrzioG9NTAGsTZbPswHNReF2MPu72ip6SVsEDIJ3U2Zfm9PSjLMUT1qsp1c3FcVKqHb_9bLId4PlvBVU_rOTM3RpBsydJbG3IpV_ussMa-dm6fxkMTXtuA3K6kbFzXi4p9ScFCgKzpkIID_wKEW2f47e16699vQaUlQOz7RcNnq9zuwy1G6UxAXyMhLCWkWwq7ENq2vJVD-Yp-N-mhN8nbvJfdL0ZZmN3Zar_jiuBtTigtmEVi63e7qe2TS_XmEMyPMIhAFwwMxaAMnWMxh3IOD5YeTcuyfsUcWiLORHfy-1m15gMa4CsVtkSlLIh_-5fXx7Yo-URfNkvwK396doSh--CDxN58M3_Vnw9u_Jew=w851-h2160-no?.png)